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57120 commits

Author SHA1 Message Date
Fenghua Yu
101068c1f4 x86, mem: memcpy_64.S: Optimize memcpy by enhanced REP MOVSB/STOSB
Support memcpy() with enhanced rep movsb. On processors supporting enhanced
rep movsb, the alternative memcpy() function using enhanced rep movsb overrides the original function and the fast string
function.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-8-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:29 -07:00
Fenghua Yu
4307bec934 x86, mem: copy_user_64.S: Support copy_to/from_user by enhanced REP MOVSB/STOSB
Support copy_to_user/copy_from_user() by enhanced REP MOVSB/STOSB.
On processors supporting enhanced REP MOVSB/STOSB, the alternative
copy_user_enhanced_fast_string function using enhanced rep movsb overrides the
original function and the fast string function.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-7-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:28 -07:00
Fenghua Yu
e365c9df2f x86, mem: clear_page_64.S: Support clear_page() with enhanced REP MOVSB/STOSB
Intel processors are adding enhancements to REP MOVSB/STOSB and the use of
REP MOVSB/STOSB for optimal memcpy/memset or similar functions is recommended.
Enhancement availability is indicated by CPUID.7.0.EBX[9] (Enhanced REP MOVSB/
STOSB).

Support clear_page() with rep stosb for processor supporting enhanced REP MOVSB
/STOSB. On processors supporting enhanced REP MOVSB/STOSB, the alternative
clear_page_c_e function using enhanced REP STOSB overrides the original function
and the fast string function.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-6-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:27 -07:00
Fenghua Yu
9072d11da1 x86, alternative: Add altinstruction_entry macro
Add altinstruction_entry macro to generate .altinstructions section
entries from assembly code.  This should be less failure-prone than
open-coding.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-5-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:25 -07:00
Fenghua Yu
5097313363 x86, alternative, doc: Add comment for applying alternatives order
Some string operation functions may be patched twice, e.g. on enhanced REP MOVSB
/STOSB processors, memcpy is patched first by fast string alternative function,
then it is patched by enhanced REP MOVSB/STOSB alternative function.

Add comment for applying alternatives order to warn people who may change the
applying alternatives order for any reason.

[ Documentation-only patch ]

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-4-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:25 -07:00
Fenghua Yu
161ec53c70 x86, mem, intel: Initialize Enhanced REP MOVSB/STOSB
If kernel intends to use enhanced REP MOVSB/STOSB, it must ensure
IA32_MISC_ENABLE.Fast_String_Enable (bit 0) is set and CPUID.(EAX=07H, ECX=0H):
EBX[bit 9] also reports 1.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-3-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 15:40:23 -07:00
Fenghua Yu
724a92ee45 x86, cpufeature: Add CPU feature bit for enhanced REP MOVSB/STOSB
Intel processors are adding enhancements to REP MOVSB/STOSB and the use of
REP MOVSB/STOSB for optimal memcpy/memset or similar functions is recommended.
Enhancement availability is indicated by CPUID.7.0.EBX[9] (Enhanced REP MOVSB/
STOSB).

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305671358-14478-2-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-17 14:56:36 -07:00
Fenghua Yu
2494b030ba x86, cpufeature: Fix cpuid leaf 7 feature detection
CPUID leaf 7, subleaf 0 returns the maximum subleaf in EAX, not the
number of subleaves.  Since so far only subleaf 0 is defined (and only
the EBX bitfield) we do not need to qualify the test.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1305660806-17519-1-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@kernel.org> 2.6.36..39
2011-05-17 13:36:29 -07:00
Peter Zijlstra
63b6a6758e perf events, x86: Fix Intel Nehalem and Westmere last level cache event definitions
The Intel Nehalem offcore bits implemented in:

  e994d7d23a: perf: Fix LLC-* events on Intel Nehalem/Westmere

... are wrong: they implemented _ACCESS as _HIT and counted OTHER_CORE_HIT* as
MISS even though its clearly documented as an L3 hit ...

Fix them and the Westmere definitions as well.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1299119690-13991-3-git-send-email-ming.m.lin@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-06 11:24:48 +02:00
Frederic Weisbecker
925f83c085 hw_breakpoints, powerpc: Fix CONFIG_HAVE_HW_BREAKPOINT off-case in ptrace_set_debugreg()
We make use of ptrace_get_breakpoints() / ptrace_put_breakpoints() to
protect ptrace_set_debugreg() even if CONFIG_HAVE_HW_BREAKPOINT if off.
However in this case, these APIs are not implemented.

