This patch provides an enhancement to kexec/kdump. It implements the
following features:
- Backup/restore memory used by the original kernel before/after
kexec.
- Save/restore CPU state before/after kexec.
The features of this patch can be used as a general method to call program in
physical mode (paging turning off). This can be used to call BIOS code under
Linux.
kexec-tools needs to be patched to support kexec jump. The patches and
the precompiled kexec can be download from the following URL:
source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2
patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2
binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10
Usage example of calling some physical mode code and return:
1. Compile and install patched kernel with following options selected:
CONFIG_X86_32=y
CONFIG_KEXEC=y
CONFIG_PM=y
CONFIG_KEXEC_JUMP=y
2. Build patched kexec-tool or download the pre-built one.
3. Build some physical mode executable named such as "phy_mode"
4. Boot kernel compiled in step 1.
5. Load physical mode executable with /sbin/kexec. The shell command
line can be as follow:
/sbin/kexec --load-preserve-context --args-none phy_mode
6. Call physical mode executable with following shell command line:
/sbin/kexec -e
Implementation point:
To support jumping without reserving memory. One shadow backup page (source
page) is allocated for each page used by kexeced code image (destination
page). When do kexec_load, the image of kexeced code is loaded into source
pages, and before executing, the destination pages and the source pages are
swapped, so the contents of destination pages are backupped. Before jumping
to the kexeced code image and after jumping back to the original kernel, the
destination pages and the source pages are swapped too.
C ABI (calling convention) is used as communication protocol between
kernel and called code.
A flag named KEXEC_PRESERVE_CONTEXT for sys_kexec_load is added to
indicate that the loaded kernel image is used for jumping back.
Now, only the i386 architecture is supported.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 9115d13453 ("powerpc: Enable
AT_BASE_PLATFORM aux vector") broke boot on 32-bit powerpc systems; we
have to use PTRRELOC to initialize powerpc_base_platform this early in
boot.
Bug reported by Jon Smirl.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (34 commits)
powerpc: Wireup new syscalls
Move update_mmu_cache() declaration from tlbflush.h to pgtable.h
powerpc/pseries: Remove kmalloc call in handling writes to lparcfg
powerpc/pseries: Update arch vector to indicate support for CMO
ibmvfc: Add support for collaborative memory overcommit
ibmvscsi: driver enablement for CMO
ibmveth: enable driver for CMO
ibmveth: Automatically enable larger rx buffer pools for larger mtu
powerpc/pseries: Verify CMO memory entitlement updates with virtual I/O
powerpc/pseries: vio bus support for CMO
powerpc/pseries: iommu enablement for CMO
powerpc/pseries: Add CMO paging statistics
powerpc/pseries: Add collaborative memory manager
powerpc/pseries: Utilities to set firmware page state
powerpc/pseries: Enable CMO feature during platform setup
powerpc/pseries: Split retrieval of processor entitlement data into a helper routine
powerpc/pseries: Add memory entitlement capabilities to /proc/ppc64/lparcfg
powerpc/pseries: Split processor entitlement retrieval and gathering to helper routines
powerpc/pseries: Remove extraneous error reporting for hcall failures in lparcfg
powerpc: Fix compile error with binutils 2.15
...
Fixed up conflict in arch/powerpc/platforms/52xx/Kconfig manually.
Currently list of kretprobe instances are stored in kretprobe object (as
used_instances,free_instances) and in kretprobe hash table. We have one
global kretprobe lock to serialise the access to these lists. This causes
only one kretprobe handler to execute at a time. Hence affects system
performance, particularly on SMP systems and when return probe is set on
lot of functions (like on all systemcalls).
Solution proposed here gives fine-grain locks that performs better on SMP
system compared to present kretprobe implementation.
Solution:
1) Instead of having one global lock to protect kretprobe instances
present in kretprobe object and kretprobe hash table. We will have
two locks, one lock for protecting kretprobe hash table and another
lock for kretporbe object.
2) We hold lock present in kretprobe object while we modify kretprobe
instance in kretprobe object and we hold per-hash-list lock while
modifying kretprobe instances present in that hash list. To prevent
deadlock, we never grab a per-hash-list lock while holding a kretprobe
lock.
3) We can remove used_instances from struct kretprobe, as we can
track used instances of kretprobe instances using kretprobe hash
table.
Time duration for kernel compilation ("make -j 8") on a 8-way ppc64 system
with return probes set on all systemcalls looks like this.
cacheline non-cacheline Un-patched kernel
aligned patch aligned patch
===============================================================================
real 9m46.784s 9m54.412s 10m2.450s
user 40m5.715s 40m7.142s 40m4.273s
sys 2m57.754s 2m58.583s 3m17.430s
===========================================================
Time duration for kernel compilation ("make -j 8) on the same system, when
kernel is not probed.
=========================
real 9m26.389s
user 40m8.775s
sys 2m7.283s
=========================
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are only 4 valid name=value pairs for writes to
/proc/ppc64/lparcfg. Current code allocates a buffer to copy
this information in from the user. Since the longest name=value
pair will easily fit into a buffer of 64 characters, simply
put the buffer on the stack instead of allocating the buffer.
Signed-off-by: Nathan Fotenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Update the architecture vector to indicate that Cooperative Memory
Overcommitment is supported if CONFIG_PPC_SMLPAR is set.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Verify memory entitlement updates can be handled by vio.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is a large patch but the normal code path is not affected. For
non-pSeries platforms the code is ifdef'ed out and for non-CMO enabled
pSeries systems this does not affect the normal code path. Devices that
do not perform DMA operations do not need modification with this patch.
The function get_desired_dma was renamed from get_io_entitlement for
clarity.
Overview
Cooperative Memory Overcommitment (CMO) allows for a set of OS partitions
to be run with less RAM than the aggregate needs of the group of
partitions. The firmware will balance memory between the partitions
and page in/out memory as needed. Based on the number and type of IO
adpaters preset each partition is allocated an amount of memory for
DMA operations and this allocation will be guaranteed to the partition;
this is referred to as the partition's 'entitlement'.
Partitions running in a CMO environment can only have virtual IO devices
present. The VIO bus layer will manage the IO entitlement for the system.
Accounting, at a system and per-device level, is tracked in the VIO bus
code and exposed via sysfs. A set of dma_ops functions are added to
the bus to allow for this accounting.
Bus initialization
At initialization, the bus will calculate the minimum needs of the system
based on providing each device present with a standard minimum entitlement
along with a spare allocation for the bus to handle hotplug events.
If the minimum needs can not be met the system boot will be halted.
Device changes
The significant changes for devices while running under CMO are that the
devices must specify how much dedicated IO entitlement they desire and
must also handle DMA mapping errors that can occur due to constrained
IO memory. The virtual IO drivers are modified to silence errors when
DMA mappings fail for CMO and handle these failures gracefully.
Each devices will be guaranteed a minimum entitlement that can always
be mapped. Devices will specify how much entitlement they desire and
the VIO bus will attempt to provide for this. Devices can change their
desired entitlement level at any point in time to address particular needs
(via vio_cmo_set_dev_desired()), not just at device probe time.
VIO bus changes
The system will have a particular entitlement level available from which
it can provide memory to the devices. The bus defines two pools of memory
within this entitlement, the reserved and excess pools. Each device is
provided with it's own entitlement no less than a system defined minimum
entitlement and no greater than what the device has specified as it's
desired entitlement. The entitlement provided to devices comes from the
reserve pool. The reserve pool can also contain a spare allocation as
large as the system defined minimum entitlement which is used for device
hotplug events. Any entitlement not needed to fulfill the needs of a
reserve pool is placed in the excess pool. Each device is guaranteed
that it can map up to it's entitled level; additional mapping are possible
as long as there is unmapped memory in the excess pool.
Bus probe
As the system starts, each device is given an entitlement equal only
to the system defined minimum entitlement. The reserve pool is equal
to the sum of these entitlements, plus a spare allocation. The VIO bus
also tracks the aggregate desired entitlement of all the devices. If the
system desired entitlement is greater than the size of the reserve pool,
when devices unmap IO memory it will be reserved and a balance operation
will be scheduled for some time in the future.
Entitlement balancing
The balance function tries to fairly distribute entitlement between the
devices in the system with the goal of providing each device with it's
desired amount of entitlement. Devices using more than what would be
ideal will have their entitled set-point adjusted; this will effectively
set a goal for lower IO memory usage as future mappings can fail and
deallocations will trigger a balance operation to distribute the newly
unmapped memory. A fair distribution of entitlement can take several
balance operations to achieve. Entitlement changes and device DLPAR
events will alter the state of CMO and will trigger balance operations.
