The vector extension introduces 32 128-bit vector registers and a set of
instruction to operate on the vector registers.
The kernel can control the use of vector registers for the problem state
program with a bit in control register 0. Once enabled for a process the
kernel needs to retain the content of the vector registers on context
switch. The signal frame is extended to include the vector registers.
Two new register sets NT_S390_VXRS_LOW and NT_S390_VXRS_HIGH are added
to the regset interface for the debugger and core dumps.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix calculation to decide if a 4-level kernel page table is required.
Git commit c972cc60c2 "s390/vmalloc: have separate modules area"
added the separate module area which reduces the size of the vmalloc
area but fails to take it into account for the 3 vs 4 level page table
decision.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The virtual-machine cpu information data block and the cpu-id of
the boot cpu can be used as source of device randomness.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We only have to check kdump memory for the MEM_GOING_OFFLINE action.
Therefore skip the test and return NOTIFY_OK for all other memory
hotplug actions.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently there are two s390 kernel dump config options "CONFIG_ZFCPDUMP"
and "CONFIG_CRASH_DUMP". In order to keep things simple and because the
"CONFIG_ZFCPDUMP" option already has a dependency to "CONFIG_CRASH_DUMP"
remove the CONFIG_ZFCPDUMP option.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use lowcore constant to improve the code generated for spinlocks.
[ Martin Schwidefsky: patch breakdown and code beautification ]
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The original bootmem allocator is getting replaced by memblock. To
cover the needs of the s390 kdump implementation the physical memory
list is used.
With this patch the bootmem allocator and its bitmaps are completely
removed from s390.
Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove another leftover from the time when we supported running
user space in either home or primary address space.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
There are only two uaccess variants on s390 left: the version that is used
if the mvcos instruction is available, and the page table walk variant.
So there is no need for expensive indirect function calls.
By default the mvcos variant will be called. If the mvcos instruction is not
available it will call the page table walk variant.
For minimal performance impact the "if (mvcos_is_available)" is implemented
with a jump label, which will be a six byte nop on machines with mvcos.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 updates from Martin Schwidefsky:
"The bulk of the s390 updates for v3.14.
New features are the perf support for the CPU-Measurement Sample
Facility and the EP11 support for the crypto cards. And the normal
cleanups and bug-fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (44 commits)
s390/cpum_sf: fix printk format warnings
s390: Fix misspellings using 'codespell' tool
s390/qdio: bridgeport support - CHSC part
s390: delete new instances of __cpuinit usage
s390/compat: fix PSW32_USER_BITS definition
s390/zcrypt: add support for EP11 coprocessor cards
s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
s390: use IS_ENABLED to check if a CONFIG is set to y or m
s390/cio: use device_lock to synchronize calls to the ccwgroup driver
s390/cio: use device_lock to synchronize calls to the ccw driver
s390/cio: fix unlocked access of online member
s390/cpum_sf: Add flag to process full SDBs only
s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function
s390/cpum_sf: Filter perf events based event->attr.exclude_* settings
s390/cpum_sf: Detect KVM guest samples
s390/cpum_sf: Add helper to read TOD from trailer entries
s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks
s390/cpum_sf: Dynamically extend the sampling buffer if overflows occur
s390/pci: reenable per default
s390/pci/dma: fix accounting of allocated_pages
...
Since under z/VM we cannot have more than 64 cpus, make sure the
cpu_possible_mask does not contain more bits.
This avoids wasting memory for dynamic per-cpu allocations if
CONFIG_NR_CPUS is larger than 64.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Simplify the uaccess code by removing the user_mode=home option.
The kernel will now always run in the home space mode.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Just add the new model number where appropiate.
Cc: stable@vger.kernel.org # v3.10
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The only user of saved_max_pfn in s390 is read_oldmem interface but we
have removed that interface, so saved_max_pfn is now unneeded in s390, and
we needn't set it anymore.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Simplify the memory detection code a bit by removing the CHUNK_OLDMEM
and CHUNK_CRASHK memory types.
They are not needed. Everything that is needed is a mechanism to
insert holes into the detected memory.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The current memory detection loop will detect all present memory of
a machine. This is true even if the user specified the "mem=" parameter
on the kernel command line.
This can be a problem since the memory detection may cause a fully
populated host page table for the guest, even for those parts of the
memory that the guest will never use afterwards.
So fix this and only detect memory up to a user supplied "mem=" limit
if specified.
Reported-by: Michael Johanssen <johanssn@de.ibm.com>
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When in kdump mode the kernel may access only the first couple of
megabytes for execution, the rest contains the dump. However
the size of the bitmap used by the bootmem allocator was calculated
for the whole amount of memory of the machine.
For very large machines this can lead to the situation that the kdump
kernel will not come up because not enough memory is available.
So fix this and calculate the size of the bitmap only for the piece
of memory that the kdump kernel actually uses.
Call reserve_oldmem() before setup_memory_end() so that the memory_chunk
array already has been updated with respect to oldmem chunks.
Afterwards setup_memory_end() will ignore those chunks.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The variable real_memory_size has odd semantics and has been used in
a broken way by e.g. the old kvm code.
