"idle=nomwait" disables the use of the MWAIT
instruction from both C1 (C1_FFH) and deeper (C2C3_FFH)
C-states.
When MWAIT is unavailable, the BIOS and OS generally
negotiate to use the HALT instruction for C1,
and use IO accesses for deeper C-states.
This option is useful for power and performance
comparisons, and also to work around BIOS bugs
where broken MWAIT support is advertised.
http://bugzilla.kernel.org/show_bug.cgi?id=10807http://bugzilla.kernel.org/show_bug.cgi?id=10914
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
"idle=halt" limits the idle loop to using
the halt instruction. No MWAIT, no IO accesses,
no C-states deeper than C1.
If something is broken in the idle code,
"idle=halt" is a less severe workaround
than "idle=poll" which disables all power savings.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
* 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
generic-ipi: more merge fallout
generic-ipi: merge fix
x86, visws: use mach-default/entry_arch.h
x86, visws: fix generic-ipi build
generic-ipi: fixlet
generic-ipi: fix s390 build bug
generic-ipi: fix linux-next tree build failure
fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
fix "smp_call_function: get rid of the unused nonatomic/retry argument"
on_each_cpu(): kill unused 'retry' parameter
smp_call_function: get rid of the unused nonatomic/retry argument
sh: convert to generic helpers for IPI function calls
parisc: convert to generic helpers for IPI function calls
mips: convert to generic helpers for IPI function calls
m32r: convert to generic helpers for IPI function calls
arm: convert to generic helpers for IPI function calls
alpha: convert to generic helpers for IPI function calls
ia64: convert to generic helpers for IPI function calls
powerpc: convert to generic helpers for IPI function calls
...
Fix trivial conflicts due to rcu updates in kernel/rcupdate.c manually
The symbol account_system_vtime is used by the kvm module but
not exported. This breaks building with CONFIG_VIRT_CPU_ACCOUNTING
and CONFIG_KVM=m.
Signed-off-by: Doug Chapman <doug.chapman@hp.com>
Acked-by: Hidetosho Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
On a system where there are no hot pluggable cpus "additional_cpus"
is still set to -1 at the point where we call per_cpu_scan_finalize().
If we didn't find an SRAT table and so pick the default "32" for the
number of cpus, when we get to:
high_cpu = min(high_cpu + reserve_cpus, NR_CPUS);
we will end up initializing for just 31 cpus ... and so we will
die horribly when bringing up cpu#32.
Problem introduced by: 2c6e6db41f
"Minimize per_cpu reservations."
Acked-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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 ia64 to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
As noted by Akinobu Mita alloc_bootmem and related functions never return
NULL and always return a zeroed region of memory. Thus a NULL test or
memset after calls to these functions is unnecessary.
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The fix applied in e0c6d97c65
"security hole in sn2_ptc_proc_write" didn't take into account
the case where count==0 (which results in a buffer underrun
when adding the trailing '\0'). Thanks to Andi Kleen for
pointing this out.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Call check_sal_cache_flush() after platform_setup() as
check_sal_cache_flush() now relies on being able to call platform
vector code.
Problem was introduced by: 3463a93def
"Update check_sal_cache_flush to use platform_send_ipi()"
Signed-off-by: Jes Sorensen <jes@sgi.com>
Tested-by: Alex Chiang: <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Security hole in sn2_ptc_proc_write
It is possible to overrun a buffer with a write to this /proc file.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Fix build error in CONFIG_IA64_SGI_UV config. (GENERIC builds
are ok).
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
check_sal_cache_flush is used to detect broken firmware that drops
pending interrupts.
The old implementation schedules a timer interrupt for itself in
the future by getting the current value of the Interval Timer
Counter + 1000 cycles, waits for the interrupt to be pended, calls
SAL_CACHE_FLUSH, and finally checks to see if the interrupt is
still pending.
This implementation can cause problems for virtual machine code if
the process of scheduling the timer interrupt takes more than 1000
cycles; the virtual machine can end up sleeping for several hundred
years while waiting for the ITC to wrap around.