Hotplug events
The VIO bus allows for changes in system entitlement at run-time via
'vio_cmo_entitlement_update()'. When devices are added the hotplug
device event will be preceded by a system entitlement increase and this
is reversed when devices are removed.
The following changes are made that the VIO bus layer for CMO:
* add IO memory accounting per device structure.
* add IO memory entitlement query function to driver structure.
* during vio bus probe, if CMO is enabled, check that driver has
memory entitlement query function defined. Fail if function not defined.
* fail to register driver if io entitlement function not defined.
* create set of dma_ops at vio level for CMO that will track allocations
and return DMA failures once entitlement is reached. Entitlement will
limited by overall system entitlement. Devices will have a reserved
quantity of memory that is guaranteed, the rest can be used as available.
* expose entitlement, current allocation, desired allocation, and the
allocation error counter for devices to the user through sysfs
* provide mechanism for changing a device's desired entitlement at run time
for devices as an exported function and sysfs tunable
* track any DMA failures for entitled IO memory for each vio device.
* check entitlement against available system entitlement on device add
* track entitlement metrics (high water mark, current usage)
* provide function to reset high water mark
* provide minimum and desired entitlement numbers at a bus level
* provide drivers with a minimum guaranteed entitlement
* balance available entitlement between devices to satisfy their needs
* handle system entitlement changes and device hotplug
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To support Cooperative Memory Overcommitment (CMO), we need to check
for failure from some of the tce hcalls.
These changes for the pseries platform affect the powerpc architecture;
patches for the other affected platforms are included in this patch.
pSeries platform IOMMU code changes:
* platform TCE functions must handle H_NOT_ENOUGH_RESOURCES errors and
return an error.
Architecture IOMMU code changes:
* Calls to ppc_md.tce_build need to check return values and return
DMA_MAPPING_ERROR for transient errors.
Architecture changes:
* struct machdep_calls for tce_build*_pSeriesLP functions need to change
to indicate failure.
* all other platforms will need updates to iommu functions to match the new
calling semantics; they will return 0 on success. The other platforms
default configs have been built, but no further testing was performed.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With the addition of Cooperative Memory Overcommitment (CMO) support
for IBM Power Systems, two fields have been added to the VPA to report
paging statistics. Add support in lparcfg to report them to userspace.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Split the retrieval of processor entitlement data returned in the H_GET_PPP
hcall into its own helper routine.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Update /proc/ppc64/lparcfg to display Cooperative Memory
Overcommitment statistics as reported by the H_GET_MPP hcall. This
also updates the lparcfg interface to allow setting memory entitlement
and weight.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Split the retrieval and setting of processor entitlement and weight into
helper routines. This also removes the printing of the raw values
returned from h_get_ppp, the values are already parsed and printed.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove the extraneous error reporting used when a hcall made from lparcfg fails.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
My previous patch to fix compilation with binutils-2.17 causes
a "file truncated" build error from ld with binutils 2.15 (and
possibly older), and a warning with 2.16 and 2.17.
This fixes it.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Acked-by: Chuck Meade <chuckmeade@mindspring.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch implements support for HW based watchpoint via the
DBSR_DAC (Data Address Compare) facility of the BookE processors.
It does so by interfacing with the existing DABR breakpoint code
and adding the necessary bits and pieces for the new bits to
be properly set or cleared
Signed-off-by: Luis Machado <luisgpm@br.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
A struct sysdev_attribute * parameter was added to the show routine by
commit 4a0b2b4dbe "sysdev: Pass the
attribute to the low level sysdev show/store function".
This eliminates a warning:
arch/powerpc/kernel/sysfs.c:538: warning: initialization from incompatible pointer type
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Stash the first platform string matched by identify_cpu() in
powerpc_base_platform, and supply that to the ELF loader for the value
of AT_BASE_PLATFORM.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
nohz: prevent tick stop outside of the idle loop
On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit
boundary. For example:
u64 val = PAGE_ALIGN(size);
always returns a value < 4GB even if size is greater than 4GB.
The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for
example):
#define PAGE_SHIFT 12
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
...
#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)
The "~" is performed on a 32-bit value, so everything in "and" with
PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary.
Using the ALIGN() macro seems to be the right way, because it uses
typeof(addr) for the mask.
Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in
include/linux/mm.h.
See also lkml discussion: http://lkml.org/lkml/2008/6/11/237
[akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c]
[akpm@linux-foundation.org: fix v850]
[akpm@linux-foundation.org: fix powerpc]
[akpm@linux-foundation.org: fix arm]
[akpm@linux-foundation.org: fix mips]
[akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c]
[akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c]
[akpm@linux-foundation.org: fix powerpc]
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes the old kgdb reminants from ARCH=powerpc and
implements the new style arch specific stub for the common kgdb core
interface.
It is possible to have xmon and kgdb in the same kernel, but you
cannot use both at the same time because there is only one set of
debug hooks.
The arch specific kgdb implementation saves the previous state of the
debug hooks and restores them if you unconfigure the kgdb I/O driver.
Kgdb should have no impact on a kernel that has no kgdb I/O driver
configured.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (49 commits)
powerpc: Fix build bug with binutils < 2.18 and GCC < 4.2
powerpc/eeh: Don't panic when EEH_MAX_FAILS is exceeded
fbdev: Teaches offb about palette on radeon r5xx/r6xx
powerpc/cell/edac: Log a syndrome code in case of correctable error
powerpc/cell: Add DMA_ATTR_WEAK_ORDERING dma attribute and use in Cell IOMMU code
powerpc: Indicate which oprofile counters to use while in compat mode
powerpc/boot: Change spaces to tabs
powerpc: Remove duplicate 6xx option in Kconfig
powerpc: Use PPC_LONG and PPC_LONG_ALIGN in lib/string.S
powerpc: Use PPC_LONG_ALIGN in uaccess.h
powerpc: Add a #define for aligning to a long-sized boundary
powerpc: Fix OF parsing of 64 bits PCI addresses
powerpc: Use WARN_ON(1) instead of __WARN()
powerpc: Fix support for latencytop
powerpc/ps3: Update ps3_defconfig
powerpc/ps3: Add a sub-match id to ps3_system_bus
powerpc: Add a 6xx defconfig
powerpc/dma: Use the struct dma_attrs in iommu code
powerpc/cell: Add support for power button of future IBM cell blades
powerpc/cell: Cleanup sysreset_hack for IBM cell blades
...
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.
I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.
I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.
Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
binutils < 2.18 has a bug that makes it misbehave when taking an
ELF file with all segments at load address 0 as input. This
happens when running "strip" on vmlinux, because of the AT() magic
in this linker script. People using GCC >= 4.2 won't run into
this problem, because the "build-id" support will put some data
into the "notes" segment (at a non-zero load address).
To work around this, we force some data into both the "dummy"
segment and the kernel segment, so the dummy segment will get a
non-zero load address. It's not enough to always create the
"notes" segment, since if nothing gets assigned to it, its load
address will be zero.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Tested-By: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
While running on a system with new hardware and a kernel where the
cpu_specs[] table does not recognize the new hardware, the identify_cpu()
routine will select the default case as it searches through cpu_specs[]
in an attempt to match the real PVR. Once the default case is selected,
non of the oprofile counters and/or fields have been set up or defined.
When identify_cpu() is called once more with the logical PVR, some of
the cpu specific fields are replaced with the exception of the oprofile
related ones. However, in the case where we have actually taken the
default case while searching for the real PVR, we need to tell
oprofile that we are now running in compatibility mode so it can pick up
the correct counters. We do this by setting the oprofile_cpu_type field
to be that taken from the cpu_specs[] for the cpu we are now emulating.
This change will detect that we are now altering the real PVR and determine
if we also need to update the oprofile_cpu_type field.
Signed-off-by: Torez Smith <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The OF parsing code for PCI addresses isn't always treating properly
the address space indication 0b11 (ie. 0x3) as meaning 64 bits
memory space.
This means that it fails to parse addresses for PCI BARs that have
this encoding set by the firmware, which happens on some SLOF
versions and breaks offb palette handling on Powerstation.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
We need to pass the kernel stack pointer instead of the user space
stack pointer in save_stack_trace_tsk().