Therefore get rid of it before anybody else makes use of it.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Use the 'ipldev' and 'condev' cio_ignore keywords to setup the
command line for zfcpdump.
Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Store the stack pointers in the lowcore for the kernel stack, the async
stack and the panic stack with the offset required for the first user.
This avoids an unnecessary add instruction on the system call path.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The size of the vmemmap must be a multiple of PAGES_PER_SECTION, since the
common code always initializes the vmemmap in such pieces.
So we must round up in order to not have a too small vmemmap.
Fixes an IPL crash on 31 bit with more than 1920MB.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Export pm_power_off symbol. Needed by at least one of the new device
drivers that come with CONFIG_PCI.
And all other architectures export that symbol as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow to generate code that only runs on zEC12 machines.
Also add a check which prevents the kernel to run on machines which
do not have any of the following new facilities installed:
- (48) decimal-floating-point zoned-conversion
- (49) execution-hint
- (49) load-and-trap
- (49) miscellaneous-instruction-extensions
- (49) processor-assist
- (50) constrained transactional-execution
- (73) transactional-execution
48, 49, 50 and 73 are the bit numbers of the facility indications for
each of the required facilities.
Note that we assume that user-space gets compiled with the same
compiler options, therefore we also test for a dfp facility even
if the kernel doesn't make use of it.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Move and rename init_storage_keys() to pageattr.c, so it can also be
used from the sclp memory hotplug code in order to initialize
storage keys.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add a special module area on top of the vmalloc area, which may be only
used for modules and bpf jit generated code.
This makes sure that inter module branches will always happen without a
trampoline and in addition having all the code within a 2GB frame is
branch prediction unit friendly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make use of the pfmf instruction, if available, to initialize storage keys
of whole 1MB or 2GB frames instead of initializing every single page with
the sske instruction.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since "Kconfig: split the s390 base menu" CONFIG_KEXEC gets always selected.
Therefore there is no point in keeping CONFIG_KEXEC anywhere.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Shorten the code for addressing mode initialization. Also add missing
__init annotations, since this code is only used during kernel initialization.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Renaming the globally visible variable "user_mode" to "addressing_mode" in
order to fix a name clash was not a good idea. (Commit 37fe1d73 "s390/mm:
rename user_mode variable to addressing_mode")
Looking at the code after a couple of weeks one thinks: addressing mode of
what?
So rename the variable again. This time to s390_user_mode. Which hopefully
makes more sense.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Change the default addressing mode so that user space runs in primary space
and the kernel runs in home space.
In addition remove the "switch_amode" kernel parameter so all users who
already specified they want the new default behaviour will stay in the
"switched" mode instead of in the opposite they intended.
If there is a need to switch addressing modes, this can be done with the
"user_mode" kernel parameter: user_mode=home
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow user-space processes to use transactional execution (TX).
If the TX facility is available user space programs can use
transactions for fine-grained serialization based on the data
objects that are referenced during a transaction. This is
useful for lockless data structures and speculative compiler
optimizations.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The bit for high gprs in the AT_HWCAP auxiliary vector field and the
highgprs tag in the output of /proc/cpuinfo should not be set for
31 bit kernels.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix name clash with user_mode() define which is also used in common code.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Merge tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Avi Kivity:
"Highlights include
- full big real mode emulation on pre-Westmere Intel hosts (can be
disabled with emulate_invalid_guest_state=0)
- relatively small ppc and s390 updates
- PCID/INVPCID support in guests
- EOI avoidance; 3.6 guests should perform better on 3.6 hosts on
interrupt intensive workloads)
- Lockless write faults during live migration
- EPT accessed/dirty bits support for new Intel processors"
Fix up conflicts in:
- Documentation/virtual/kvm/api.txt:
Stupid subchapter numbering, added next to each other.
- arch/powerpc/kvm/booke_interrupts.S:
PPC asm changes clashing with the KVM fixes
- arch/s390/include/asm/sigp.h, arch/s390/kvm/sigp.c:
Duplicated commits through the kvm tree and the s390 tree, with
subsequent edits in the KVM tree.
* tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits)
KVM: fix race with level interrupts
x86, hyper: fix build with !CONFIG_KVM_GUEST
Revert "apic: fix kvm build on UP without IOAPIC"
KVM guest: switch to apic_set_eoi_write, apic_write
apic: add apic_set_eoi_write for PV use
KVM: VMX: Implement PCID/INVPCID for guests with EPT
KVM: Add x86_hyper_kvm to complete detect_hypervisor_platform check
KVM: PPC: Critical interrupt emulation support
KVM: PPC: e500mc: Fix tlbilx emulation for 64-bit guests
KVM: PPC64: booke: Set interrupt computation mode for 64-bit host
KVM: PPC: bookehv: Add ESR flag to Data Storage Interrupt
KVM: PPC: bookehv64: Add support for std/ld emulation.
booke: Added crit/mc exception handler for e500v2
booke/bookehv: Add host crit-watchdog exception support
KVM: MMU: document mmu-lock and fast page fault
KVM: MMU: fix kvm_mmu_pagetable_walk tracepoint
KVM: MMU: trace fast page fault
KVM: MMU: fast path of handling guest page fault
KVM: MMU: introduce SPTE_MMU_WRITEABLE bit
KVM: MMU: fold tlb flush judgement into mmu_spte_update
...