The fix is to use platform_send_ipi. The processor will still send
an interrupt to itself, using the IA64_IPI_DM_INT delivery mode,
which causes the IPI to look like an external interrupt. The rest
of the SAL_CACHE_FLUSH + checking to see if the interrupt is still
pending remains unchanged.
This fix has been boot tested successfully on:
- intel tiger2
- hp rx6600
- hp rx5670
The rx5670 has known buggy firmware, where SAL_CACHE_FLUSH drops
pending interrupts. A boot test on this machine showed this message
on the console:
SAL: SAL_CACHE_FLUSH drops interrupts; PAL_CACHE_FLUSH will be used instead
Which proves that the self-inflicted IPI approach is viable. And
as expected, the other tested platforms correctly did not display
the warning.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This is a SLIT sanity checking patch. It moves slit_valid() function to
generic ACPI code and does sanity checking for both x86 and ia64. It sets up
node_distance with LOCAL_DISTANCE and REMOTE_DISTANCE when hitting invalid
SLIT table on ia64. It also cleans up unused variable localities in
acpi_parse_slit() on x86.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Move the cleanup of the async queue to the close callback from the flush
callback. This avoids losing asynchronous overflow notifications when
the file descriptor is shared by multiple processes and one terminates.
Signed-off-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Only copy in the data actually requested by the instruction emulation
and zero pad the destination register first. This avoids the problem
where emulated mmio access got garbled data from ld2.acq instructions
in the vga console driver.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Problem: An application violating the architectural rules regarding
operation dependencies and having specific Register Stack Engine (RSE)
state at the time of the violation, may result in an illegal operation
fault and invalid RSE state. Such faults may initiate a cascade of
repeated illegal operation faults within OS interruption handlers.
The specific behavior is OS dependent.
Implication: An application causing an illegal operation fault with
specific RSE state may result in a series of illegal operation faults
and an eventual OS stack overflow condition.
Workaround: OS interruption handlers that switch to kernel backing
store implement a check for invalid RSE state to avoid the series
of illegal operation faults.
The core of the workaround is the RSE_WORKAROUND code sequence
inserted into each invocation of the SAVE_MIN_WITH_COVER and
SAVE_MIN_WITH_COVER_R19 macros. This sequence includes hard-coded
constants that depend on the number of stacked physical registers
being 96. The rest of this patch consists of code to disable this
workaround should this not be the case (with the presumption that
if a future Itanium processor increases the number of registers, it
would also remove the need for this patch).
Move the start of the RBS up to a mod32 boundary to avoid some
corner cases.
The dispatch_illegal_op_fault code outgrew the spot it was
squatting in when built with this patch and CONFIG_VIRT_CPU_ACCOUNTING=y
Move it out to the end of the ivt.
Signed-off-by: Tony Luck <tony.luck@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] return to old errno choice in mkdir() et.al.
[Patch] fs/binfmt_elf.c: fix wrong return values
[PATCH] get rid of leak in compat_execve()
[Patch] fs/binfmt_elf.c: fix a wrong free
[PATCH] avoid multiplication overflows and signedness issues for max_fds
[PATCH] dup_fd() part 4 - race fix
[PATCH] dup_fd() - part 3
[PATCH] dup_fd() part 2
[PATCH] dup_fd() fixes, part 1
[PATCH] take init_files to fs/file.c
Move rcu-protected lists from list.h into a new header file rculist.h.
This is done because list are a very used primitive structure all over the
kernel and it's currently impossible to include other header files in this
list.h without creating some circular dependencies.
For example, list.h implements rcu-protected list and uses rcu_dereference()
without including rcupdate.h. It actually compiles because users of
rcu_dereference() are macros. Others RCU functions could be used too but
aren't probably because of this.
Therefore this patch creates rculist.h which includes rcupdates without to
many changes/troubles.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Josh Triplett <josh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The GVMM module is position independent since it is relocated to the guest
address space.