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Update iommu_alloc() to take the struct dma_attrs and pass them on to
tce_build(). This change propagates down to the tce_build functions of
all the platforms.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Jack Ren and Eric Miao tracked down the following long standing
problem in the NOHZ code:
scheduler switch to idle task
enable interrupts
Window starts here
----> interrupt happens (does not set NEED_RESCHED)
irq_exit() stops the tick
----> interrupt happens (does set NEED_RESCHED)
return from schedule()
cpu_idle(): preempt_disable();
Window ends here
The interrupts can happen at any point inside the race window. The
first interrupt stops the tick, the second one causes the scheduler to
rerun and switch away from idle again and we end up with the tick
disabled.
The fact that it needs two interrupts where the first one does not set
NEED_RESCHED and the second one does made the bug obscure and extremly
hard to reproduce and analyse. Kudos to Jack and Eric.
Solution: Limit the NOHZ functionality to the idle loop to make sure
that we can not run into such a situation ever again.
cpu_idle()
{
preempt_disable();
while(1) {
tick_nohz_stop_sched_tick(1); <- tell NOHZ code that we
are in the idle loop
while (!need_resched())
halt();
tick_nohz_restart_sched_tick(); <- disables NOHZ mode
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
In hindsight we should have done this forever, but ...
/me grabs a large brown paperbag.
Debugged-by: Jack Ren <jack.ren@marvell.com>,
Debugged-by: eric miao <eric.y.miao@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This converts the FSL Book-E PTE access and TLB miss handling to match
with the recent changes to 44x that introduce support for non-atomic PTE
operations in pgtable-ppc32.h and removes write back to the PTE from
the TLB miss handlers. In addition, the DSI interrupt code no longer
tries to fixup write permission, this is left to generic code, and
_PAGE_HWWRITE is gone.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Push the sync below the secondary smp init hold loop and comment its purpose.
This should speed up boot by reducing global traffic during the single-threaded
portion of boot.
Signed-off-by: Sonny Rao <sonnyrao@us.ibm.com>
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
VSX loads and stores will take an alignment exception when the address
is not on a 4 byte boundary.
This add support for these alignment exceptions and will emulate the
requested load or store.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
giveup_vsx didn't save the FPU and VMX regsiters. Change it to be
like giveup_fpr/altivec which save these registers.
Also update call sites where FPU and VMX are already saved to use the
original giveup_vsx (renamed to __giveup_vsx).
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Implement save_stack_trace_tsk on powerpc, so that we can run with
latencytop.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Background from Maynard Johnson:
As of POWER6, a set of 32 common events is defined that must be
supported on all future POWER processors. The main impetus for this
compat set is the need to support partition migration, especially from
processor P(n) to processor P(n+1), where performance software that's
running in the new partition may not be knowledgeable about processor
P(n+1). If a performance tool determines it does not support the
physical processor, but is told (via the
PPC_FEATURE_PSERIES_PERFMON_COMPAT bit) that the processor supports
the notion of the PMU compat set, then the performance tool can
surface just those events to the user of the tool.
PPC_FEATURE_PSERIES_PERFMON_COMPAT indicates that the PMU supports at
least this basic subset of events which is compatible across POWER
processor lines.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Today's linux-next build (powerpc allmodconfig) failed like this:
ERROR: ".save_stack_trace" [tests/backtracetest.ko] undefined!
But save_stack_trace is exported in arch/powerpc/kernel/stacktrace.c
I couldn't figure it out until I noticed these earlier warnings:
arch/powerpc/kernel/stacktrace.c:47: warning: data definition has no type or storage class
arch/powerpc/kernel/stacktrace.c:47: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/powerpc/kernel/stacktrace.c:47: warning: parameter names (without types) in function declaration
I applied the patch below.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: <linuxppc-dev@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For some reason long ago I decided that we should zero out the time base
when we calibrate the decrementer. The problem is that this can be
harmful in SMP systems where the firmware has already synchronized the
time bases on the various cores.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This is some preliminary work to improve TLB management on SW loaded
TLB powerpc platforms. This introduce support for non-atomic PTE
operations in pgtable-ppc32.h and removes write back to the PTE from
the TLB miss handlers. In addition, the DSI interrupt code no longer
tries to fixup write permission, this is left to generic code, and
_PAGE_HWWRITE is gone.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
regs is not used in emulate_fp_pair so remove it.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When the ucontext changed to add the VSX context, this broke backwards
compatibly on swapcontext. swapcontext only compares the ucontext size
passed in from the user to the new kernel ucontext size.
This adds a check against the old ucontext size (with VMX but without
VSX). It also adds some sanity check for ucontexts without VSX, but
where VSX is used according the MSR. Fixes for both 32 and 64bit
processes on 64bit kernels
Kudos to Paulus for noticing.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Choose a more meaningful name for better System.map readability and
autopsy value etc.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Allow an application to enable Strong Access Ordering on specific pages of
memory on Power 7 hardware. Currently, power has a weaker memory model than
x86. Implementing a stronger memory model allows an emulator to more
efficiently translate x86 code into power code, resulting in faster code
execution.
On Power 7 hardware, storing 0b1110 in the WIMG bits of the hpte enables
strong access ordering mode for the memory page. This patchset allows a
user to specify which pages are thus enabled by passing a new protection
bit through mmap() and mprotect(). I have defined PROT_SAO to be 0x10.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This changes the oops and backtrace code to use the new %pS
printk extension to print out symbols rather than manually
calling print_symbol.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Move device_to_mask() to dma-mapping.h because we need to use it from
outside dma_64.c in a later patch.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Update powerpc to use the new dma_*map*_attrs() interfaces. In doing so
update struct dma_mapping_ops to accept a struct dma_attrs and propagate
these changes through to all users of the code (generic IOMMU and the
64bit DMA code, and the iseries and ps3 platform code).
The old dma_*map_*() interfaces are reimplemented as calls to the
corresponding new interfaces.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Make iommu_map_sg take a struct iommu_table. It did so before commit
740c3ce667 (iommu sg merging: ppc: make
iommu respect the segment size limits).
This stops the function looking in the archdata.dma_data for the iommu
table because in the future it will be called with a device that has
no table there.
This also has the nice side effect of making iommu_map_sg() match the
other map functions.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There is dma_mask in of_device upon of_platform_device_create()
but we don't actually set coherent_dma_mask. This may cause weird
behavior of USB subsystem using of_device USB host drivers.
Signed-off-by: Vitaly Bordug <vitb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A recent patch to legacy_serial.c factored out some code by
using the of_match_node() facility to match a node against
an array of possible matches. However, the patch didn't properly
terminate the array causing potential crashes in cases where no
match is found. In addition, the name of the array was poorly
chosen for a static symbol making debugging harder.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Updates the cputable to include the 440 processor found in the
Xilinx Virtex5 FXT FPGA.
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Today's linux-next build (powerpc ppc64_defconfig) failed like this:
arch/powerpc/mm/tlb_64.c: In function 'pgtable_free_now':
arch/powerpc/mm/tlb_64.c:66: error: too many arguments to function 'smp_call_function'
arch/powerpc/kernel/machine_kexec_64.c: In function 'kexec_prepare_cpus':
arch/powerpc/kernel/machine_kexec_64.c:175: error: too many arguments to function 'smp_call_function'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: <linuxppc-dev@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Andrew Morton reported this against linux-next:
ERROR: ".save_stack_trace" [tests/backtracetest.ko] undefined!
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Since Roland's ptrace cleanup starting with commit
f65255e8d5 ("[POWERPC] Use user_regset
accessors for FP regs"), the dump_task_* functions are no longer being
used.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This merges and cleans up some of the ugly copy/to from user code
which is required for the new fpr and vsx layout in the thread_struct.
Also fixes some hard coded buffer sizes and removes a redundant
fpr_flush_to_thread.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
To allow for a single kernel image on e500 v1/v2/mc we need to fixup lwsync
at runtime. On e500v1/v2 lwsync causes an illop so we need to patch up
the code. We default to 'sync' since that is always safe and if the cpu
is capable we will replace 'sync' with 'lwsync'.
We introduce CPU_FTR_LWSYNC as a way to determine at runtime if this is
needed. This flag could be moved elsewhere since we dont really use it
for the normal CPU_FTR purpose.
Finally we only store the relative offset in the fixup section to keep it
as small as possible rather than using a full fixup_entry.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The legacy serial driver does not work with an 8250 type UART that is
described in the device tree with the reg-offset and reg-shift
properties. This change makes legacy_serial ignore these devices.
Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This correctly hooks the VSX dump into Roland McGrath core file
infrastructure. It adds the VSX dump information as an additional elf
note in the core file (after talking more to the tool chain/gdb guys).
This also ensures the formats are consistent between signals, ptrace
and core files.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fix compile error when CONFIG_VSX is enabled.
arch/powerpc/kernel/signal_64.c: In function 'restore_sigcontext':
arch/powerpc/kernel/signal_64.c:241: error: 'i' undeclared (first use in this function)
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Gcc 4.3 produced this warning:
arch/powerpc/kernel/signal_64.c: In function 'restore_sigcontext':
arch/powerpc/kernel/signal_64.c:161: warning: array subscript is above array bounds
This is caused by us copying to aliases of elements of the pt_regs
structure. Make those explicit.
This adds one extra __get_user and unrolls a loop.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch extends the floating point save and restore code to use the
VSX load/stores when VSX is available. This will make FP context
save/restore marginally slower on FP only code, when VSX is available,
as it has to load/store 128bits rather than just 64bits.
Mixing FP, VMX and VSX code will get constant architected state.
The signals interface is extended to enable access to VSR 0-31
doubleword 1 after discussions with tool chain maintainers. Backward
compatibility is maintained.
The ptrace interface is also extended to allow access to VSR 0-31 full
registers.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds the macros for the VSX load/store instruction as most
binutils are not going to support this for a while.
Also add VSX register save/restore macros and vsr[0-63] register definitions.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add a VSX CPU feature. Also add code to detect if VSX is available
from the device tree.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The layout of the new VSR registers and how they overlap on top of the
legacy FPR and VR registers is:
VSR doubleword 0 VSR doubleword 1
----------------------------------------------------------------
VSR[0] | FPR[0] | |
----------------------------------------------------------------
VSR[1] | FPR[1] | |
----------------------------------------------------------------
| ... | |
| ... | |
----------------------------------------------------------------
VSR[30] | FPR[30] | |
----------------------------------------------------------------
VSR[31] | FPR[31] | |
----------------------------------------------------------------
VSR[32] | VR[0] |
----------------------------------------------------------------
VSR[33] | VR[1] |
----------------------------------------------------------------
| ... |
| ... |
----------------------------------------------------------------
VSR[62] | VR[30] |
----------------------------------------------------------------
VSR[63] | VR[31] |
----------------------------------------------------------------
VSX has 64 128bit registers. The first 32 regs overlap with the FP
registers and hence extend them with and additional 64 bits. The
second 32 regs overlap with the VMX registers.
This commit introduces the thread_struct changes required to reflect
this register layout. Ptrace and signals code is updated so that the
floating point registers are correctly accessed from the thread_struct
when CONFIG_VSX is enabled.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make load_up_fpu and load_up_altivec callable so they can be reused by
the VSX code.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Move the altivec_unavailable code, to make room at 0xf40 where the
vsx_unavailable exception will be.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We are going to change where the floating point registers are stored
in the thread_struct, so in preparation add some macros to access the
floating point registers. Update all code to use these new macros.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If we set the SPE MSR bit in save_user_regs we can blow away the VEC
bit. This doesn't matter in reality as they are in fact the same bit
but looks bad.
Also, when we add VSX in a later patch, we need to be able to set two
separate MSR bits here.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Use an alternative feature section in _switch. There are three cases
handled here, either we don't have an SLB, in which case we jump over the
entire code section, or if we do we either do or don't have 1TB segments.
Boot tested on Power3, Power5 and Power5+.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The current feature section logic only supports nop'ing out code, this means
if you want to choose at runtime between instruction sequences, one or both
cases will have to execute the nop'ed out contents of the other section, eg:
BEGIN_FTR_SECTION
or 1,1,1
END_FTR_SECTION_IFSET(FOO)
BEGIN_FTR_SECTION
or 2,2,2
END_FTR_SECTION_IFCLR(FOO)
and the resulting code will be either,
or 1,1,1
nop
or,
nop
or 2,2,2
For small code segments this is fine, but for larger code blocks and in
performance criticial code segments, it would be nice to avoid the nops.
This commit starts to implement logic to allow the following:
BEGIN_FTR_SECTION
or 1,1,1
FTR_SECTION_ELSE
or 2,2,2
ALT_FTR_SECTION_END_IFSET(FOO)
and the resulting code will be:
or 1,1,1
or,
or 2,2,2
We achieve this by extending the existing FTR macros. The current feature
section semantic just becomes a special case, ie. if the else case is empty
we nop out the default case.
The key limitation is that the size of the else case must be less than or
equal to the size of the default case. If the else case is smaller the
remainder of the section is nop'ed.
We let the linker put the else case code in with the rest of the text,
so that relative branches from the else case are more likley to link,
this has the disadvantage that we can't free the unused else cases.
This commit introduces the required macro and linker script changes, but
does not enable the patching of the alternative sections.
We also need to update two hand-made section entries in reg.h and timex.h
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The logic to patch CPU feature sections lives in cputable.c, but these days
it's used for CPU features as well as firmware features. Move it into
it's own file for neatness and as preparation for some additions.
While we're moving the code, we pull the loop body logic into a separate
routine, and remove a comment which doesn't apply anymore.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A bunch of code has hard-coded the value for a "nop" instruction, it
would be nice to have a #define for it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently create_branch() creates a branch instruction for you, and
patches it into the call site. In some circumstances it would be nice
to be able to create the instruction and patch it later, and also some
code might want to check for errors in the branch creation before
doing the patching. A future commit will change create_branch() to
check for errors.
For callers that don't care, replace create_branch() with
patch_branch(), which just creates the branch and patches it directly.
While we're touching all the callers, change to using unsigned int *,
as this seems to match usage better. That allows (and requires) us to
remove the volatile in the definition of vector in powermac/smp.c and
mpc86xx_smp.c, that's correct because now that we're passing vector as
an unsigned int * the compiler knows that it's value might change
across the patch_branch() call.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently have a few routines for patching code in asm/system.h, because
they didn't fit anywhere else. I'd like to clean them up a little and add
some more, so first move them into a dedicated C file - they don't need to
be inlined.
While we're moving the code, drop create_function_call(), it's intended
caller never got merged and will be replaced in future with something
different.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Refactor common code between ppc32 and ppc64 module handling into a
shared filed.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add the bits to the architecture-vec so that ibm,client-architecture
lets the firmware know we support the 2.06 architecture.
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add an entry for Power7 architected mode and add "(raw)" to Power7 raw
mode to distinguish it more clearly.
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Add a cputable entry for the POWER7 processor.
Also tell firmware that we know about POWER7.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There are now two potential callers of machine_crash_shutdown,
so increase the limit accordingly.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
It's never used and the comments refer to nonatomic and retry
interchangably. So get rid of it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This converts ppc to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().
ppc loses the timeout functionality of smp_call_function_mask() with
this change, as the generic code does not provide that.
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch is based on work done by Madhvesh. R. Sulibhavi back in
March 2007.
We refactor some of the single step handling since it differs between
"classic" and "booke" powerpc cores.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* Mark __flush_icache_range as a function that can't be probed since its
used by the kprobe code.
* Fix an issue with single stepping and async exceptions. We need to
ensure that we dont get an async exception (external, decrementer, etc)
while we are attempting to single step the probe point.
Added a check to ensure we only handle a single step if its really
intended for the instruction in question.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
If we have an L2CSR register (e500mc) we need to flush the L2 before going
to nap. We use the HW flush mechanism provided in that register.
The code reuses the CPU_FTR_604_PERF_MON bit as it is no longer used by
any code in the kernel. Additionally we didn't reuse the exist L2CR
feature bit as this is intended for the 7xxx L2CR register and L2CSR
is part of the new Freescale "Book-E" registers.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The e500 core enter DOZE/NAP power-saving modes when the core go to
cpu_idle routine.
The power management default running mode is DOZE, If the user
echo 1 > /proc/sys/kernel/powersave-nap
the system will change to NAP running mode.
Signed-off-by: Dave Liu <daveliu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Record the address of the mcount call-site. Currently all archs except sparc64
record the address of the instruction following the mcount call-site. Some
general cleanups are entailed. Storing mcount addresses in rec->ip enables
looking them up in the kprobe hash table later on to check if they're kprobe'd.
Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Cc: davem@davemloft.net
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
KAMEZAWA Hiroyuki and Oleg Nesterov point out that since the commit
557ed1fa26 ("remove ZERO_PAGE") removed
the ZERO_PAGE from the VM mappings, any users of get_user_pages() will
generally now populate the VM with real empty pages needlessly.