To fix this, push the protection down inside the relevant ifdef.
Best would be to export the code inside
CONFIG_HAVE_HW_BREAKPOINT into a standalone function to cleanup
the ifdefury there and call the breakpoint ref API inside. But
as it is more invasive, this should be rather made in an -rc1.

Fixes this build error:

  arch/powerpc/kernel/ptrace.c:1594: error: implicit declaration of function 'ptrace_get_breakpoints' make[2]: ***

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LPPC <linuxppc-dev@lists.ozlabs.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: v2.6.33.. <stable@kernel.org>
Link: http://lkml.kernel.org/r/1304639598-4707-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-06 11:24:46 +02:00
Ingo Molnar
4d70230bb4 Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into perf/urgent 2011-05-06 08:11:28 +02:00
Linus Torvalds
bfd412db9e Merge branch 'for-linus' of git://github.com/at91linux/linux-2.6-at91
* 'for-linus' of git://github.com/at91linux/linux-2.6-at91:
  at91: Add ARCH_ID and basic cpu macros definition for 5series chips family.
  arm: at91: fix compiler warning for eb01 board build
  arm: at91: minimal defconfig for at91x40 SoC
  ARM: at91: AT91CAP9 has a macb device
2011-05-05 21:27:57 -07:00
Ingo Molnar
98bb318864 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2011-05-04 20:33:42 +02:00
Linus Torvalds
609cfda586 Merge branch 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
  xen/mmu: Add workaround "x86-64, mm: Put early page table high"
2011-05-03 09:25:42 -07:00
Linus Torvalds
bab0dcc717 Merge branches 'x86-fixes-for-linus' and 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, reboot: Fix relocations in reboot_32.S
  x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
  x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors

* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Fix typo CONFIG_GENIRC_IRQ_SHOW_LEVEL
2011-05-03 09:23:44 -07:00
Linus Torvalds
5933f2ae35 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
  sysctl: net: call unregister_net_sysctl_table where needed
  Revert: veth: remove unneeded ifname code from veth_newlink()
  smsc95xx: fix reset check
  tg3: Fix failure to enable WoL by default when possible
  networking: inappropriate ioctl operation should return ENOTTY
  amd8111e: trivial typo spelling: Negotitate -> Negotiate
  ipv4: don't spam dmesg with "Using LC-trie" messages
  af_unix: Only allow recv on connected seqpacket sockets.
  mii: add support of pause frames in mii_get_an
  net: ftmac100: fix scheduling while atomic during PHY link status change
  usbnet: Transfer of maintainership
  usbnet: add support for some Huawei modems with cdc-ether ports
  bnx2: cancel timer on device removal
  iwl4965: fix "Received BA when not expected"
  iwlagn: fix "Received BA when not expected"
  dsa/mv88e6131: fix unknown multicast/broadcast forwarding on mv88e6085
  usbnet: Resubmit interrupt URB if device is open
  iwl4965: fix "TX Power requested while scanning"
  iwlegacy: led stay solid on when no traffic
  b43: trivial: update module info about ucode16_mimo firmware
  ...
2011-05-02 18:00:43 -07:00
H. Peter Anvin
7806a49ab6 x86, reboot: Fix relocations in reboot_32.S
The use of base for %ebx in this file is arbitrary, *except* that we
also use it to compute the real-mode segment.  Therefore, make it so
that r_base really is the true address to which %ebx points.

This resolves kernel bugzilla 33302.

Reported-and-tested-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-08os5wi3yq1no0y4i5m4z7he@git.kernel.org
2011-05-02 14:44:46 -07:00
Stefano Stabellini
b9269dc7bf xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
mask_rw_pte is currently checking if a pfn is a pagetable page if it
falls in the range pgt_buf_start - pgt_buf_end but that is incorrect
because pgt_buf_end is a moving target: pgt_buf_top is the real
boundary.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:52 -04:00
Konrad Rzeszutek Wilk
a38647837a xen/mmu: Add workaround "x86-64, mm: Put early page table high"
As a consequence of the commit:

commit 4b239f458c
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Fri Dec 17 16:58:28 2010 -0800

    x86-64, mm: Put early page table high

it causes the Linux kernel to crash under Xen:

mapping kernel into physical memory
Xen: setup ISA identity maps
about to get started...
(XEN) mm.c:2466:d0 Bad type (saw 7400000000000001 != exp 1000000000000000) for mfn b1d89 (pfn bacf7)
(XEN) mm.c:3027:d0 Error while pinning mfn b1d89
(XEN) traps.c:481:d0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
...