Commit ea696f9cf ("ia64 kvm fixes for O=... builds") broke this by linking
GVMM with non-PIC objects.
Fix by creating two files: memset.S and memcpy.S which just include the files
under arch/ia64/lib/{memset.S, memcpy.S} respectively.
[akpm: don't delete files which we need]
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The patch aims to fix a performance issue for the syscall
personality(PER_LINUX32).
On IA-64 box, the syscall personality (PER_LINUX32) has poor performance
because it failed to find the Linux/x86 execution domain. Then it tried
to load the kernel module however it failed always and it used the default
execution domain PER_LINUX instead. Requesting kernel modules is very
expensive. It caused the performance issue. (see the function
lookup_exec_domain in kernel/exec_domain.c).
To resolve the issue, execution domain Linux/x86 is always registered in
initialization time for IA-64 architecture.
Signed-off-by: Xiaolan Huang <xiaolan.huang@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
acpi_unregister_gsi() should "undo" what acpi_register_gsi() does.
On systems that have legacy interrupts, acpi_unregister_gsi erroneously calls
iosapci_unregister_intr() which is wrong to do and causes a loud warning.
acpi_unregister_gsi() should just return in these cases.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
There is only palinfo_handle_smp as (indirect) user of palinfo_smp_call (by
way of smp_call_function_single) and surely palinfo_handle_smp never pass
NULL as parameter for info.
Signed-off-by: Simon Holm Thøgersen <odie@cs.aau.dk>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Fix a typo, and coding style cleanups for pfm_handle_work().
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch does:
- make comment at next to resched check more robust
- move "re-check" comments to next to where change predicate regs
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
[Bug-fix for "[BUG?][2.6.25-mm1] sleeping during IRQ disabled"]
This patch does:
- enable interrupts before calling schedule() as same as others, ex. x86
- enable interrupts during ia64_do_signal() and ia64_sync_krbs()
- do_notify_resume_user() is still called with interrupts disabled, since
we can take short path of fsys_mode if-statement quickly.
- pfm_handle_work() is also called with interrupts disabled, since
it can deal interrupt mask within itself.
- fix/add some comments/notes
Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The sequence executed in check_sal_cache_flush:
- pend a timer interrupt
- call SAL_CACHE_FLUSH
- see if interrupt is still pending
can hang HP machines with buggy SAL_CACHE_FLUSH implementations.
Provide a kernel command-line argument to allow users skip this
check if desired. Using this parameter will force ia64_sal_cache_flush
to call ia64_pal_cache_flush() instead of SAL_CACHE_FLUSH.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Some IA64 machines map all cell-local memory above 4 GB (32 bit limit).
However, in most cases, the kernel needs some memory below that limit that is
DMA-capable. So in this machine configuration, the crashkernel will be reserved
above 4 GB.
For machines that use SWIOTLB implementation because they lack an I/O MMU
the low memory is required by the SWIOTLB implementation. In that case,
it doesn't make sense to reserve the crashkernel at all because it's unusable
for kdump.
A special case is the "hpzx1" machine vector. In theory, it has a I/O MMU, so
it can be booted above 4 GB. However, in the kdump case that is not possible
because of changeset 51b58e3e26ebfb8cd56825c4b396ed251f51dec9:
On HP zx1 machines, the 'machvec=dig' parameter is needed for the kdump
kernel to avoid problems with the HP sba iommu. The problem is that during
the boot of the kdump kernel, the iommu is re-initialized, so in-flight DMA
from improperly shutdown drivers causes an IOTLB miss which leads to an
MCA. With kdump, the idea is to get into the kdump kernel with as little
code as we can, so shutting down drivers properly is not an option.
The workaround is to add 'machvec=dig' to the kdump kernel boot parameters.
This makes the kdump kernel avoid using the sba iommu altogether, leaving
the IOTLB intact. Any ongoing DMA falls harmlessly outside the kdump
kernel. After the kdump kernel reboots, all devices will have been
shutdown properly and DMA stopped.