We used to get the ZERO_PAGE when we did the "handle_mm_fault()", but
since fault handling no longer uses ZERO_PAGE for new anonymous pages,
we now need to handle that special case in follow_page() instead.
In particular, the removal of ZERO_PAGE effectively removed the core
file writing optimization where we would skip writing pages that had not
been populated at all, and increased memory pressure a lot by allocating
all those useless newly zeroed pages.
This reinstates the optimization by making the unmapped PTE case the
same as for a non-existent page table, which already did this correctly.
While at it, this also fixes the XIP case for follow_page(), where the
caller could not differentiate between the case of a page that simply
could not be used (because it had no "struct page" associated with it)
and a page that just wasn't mapped.
We do that by simply returning an error pointer for pages that could not
be turned into a "struct page *". The error is arbitrarily picked to be
EFAULT, since that was what get_user_pages() already used for the
equivalent IO-mapped page case.
[ Also removed an impossible test for pte_offset_map_lock() failing:
that's not how that function works ]
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The new e500mc core from Freescale is based on the e500v2 but with the
following changes:
* Supports only the Enhanced Debug Architecture (DSRR0/1, etc)
* Floating Point
* No SPE
* Supports lwsync
* Doorbell Exceptions
* Hypervisor
* Cache line size is now 64-bytes (e500v1/v2 have a 32-byte cache line)
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
A recent commit added support for the new 440x6 and 464 cores that have the
added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
TLBs. The new bits were cleared in the finish_tlb_load function, however a
similar bit of code was missed in the DataStorage interrupt vector.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There are no in-tree uses of the export any more and in linux-next there
is a change that exports it globally which causes warnings:
WARNING: vmlinux: 'console_drivers' exported twice. Previous export was in vmlinux
and in one case (mpc85xx_defconfig) a build error:
kernel/built-in.o: In function `__crc_console_drivers':
(*ABS*+0x1eb0e6f5): multiple definition of `__crc_console_drivers'
So remove the export now. Also, there is no longer any need to include
linux/console.h.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:
http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html
This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE. To fix
this we add the use the save/restore code from gcc and simplified it down
for our needs (integer only).
Additionally, we have to link this code into each module. The other
solution was to add EXPORT_SYMBOL() which meant going through the
trampoline which seemed nonsensical for these out-of-line routines.
Finally, we add some checks to prom_init_check.sh to ignore the
out-of-line save/restore functions.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
debugfs_create_file() returns a non-NULL (non-zero) value in case of
success, not a NULL value.
This fixes this non-critical boot-time debugging error message:
[ 1.316386] calling irq_debugfs_init+0x0/0x50
[ 1.316399] initcall irq_debugfs_init+0x0/0x50 returned -12 after 0 msecs
[ 1.316411] initcall irq_debugfs_init+0x0/0x50 returned with error code -12
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This reverts commit acb0142bf0.
AMCC has indicated that the PPC 460GT does have FPU support. This
revert enables the FPU for those chips again.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
When I changed irq_alloc_host() to take an of_node
(52964f87c64e6c6ea671b5bf3030fb1494090a48: "Add an optional
device_node pointer to the irq_host"), I botched the reference
counting semantics.
Stephen pointed out that it's irq_alloc_host()'s business if
it needs to take an additional reference to the device_node,
the caller shouldn't need to care.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This eliminates this minor boot-time debugging error message:
[ 1.316451] calling add_pcspkr+0x0/0x84
[ 1.316478] initcall add_pcspkr+0x0/0x84 returned -19 after 0 msecs
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
During the next merge window, pci_name()'s return value will become
const, so use the new dev_set_name() instead to avoid the warning (from
linux-next):
arch/powerpc/kernel/pci_64.c: In function 'of_create_pci_dev':
arch/powerpc/kernel/pci_64.c:193: warning: passing argument 1 of 'sprintf' discards qualifiers from pointer target type
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When building a signal or a ucontext, we can incorrectly set the MSR_VEC
bit of the kernel pt_regs->msr before returning to userspace if the task
-ever- used VMX.
This can lead to funny result if that stack used it in the past, then
"lost" it (ie. it wasn't enabled after a context switch for example)
and then called get_context. It can end up with VMX enabled and the
registers containing values from some other task.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On machines with more than one exception level any system register that
might be modified by the "normal" exception level needs to be saved and
restored on taking a higher level exception. We already are saving
and restoring ESR and DEAR.
For critical level add SRR0/1.
For debug level add CSRR0/1 and SRR0/1.
For machine check level add DSRR0/1, CSRR0/1, and SRR0/1.
On FSL Book-E parts we always save/restore the MAS registers for critical,
debug, and machine check level exceptions. On 44x we always save/restore
the MMUCR.
Additionally, we save and restore the ksp_limit since we have to adjust it
for each exception level.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
* Cleanup the code a bit my allocating an INT_FRAME on our exception
stack there by make references go from GPR11-INT_FRAME_SIZE(r8) to
just GPR11(r8)
* simplify {lvl}_transfer_to_handler code by moving the copying of the
temp registers we use if we come from user space into the PROLOG
* If the exception came from kernel mode copy thread_info flags,
preempt, and task pointer from the process thread_info.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
For the additonal exception levels (critical, debug, machine check) on
40x/book-e we were using "static" allocations of the stack in the
associated head.S.
Move to a runtime allocation to make the code a bit easier to read as
we mimic how we handle IRQ stacks. Its also a bit easier to setup the
stack with a "dummy" thread_info in C code.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
This patch cleans up the ftrace code in PowerPC based on the comments from
Michael Ellerman.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: proski@gnu.org
Cc: a.p.zijlstra@chello.nl
Cc: Pekka Paalanen <pq@iki.fi>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: linuxppc-dev@ozlabs.org
Cc: Soeren Sandmann Pedersen <sandmann@redhat.com>
Cc: paulus@samba.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds full support for ftrace for PowerPC (both 64 and 32 bit).
This includes dynamic tracing and function filtering.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Since commit "85xx: Add support for relocatable kernel (and
booting at non-zero)" (37dd2badcf),
PHYSICAL_START is #defined as kernstart_addr if RELOCATABLE
and FLATMEM is enabled.
PHYSICAL_START is used in prom_init.c and so kernstart_addr
needs to be added to the list of allowed symbols that
prom_init.c can access.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
func_descr_t->entry is already an unsigned long. Mea culpa.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This works around bugs in older binutils' objcopy.
The placement of these sections does not really matter,
but it confused the buggy old BFD libraries.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 140b932f8c ("Create modalias file
in sysfs for of_platform bus") needs this to avoid breaking the sparc
builds.
Just move the code and add whitespace around some binary operators.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This provides a way to defer processing of an interrupt that wakes the
processor out of sleep mode. On 32-bit platforms that use an
interrupt to wake the processor, we have to have interrupts enabled in
hardware at the point where we go to sleep, otherwise the processor
will never wake up. However, because interrupts are logically
disabled at this point, we don't want to process the interrupt
straight away.
This is handled by setting the _TLF_SLEEPING flag. When we get an
interrupt and _TLF_SLEEPING is set, we firstly clear the MSR_EE
(external interrupt enable) bit in the saved MSR value, and secondly
we then return to the address in the link register, like we do for
_TLF_NAPPING, but without actually handling the interrupt.
Note that this is handled somewhat differently on powerbooks, so this
new code will only be used on non-Apple machines.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make a few things static in lparcfg.c
Make init and exit routines static in rtas_flash.c
Make things static in rtas_pci.c
Make some functions static in rtas.c
Make fops static in rtas-proc.c
Remove unneeded extern for do_gtod in smp.c
Make clocksource_init() static in time.c
Make last_tick_len and ticklen_to_xs static in time.c
Move the declaration of the pvr per-cpu into smp.h
Make kexec_smp_down() and kexec_stack static in machine_kexec_64.c
Don't return void in arch_teardown_msi_irqs() in msi.c
Move declaration of GregorianDay()into asm/time.h
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We use the low bits of regs->trap as flag bits. We already indicate
critical and machine check level exceptions via this mechanism. Extend it
to indicate debug level exceptions.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Replace TIF_RESTORE_SIGMASK with TLF_RESTORE_SIGMASK and define
our own set_restore_sigmask() function. This saves the costly
SMP-safe set_bit operation, which we do not need for the sigmask
flag since TIF_SIGPENDING always has to be set too.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 76bc080ef5 ("POWERPC] Make default
cputable entries reflect selected CPU family") added default entries
for the e200 and e500 families, but missed a closing brace on those
entries, as pointed out by David Gibson. This adds the closing braces.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This printk() appears twice in the same function. Only the latter one
in the inval_range: section appears to be legitimate.