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.
Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Setting the cpu restart parameters is done in three different fashions:
- directly setting the four parameters individually
- copying the four parameters with memcpy (using 4 * sizeof(long))
- copying the four parameters using a private structure
In addition code in entry*.S relies on a certain order of the restart
members of struct _lowcore.
Make all of this more robust to future changes by adding a
mem_absolute_assign(dest, val) define, which assigns val to dest
using absolute addressing mode. Also the load multiple instructions
in entry*.S have been split into separate load instruction so the
order of the struct _lowcore members doesn't matter anymore.
In addition move the prototypes of memcpy_real/absolute from uaccess.h
to processor.h. These memcpy* variants are not related to uaccess at all.
string.h doesn't seem to match as well, so lets use processor.h.
Also replace the eight byte array in struct _lowcore which represents a
misaliged u64 with a u64. The compiler will always create code that
handles the misaligned u64 correctly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For processing under KVM it is required to detect
the actual SCLP console type in order to set it as
preferred console.
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This patch introduces the new function memcpy_absolute() that allows to
copy memory using absolute addressing. This means that the prefix swap
does not apply when this function is used.
With this patch also all s390 kernel code that accesses absolute zero
now uses the new memcpy_absolute() function. The old and less generic
copy_to_absolute_zero() function is removed.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
In order to allow kdump based stand-alone dump, some information
has to be passed from the old kernel to the new dump kernel. This
is done via a the struct "os_info" that contains the following fields:
* crashkernel base and size
* reipl block
* vmcoreinfo
* init function
A pointer to os_info is stored at a well known storage location
and the whole structure as well as all fields are secured with
checksums.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Define struct pcpu and merge some of the NR_CPUS arrays into it, including
__cpu_logical_map, current_set and smp_cpu_state. Split smp related
functions to those operating on physical cpus and the functions operating
on a logical cpu number. Make the functions for physical cpus use a
pointer to a struct pcpu. This hides the knowledge about cpu addresses in
smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header.
The PSW restart mechanism is used to start secondary cpus, calling a
function on an online cpu, calling a function on the ipl cpu, and for
the nmi signal. Replace the different assembler functions with a
single function restart_int_handler. The new entry point calls a function
whose pointer is stored in the lowcore of the target cpu and it can wait
for the source cpu to stop. This covers all existing use cases.
Overall the code is now simpler and there are ~380 lines less code.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With gcc 4.6.0 we get a false compile warning:
arch/s390/kernel/setup.c: In function 'setup_arch':
arch/s390/kernel/setup.c:767:3: warning: 'msg' may be used
uninitialized in this function [-Wuninitialized]
arch/s390/kernel/setup.c:753:8: note: 'msg' was declared here
This patch makes gcc quiet.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.
This is the minimal patch which fixes the build issues.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits)
[S390] disassembler: mark exception causing instructions
[S390] Enable exception traces by default
[S390] return address of compat signals
[S390] sysctl: get rid of dead declaration
[S390] dasd: fix fixpoint divide exception in define_extent
[S390] dasd: add sanity check to detect path connection error
[S390] qdio: fix kernel panic for zfcp 31-bit
[S390] Add s390x description to Documentation/kdump/kdump.txt
[S390] Add VMCOREINFO_SYMBOL(high_memory) to vmcoreinfo
[S390] dasd: fix expiration handling for recovery requests
[S390] outstanding interrupts vs. smp_send_stop
[S390] ipc: call generic sys_ipc demultiplexer
[S390] zcrypt: Fix error return codes.
[S390] zcrypt: Rework length parameter checking.
[S390] cleanup trap handling
[S390] Remove Kerntypes leftovers
[S390] topology: increase poll frequency if change is anticipated
[S390] entry[64].S improvements
[S390] make arch/s390 subdirectories depend on config option
[S390] kvm: move cmf host id constant out of lowcore
...
Fix up conflicts in arch/s390/kernel/{smp.c,topology.c} due to the
sysdev removal clashing with "topology: get rid of ifdefs" which moved
some of that code around.
There is no reason for the cpu-measurement-facility host id constant to
reside in the lowcore where space is precious. Use an entry in the literal
pool in HANDLE_SIE_INTERCEPT and a stack slot in sie64a.
While we are at it replace the id -1 with 0 to indicate host execution.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The kernel address space of a 64 bit kernel currently uses a three level
page table and the vmemmap array has a fixed address and a fixed maximum
size. A three level page table is good enough for systems with less than
3.8TB of memory, for bigger systems four page table levels need to be
used. Each page table level costs a bit of performance, use 3 levels for
normal systems and 4 levels only for the really big systems.
To avoid bloating sparse.o too much set MAX_PHYSMEM_BITS to 46 for a
maximum of 64TB of memory.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>