This patch pushes that functionality into the sba iommu initialization
code, so that users won't have to find the obscure documentation telling
them about 'machvec=dig'.
This means that also for hpzx1 it's not possible to boot when all
memory is above the 4 GB limit. So the only machine vectors that can handle
this case are "sn2" and "uv".
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch adds the basic IA64 machvec infrastructure to support
the SGI "UV" platform.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Races galore... General rule: as soon as it's in descriptor table,
it's over; another thread might have started IO on it/dup2() it
elsewhere/dup2() something *over* it/etc. fd_install() is the very
last step one should take - it's a point of no return.
Besides, the damn thing leaked on failure exits...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Replace TIF_RESTORE_SIGMASK with TS_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: Tony Luck <tony.luck@intel.com>
Fix indenting of switch statement to follow CodingStyle, and
pull out handling of call_data into an inlined function.
I confirmed that applying this fix doesn't affect assembled code.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Rename div64_64 to div64_u64 to make it consistent with the other divide
functions, so it clearly includes the type of the divide. Move its definition
to math64.h as currently no architecture overrides the generic implementation.
They can still override it of course, but the duplicated declarations are
avoided.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch silences:
WARNING: vmlinux.o(.text+0x44672): Section mismatch in
reference from the function arch_register_cpu() to the
function .cpuinit.text:register_cpu()
Changes are based on codes in arch/x86/kernel/topology.c
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch removes following warning:
WARNING: vmlinux.o(.exit.text+0xb1): Section mismatch in
reference from the function palinfo_exit() to the variable
.cpuinit.data:palinfo_cpu_notifier
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch shuts up the following:
WARNING: vmlinux.o(.text+0x7102): Section mismatch in
reference from the function fixup_irqs() to the function
.devinit.text:ia64_disable_timer()
Removing ia64_disable_timer() is safe because there are no functions
calling it other than the fixup_irqs(),
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch kills:
WARNING: vmlinux.o(.text+0x1702): Section mismatch in
reference from the function acpi_register_ioapic() to the
function .devinit.text:iosapic_init()
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
- Operations are now a shared const function block as with most other Linux
objects
- Introduce wrappers for some optional functions to get consistent behaviour
- Wrap put_char which used to be patched by the tty layer
- Document which functions are needed/optional
- Make put_char report success/fail
- Cache the driver->ops pointer in the tty as tty->ops
- Remove various surplus lock calls we no longer need
- Remove proc_write method as noted by Alexey Dobriyan
- Introduce some missing sanity checks where certain driver/ldisc
combinations would oops as they didn't check needed methods were present
[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
TIF_RESTORE_SIGMASK no longer needs to be in the _TIF_WORK_* masks.
Those low bits are scarce. Renumber TIF_RESTORE_SIGMASK to free one up.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Legacy HP ia64 platforms currently cannot provide
/proc/cpuinfo/physical_id due to legacy SAL/PAL implementations.
However, that physical topology information can be obtained
via ACPI.
Provide an interface that gives ACPI one last chance to provide
physical_id for these legacy platforms. This logic only comes
into play iff:
- ACPI actually provides slot information for the CPU
- we lack a valid socket_id
Otherwise, we don't do anything.
Since x86 uses the ACPI processor driver as well, we provide a nop
stub function for arch_fix_phys_package_id() in asm-x86/topology.h
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Zhao Yakui
Linus Torvalds
Ingo Molnar
Doug Chapman
Tony Luck
Jens Axboe
Julia Lawall
Cliff Wickman
Jes Sorensen
Jack Steiner
Alex Chiang
Fenghua Yu
stephane eranian
Franck Bui-Huu
Xiantao Zhang
Al Viro
Huang, Xiaolan
Prarit Bhargava
Simon Holm Thøgersen
Hidetoshi Seto
Bernhard Walle
Al Viro
Roland McGrath
Roman Zippel
Alan Cox
akpm@linux-foundation.org