Signed-off-by: Nate Case <ncase@xes-inc.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove duplicate #include of <asm/prom.h> in
arch/powerpc/kernel/btext.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves lockdep_init() to before udbg_early_init() as the later
can call things that acquire spinlocks etc... This also makes printk
safer to use earlier.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When debugging early boot problems, it's common to sprinkle printk's
all over the place. However, on 64-bit powerpc, this can lead to
memory corruption if done too early due to the PACA pointer and
lockdep core not being initialized.
This adds some comments to early_setup() that document when it is
safe to do so in order to save time for whoever has to debug that
stuff next.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
When doing lockdep, I had two patches to initialize paca->_current
early, one bogus, and one correct. Unfortunately both got merged
as the bad one ended up being part of the main lockdep patch by
mistake. This causes memory corruption at boot. This removes
the offending code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Changes the cputable so that various CPU families that have an exclusive
CONFIG_ option have a more sensible default entry to use if the specific
processor hasn't been identified.
This makes the kernel more generally useful when booted on an unknown
PVR for things like new 4xx variants.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The new 440x6 core used on AMCC 460EX/GT introduces new storage attibure
fields to the TLB2 word. Those are:
Bit 11 12 13 14 15
WL1 IL1I IL1D IL2I IL2D
With these bits the cache (L1 and L2) can be configured in a more flexible
way, instruction- and data-cache independently now. The "old" I and W bits
are still available and setting these old bits will automically set these
new bits too (for backward compatibilty).
The current code does not clear these fields resulting in disabling the cache
by chance. This patch now makes sure that these new bits are cleared when
the TLB2 word is written.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
This replaces the duplicated arch-specific versions of "sys_pipe()" with
one unified implementation. This removes almost 250 lines of duplicated
code.
It's marked __weak, so that *if* an architecture wants to override the
default implementation it can do so by simply having its own replacement
version, since many architectures use alternate calling conventions for
the 'pipe()' system call for legacy reasons (ie traditional UNIX
implementations often return the two file descriptors in registers)
I still haven't changed the cris version even though Linus says the BKL
isn't needed. The arch maintainer can easily do it if there are really
no obstacles.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[POWERPC] Bolt in SLB entry for kernel stack on secondary cpus
[POWERPC] PS3: Update ps3_defconfig
[POWERPC] PS3: Remove unsupported wakeup sources
[POWERPC] PS3: Make ps3_virq_setup and ps3_virq_destroy static
[POWERPC] PS3: Add time include to lpm
[POWERPC] Fix slb.c compile warnings
[POWERPC] Xilinx: Fix compile warnings
[POWERPC] Squash build warning for print of resource_size_t in fsl_soc.c
[RAPIDIO] fix current kernel-doc notation
[POWERPC] 86xx: mpc8610_hpcd: add support for PCI Express x8 slot
Fix a potential issue in mpc52xx uart driver
[POWERPC] mpc5200: Allow for fixed speed MII configurations
[POWERPC] 86xx: Fix the wrong serial1 interrupt for 8610 board
This fixes a regression reported by Kamalesh Bulabel where a POWER4
machine would crash because of an SLB miss at a point where the SLB
miss exception was unrecoverable. This regression is tracked at:
http://bugzilla.kernel.org/show_bug.cgi?id=10082
SLB misses at such points shouldn't happen because the kernel stack is
the only memory accessed other than things in the first segment of the
linear mapping (which is mapped at all times by entry 0 of the SLB).
The context switch code ensures that SLB entry 2 covers the kernel
stack, if it is not already covered by entry 0. None of entries 0
to 2 are ever replaced by the SLB miss handler.
Where this went wrong is that the context switch code assumes it
doesn't have to write to SLB entry 2 if the new kernel stack is in the
same segment as the old kernel stack, since entry 2 should already be
correct. However, when we start up a secondary cpu, it calls
slb_initialize, which doesn't set up entry 2. This is correct for
the boot cpu, where we will be using a stack in the kernel BSS at this
point (i.e. init_thread_union), but not necessarily for secondary
cpus, whose initial stack can be allocated anywhere. This doesn't
cause any immediate problem since the SLB miss handler will just
create an SLB entry somewhere else to cover the initial stack.
In fact it's possible for the cpu to go quite a long time without SLB
entry 2 being valid. Eventually, though, the entry created by the SLB
miss handler will get overwritten by some other entry, and if the next
access to the stack is at an unrecoverable point, we get the crash.
This fixes the problem by making slb_initialize create a suitable
entry for the kernel stack, if we are on a secondary cpu and the stack
isn't covered by SLB entry 0. This requires initializing the
get_paca()->kstack field earlier, so I do that in smp_create_idle
where the current field is initialized. This also abstracts a bit of
the computation that mk_esid_data in slb.c does so that it can be used
in slb_initialize.
Signed-off-by: Paul Mackerras <paulus@samba.org>
As TICK_LENGTH_SHIFT is used for more than just the tick length, the name
isn't quite approriate anymore, so this renames it to NTP_SCALE_SHIFT.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This changes time_freq to a 64bit value and makes it static (the only outside
user had no real need to modify it). Intermediate values were already 64bit,
so the change isn't that big, but it saves a little in shifts by replacing
SHIFT_NSEC with TICK_LENGTH_SHIFT. PPM_SCALE is then used to convert between
user space and kernel space representation.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds a minimalistic braille screen reader support. This is meant to
be used by blind people e.g. on boot failures or when / cannot be mounted
etc and thus the userland screen readers can not work.
[akpm@linux-foundation.org: fix exports]
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jiri Kosina <jikos@jikos.cz>
Cc: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit edd8ce6743 (Use extended crashkernel
command line on ppc64), changed the logic in reserve_crashkernel()
which deals with the crashkernel= command line option.
This introduced a bug in the case when there is no crashkernel= option,
or it is incorrect. We would fall through and calculate the crash_size
based on the existing values in crashk_res. If both start and end are 0,
the default, we calculate the crash_size as 1 byte - which is wrong.
Rework the logic so that we use crashk_res, regardless of whether it's
set by the command line or via the device tree (see prom.c). Then check
if we have an empty range (end == start), and if so make sure to set
both end and start to zero (this is checked in machine_kexec_64.c). Then
we calculate the crash_size once we know we have a non-zero range.
Finally we always want to warn the user if they specify a base != 32MB,
so remove the special case for that in the command line parsing case.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The current_thread_info() macro, used by preempt_count(), assumes the
base address and size of the stack are THREAD_SIZE aligned.
The emergency stack currently isn't either of these things, which
could potentially cause problems anytime we're running on the
emergency stack. That includes when we detect a bad kernel stack
pointer, and also during early_setup_secondary().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[RAPIDIO] Change RapidIO doorbell source and target ID field to 16-bit
[RAPIDIO] Add RapidIO connection info print out and re-training for broken connections
[RAPIDIO] Add serial RapidIO controller support, which includes MPC8548, MPC8641
[RAPIDIO] Add RapidIO node probing into MPC86xx_HPCN board id table
[RAPIDIO] Add RapidIO node into MPC8641HPCN dts file
[RAPIDIO] Auto-probe the RapidIO system size
[RAPIDIO] Add OF-tree support to RapidIO controller driver
[RAPIDIO] Add RapidIO multi mport support
[RAPIDIO] Move include/asm-ppc/rio.h to asm-powerpc
[RAPIDIO] Add RapidIO option to kernel configuration
[RAPIDIO] Change RIO function mpc85xx_ to fsl_
[POWERPC] Provide walk_memory_resource() for powerpc
[POWERPC] Update lmb data structures for hotplug memory add/remove
[POWERPC] Hotplug memory remove notifications for powerpc
[POWERPC] windfarm: Add PowerMac 12,1 support
[POWERPC] Fix building of pmac32 when CONFIG_NVRAM=m
[POWERPC] Add IRQSTACKS support on ppc32
[POWERPC] Use __always_inline for xchg* and cmpxchg*
[POWERPC] Add fast little-endian switch system call
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data
be setup before gluing PDE to main tree.
Add correct ->owner to proc_fops to fix reading/module unloading race.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This initializes the RapidIO controller driver using addresses and
interrupt numbers obtained from the firmware device tree, rather than
using hardcoded constants.
Signed-off-by: Zhang Wei <wei.zhang@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes it possible to use separate stacks for hard and soft IRQs
on 32-bit powerpc as well as on 64-bit. The code for 32-bit is just
the 32-bit analog of the 64-bit code.
* Added allocation and initialization of the irq stacks. We limit the
stacks to be in lowmem for ppc32.
* Implemented ppc32 versions of call_do_softirq() and call_handle_irq()
to switch the stack pointers
* Reworked how we do stack overflow detection. We now keep around the
limit of the stack in the thread_struct and compare against the limit
to see if we've overflowed. We can now use this on ppc64 if desired.
[ paulus@samba.org: Fixed bug on 6xx where we need to reload r9 with the
thread_info pointer. ]
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a system call on 64-bit platforms for switching between
little-endian and big-endian modes that is much faster than doing a
prctl call. This system call is handled as a special case right at
the start of the system call entry code, and because it is a special
case, it uses a system call number which is out of the range of
normal system calls, namely 0x1ebe.
Measurements with lmbench on a 4.2GHz POWER6 showed no measurable
change in the speed of normal system calls with this patch.
Switching endianness with this new system call takes around 60ns on a
4.2GHz POWER6, compared with around 300ns to switch endian mode with a
prctl. This can provide a significant performance advantage for
emulators for little-endian architectures that want to switch between
big-endian and little-endian mode frequently, e.g. because they are
generating instructions sequences on the fly and they want to run
those sequences in little-endian mode.
The other thing about this system call is that it doesn't clobber as
many registers as a normal system call. It only clobbers r12.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This functionality is definitely experimental, but is capable of running
unmodified PowerPC 440 Linux kernels as guests on a PowerPC 440 host. (Only
tested with 440EP "Bamboo" guests so far, but with appropriate userspace
support other SoC/board combinations should work.)
See Documentation/powerpc/kvm_440.txt for technical details.
[stephen: build fix]
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The AMCC 460GT doesn't have an FPU so let's not enable support for it.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
This splits cell io-workaround code into spider-pci dependent code and
a generic part, and also moves io-workarounds initialization into
cell_setup_phb.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The udbg console should be safe to call basically at any time after boot.
It does not need any per-cpu resources or for the cpu to be online, as
long as there is a udbg_putc routine hooked up it should work. So mark it
as CON_ANYTIME.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Because the udbg_console has CON_ENABLED set, it's possible that when we
register it with the console code the index won't be set. This leads to
slightly confusing boot messages like:
[ 0.000000] console [udbg-1] enabled
We could remove CON_ENABLED, but we don't want to do that, we always
want the udbg console to be activated, even if the user specified some
other console on the command line.
The simplest fix seems to be just to set the index to 0 by hand. There
is no issue with duplicate udbg consoles, as we guard against registering
multiple times in register_early_udbg_console().
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds the required functionality to fill in all pacas at runtime.
With NR_CPUS=1024
text data bss dec hex filename
137 1704032 0 1704169 1a00e9 arch/powerpc/kernel/paca.o :Before
121 1179744 524288 1704153 1a00d9 arch/powerpc/kernel/paca.o :After
Also remove unneeded #includes from arch/powerpc/kernel/paca.c
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* Removed get_msr(), get_srr0(), and get_srr1() - not used anywhere
* Use STACK_FRAME_OVERHEAD instead of magic number
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
As BenH said the other day, it is an "accident" that prom_init.o is
linked with the rest of the kernel. The truth is a little more
subtle, prom_init isn't truly bootloader, it does access kernel data
in a few places.
What we can do is discourage people from adding new code that accesses
data outside of prom_init. And hence this patch; from the script:
# This script checks prom_init.o to see what external symbols it
# is using, if it finds symbols not in the whitelist it returns
# an error. The point of this is to discourage people from
# intentionally or accidentally adding new code to prom_init.c
# which has side effects on other parts of the kernel.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* Removed TI_EXECDOMAIN define as its not used anywhere
* Use STACK_INT_FRAME_SIZE to allow common define of INT_FRAME_SIZE
* Define TI_CPU on both ppc32 & ppc64 (removes an ifdef).
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Use (31-THREAD_SHIFT) to get to thread_info from stack pointer. This makes
the code a bit easier to read and more robust if we ever change THREAD_SHIFT.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove the inclusion of asm-offsets.h from stacktrace.c. It isn't
supposed to be included in C code and it causes problems with multiple
definitions of things.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Added support to allow an 85xx kernel to be run from a non-zero physical
address (useful for cooperative asymmetric multiprocessing situations and
kdump). The support can be configured at compile time by setting
CONFIG_PAGE_OFFSET, CONFIG_KERNEL_START, and CONFIG_PHYSICAL_START as
desired.
Alternatively, the kernel build can set CONFIG_RELOCATABLE. Setting this
config option causes the kernel to determine at runtime the physical
addresses of CONFIG_PAGE_OFFSET and CONFIG_KERNEL_START. If
CONFIG_RELOCATABLE is set, then CONFIG_PHYSICAL_START has no meaning.
However, CONFIG_PHYSICAL_START will always be used to set the LOAD program
header physical address field in the resulting ELF image.
Currently we are limited to running at a physical address that is a
multiple of 256M. This is due to how we map TLBs to cover
lowmem. This should be fixed to allow 64M or maybe even 16M alignment
in the future. It is considered an error to try and run a kernel at a
non-aligned physical address.
All the magic for this support is accomplished by proper initialization
of the kernel memory subsystem and use of ARCH_PFN_OFFSET.
The use of ARCH_PFN_OFFSET only affects normal memory and not IO mappings.
ioremap uses map_page and isn't affected by ARCH_PFN_OFFSET.
/dev/mem continues to allow access to any physical address in the system
regardless of how CONFIG_PHYSICAL_START is set.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The powerpc kernel stacks need to be naturally aligned, as they
contain the thread info at the bottom, which is obtained by
clearing the low bits of the stack pointer.
However, when using 64K pages, the stack is smaller than a page,
so we use kmalloc to allocate it, but that doesn't provide the
alignment guarantee we need.
It appeared to work so far... until one enables SLUB debugging
which then returns unaligned pointers. Ooops...
This fixes it by using a slab cache with enforced alignment. It
relies on my previous patch that adds a thread_info_cache_init()
callback.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This reverts commit e4cc58944c, as
requested by Roland McGrath, because compat_ptrace_request (added in
commit e16b278164, "ptrace:
compat_ptrace_request siginfo") now handles this case.
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (202 commits)
[POWERPC] Fix compile breakage for 64-bit UP configs
[POWERPC] Define copy_siginfo_from_user32
[POWERPC] Add compat handler for PTRACE_GETSIGINFO
[POWERPC] i2c: Fix build breakage introduced by OF helpers
[POWERPC] Optimize fls64() on 64-bit processors
[POWERPC] irqtrace support for 64-bit powerpc
[POWERPC] Stacktrace support for lockdep
[POWERPC] Move stackframe definitions to common header
[POWERPC] Fix device-tree locking vs. interrupts
[POWERPC] Make pci_bus_to_host()'s struct pci_bus * argument const
[POWERPC] Remove unused __max_memory variable
[POWERPC] Simplify xics direct/lpar irq_host setup
[POWERPC] Use pseries_setup_i8259_cascade() in pseries_mpic_init_IRQ()
[POWERPC] Turn xics_setup_8259_cascade() into a generic pseries_setup_i8259_cascade()
[POWERPC] Move xics_setup_8259_cascade() into platforms/pseries/setup.c
[POWERPC] Use asm-generic/bitops/find.h in bitops.h
[POWERPC] 83xx: mpc8315 - fix USB UTMI Host setup
[POWERPC] 85xx: Fix the size of qe muram for MPC8568E
[POWERPC] 86xx: mpc86xx_hpcn - Temporarily accept old dts node identifier.
[POWERPC] 86xx: mark functions static, other minor cleanups
...
603 CPUs have the same issue that some 750 CPUs have in that they can crash
in funny ways if a store from an FPU register instruction is executed on a
register that has never been initialized since power on. This patch fixes
it by making sure all FP registers have been properly initialized at kernel
boot.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Use the generic pci_enable_resources() instead of the arch-specific code.
The generic version is functionally equivalent, but uses dev_printk.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Define the copy_siginfo_from_user32 entry point for powerpc, so
that generic CONFIG_COMPAT code can call it. We already had the
code rolled into compat_sys_rt_sigqueueinfo, this just moves it
out into the canonical function that other arch's define.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Current versions of gdb require a working implementation of
PTRACE_GETSIGINFO for proper watchpoint support. Since struct siginfo
contains pointers it must be converted when passed to a 32-bit debugger.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
None of these files use any of the functionality promised by
asm/semaphore.h. It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
This adds the low level irq tracing hooks to the powerpc architecture
needed to enable full lockdep functionality.
This is partly based on Johannes Berg's initial version. I removed
the asm trampoline that isn't needed (thus improving performance) and
modified all sorts of bits and pieces, reworking most of the assembly,
etc...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds stacktrace support for powerpc, which will be needed for
lockdep.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves various definitions used all over the place to parse stack
frames to ptrace.h so only one definition is needed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Lockdep found out that we can occasionally take the device-tree
lock for reading from softirq time (from rtas_token called
by the rtas real time clock code called by the NTP code),
while we take it occasionally for writing without masking
interrupts. The combination of those two can thus deadlock.
While some of those cases of interrupt read lock could be fixed
(such as caching the RTAS tokens) I figured that taking the
lock for writing is so rare (device-tree modification) that we
may as well penalize that case and allow reading from interrupts.
Thus, this turns all the writers to take the lock with irqs
masked to avoid the situation.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* Add special cases for pplus and prep to ide_default_{irq,io_base}()
(+ FIXMEs about the need to use IDE platform host driver instead).
* Remove no longer needed ppc_ide_md and struct ide_machdep_calls.
* Then remove <linux/ide.h> include from:
- arch/powerpc/kernel/setup_32.c
- arch/ppc/kernel/ppc_ksyms.c
- arch/ppc/kernel/setup.c
- arch/ppc/platforms/pplus.c
- arch/ppc/platforms/prep_setup.c
There should be no functional changes caused by this patch.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
global_dbcr0 needs to be a per cpu set of save areas instead of a single
global on all processors.
Also, we switch to using DBCR0_IDM to determine if the user space app is
being debugged as its a more consistent way. In the future we should
support features like hardware breakpoint and watchpoints which will
have DBCR0_IDM set but not necessarily DBCR0_IC (single step).
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The architecture allows for "Book-E" style debug interrupts to either go
to critial interrupts of their own debug interrupt level. To allow for
a dynamic kernel to support machines of either type we want to be able to
compile in the interrupt handling code for both exception levels.
Towards this goal we renamed the debug handling macros to specify the
interrupt level in their name (DEBUG_CRIT_EXCEPTION/DebugCrit and
DEBUG_DEBUG_EXCEPTION/DebugDebug).
Additionally, on the Freescale Book-e parts we expanded the exception
stacks to cover the maximum case of needing three exception stacks (normal,
machine check and debug).
There is some kernel text space optimization to be gained if a kernel is
configured for a specific Freescale implementation but we aren't handling
that now to allow for the single kernel image support.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This changes the way we calculate how much space to reserve for the
pHyp dump. Currently we reserve 256MB only. With this change, the
code first checks to see if an amount has been specified on the boot
command line with the "phyp_dump_reserve_size" option, and if so, uses
that much.
Otherwise it computes 5% of total ram and rounds it down to a multiple
of 256MB, and uses the larger of that or 256MB.
This is for large systems with a lot of memory (10GB or more). The
aim is to have more space available for the kernel on reboot on
machines with more resources. Although the dump will be collected
pretty fast and the memory released really early on allowing the
machine to have the full memory available, this alleviates any issues
that can be caused by having way too little memory on very very large
systems during those few minutes.
Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We can set LOAD_OFFSET and use the AT attribute on sections and the
linker will properly set the physical address of the LOAD program
header for us.
This allows us to know how the PHYSICAL_START the user configured a
kernel with by just looking at the resulting vmlinux ELF.
This is pretty much stolen from how x86 does things in their linker
scripts.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* PAGE_OFFSET is not always the start of code, use _stext instead.
* grab PAGE_SIZE and KERNELBASE from asm/page.h like ppc64 does. Makes the
code a bit more common and provide a single place to manipulate the
defines for things like kdump.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* Determine the RPN we are running the kernel at runtime rather
than using compile time constant for initial TLB
* Cleanup adjust_total_lowmem() to respect memstart_addr and
be a bit more clear on variables that are sizes vs addresses.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Fedora 9 works on Efika without the separate 'device-tree supplement',
thanks to the kernel's own fixups. With one exception -- because 'CHRP'
still appears on the 'machine:' line in /proc/cpuinfo, the installer
misdetects the platform and misconfigures yaboot, putting it into a PReP
boot partition instead of in the /boot filesystem where the Efika's
firmware could find it.
The kernel's fixups for Efika already correct one instance of 'chrp', in
the 'device_type' property. This fixes it in the 'CODEGEN,description'
property too, since that's what's exposed to userspace in /proc/cpuinfo.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes the handling of the preempt count when switching
interrupt stacks so that HW interrupt properly get the softirq
mask copied over from the previous stack.
It also initializes the softirq stack preempt_count to 0 instead
of SOFTIRQ_OFFSET, like x86, as __do_softirq() does the increment,
and we hit some lockdep checks if we have it twice.
That means we do run for a little while off the softirq stack
with the preempt-count set to 0, which could be deadly if we
try to take a softirq at that point, however we do so with
interrupts disabled, so I think we are ok.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently, we initialize the "current" pointer in the PACA (which
is used by the "current" macro in the kernel) before calling
setup_system(). That means that early_setup() is called with
current still "NULL" which is -not- a good idea. It happens to
work so far but breaks with lockdep when early code calls printk.
This changes it so that all PACAs are statically initialized with
__current pointing to the init task. For non-0 CPUs, this is fixed
up before use.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that we have the alpaca, the reg_save_ptr is no longer needed in the
paca. Eradicate all global uses of it and make it static in the iSeries
lpardata.c
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The iSeries HV only needs the first two fields of the paca statically
initialised, so create an alternate paca that contains only those and
switch to our real paca immediately after boot.
This is in order to make the 1024 cpu patches easier since they will no
longer have to statically initialise the pacas for iSeries.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
If an SLB miss interrupt happens while the RI bit of MSR is zero, we
can't just return, because RI being zero indicates that SRR0/SRR1
potentially had live values in them, and the process of taking an
interrupt overwrites them.
This should never happen, but if it does, we try to print a nice oops
message. That doesn't work, however, because the code at unrecov_slb
assumes that the MMU has been turned on, but we call it with the MMU
off (and have done so since the SLB miss handler was rewritten to run
without turning the MMU on) -- except on iSeries, where everything runs
with the MMU on.
This fixes it by adding the necessary code to turn the MMU on if
necessary.
Signed-off-by: Paul Mackerras <paulus@samba.org>
A couple of places are duplicating the function of
of_device_is_available; convert them to use it.
Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We have an assembly version of strncmp for the bootwrapper, but not
for the kernel, so we end up using the C version in the kernel. This
takes the strncmp code from the bootup and copies it to the kernel
proper, adding two instructions so it copes correctly with len==0.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Huang Ying
Nathan Lynch
Linus Torvalds
Srinivasa D S
Nathan Fontenot
Robert Jennings
Brian King
Segher Boessenkool
Luis Machado
Stephen Rothwell
Andrea Righi
Jason Wessel
Andi Kleen
Torez Smith
Benjamin Herrenschmidt
Arnd Bergmann
Mark Nelson
Ingo Molnar
Thomas Gleixner
Kumar Gala
Sonny Rao
Michael Neuling
Josh Boyer
Paul Gortmaker
Dave Kleikamp
Vitaly Bordug
John Linn
Michael Ellerman
Joel Schopp
Paul Mackerras
Jens Axboe
Abhishek Sagar
Emil Medve
Steven Rostedt
Jan Beulich
Roland McGrath
Al Viro
Nate Case
Huang Weiyi
Stefan Roese
Ulrich Drepper
Roman Zippel
Samuel Thibault
Christoph Lameter
Denis V. Lunev
Zhang Wei
Hollis Blanchard
Ishizaki Kou
Tony Breeds
Christoph Hellwig
Bjorn Helgaas
Andreas Schwab
Matthew Wilcox
Benjamin Herrenschmidt
Bartlomiej Zolnierkiewicz
Manish Ahuja
David Woodhouse
Roel Kluin