The reason is that at some point init_memory_mapping is going to reach
the pagetable pages area and map those pages too (mapping them as normal
memory that falls in the range of addresses passed to init_memory_mapping
as argument). Some of those pages are already pagetable pages (they are
in the range pgt_buf_start-pgt_buf_end) therefore they are going to be
mapped RO and everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW.  When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).

In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).

For this reason, this function is introduced which is called _after_
the init_memory_mapping has completed (in a perfect world we would
call this function from init_memory_mapping, but lets ignore that).

Because we are called _after_ init_memory_mapping the pgt_buf_[start,
end,top] have all changed to new values (b/c another init_memory_mapping
is called). Hence, the first time we enter this function, we save
away the pgt_buf_start value and update the pgt_buf_[end,top].

When we detect that the "old" pgt_buf_start through pgt_buf_end
PFNs have been reserved (so memblock_x86_reserve_range has been called),
we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top.

And then we update those "old" pgt_buf_[end|top] with the new ones
so that we can redo this on the next pagetable.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Updated with Jeremy's comments]
[v2: Added the crash output]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:34 -04:00
Linus Torvalds
625a3b6057 Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm: (47 commits)
  CLKDEV: Fix clkdev return value for NULL clk case
  ARM: 6891/1: prevent heap corruption in OABI semtimedop
  ARM: kprobes: Tidy-up kprobes-decode.c
  ARM: kprobes: Add emulation of hint instructions like NOP and WFI
  ARM: kprobes: Add emulation of SBFX, UBFX, BFI and BFC instructions
  ARM: kprobes: Add emulation of MOVW and MOVT instructions
  ARM: kprobes: Reject probing of undefined data processing instructions
  ARM: kprobes: Remove redundant code in space_1111
  ARM: kprobes: Fix emulation of PLD instructions
  ARM: kprobes: Reject probing of SETEND instructions
  ARM: kprobes: Consolidate stub decoding functions
  ARM: kprobes: Reject probing of all coprocessor instructions
  ARM: kprobes: Fix emulation of USAD8 instructions
  ARM: kprobes: Fix emulation of SMUAD, SMUSD and SMMUL instructions
  ARM: kprobes: Fix emulation of SXTB16, SXTB, SXTH, UXTB16, UXTB and UXTH instructions
  ARM: kprobes: Reject probing of undefined media instructions
  ARM: kprobes: Add emulation of RBIT instruction
  ARM: kprobes: Reject probing of LDRB instructions which load PC
  ARM: kprobes: Fix emulation of LDRD and STRD instructions
  ARM: kprobes: Reject probing of LDR/STR instructions which update PC unpredictably
  ...
2011-05-02 12:17:05 -07:00
Linus Torvalds
96f3ee2805 Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] irqstats: fix counting of pfault, dasd diag and virtio irqs
  [S390] prng: fix pointer arithmetic
2011-05-02 08:47:35 -07:00
Yinghai Lu
2be19102b7 x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
numa_cleanup_meminfo() trims each memblk between low (0) and
high (max_pfn) limits and discards empty ones.  However, the
emptiness detection incorrectly used equality test.  If the
start of a memblk is higher than max_pfn, it is empty but fails
the equality test and doesn't get discarded.

The condition triggers when max_pfn is lower than start of a
NUMA node and results in memory misconfiguration - leading to
WARN_ON()s and other funnies.  The bug was discovered in devel
branch where 32bit too uses this code path for NUMA init.  If a
node is above the addressing limit, max_pfn ends up lower than
the node triggering this problem.

The failure hasn't been observed on x86-64 but is still possible
with broken hardware e820/NUMA info.  As the fix is very low
risk, it would be better to apply it even for 64bit.

Fix it by using >= instead of ==.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Extracted the actual fix from the original patch and rewrote patch description. ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110501171204.GO29280@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 19:15:11 +02:00
Boris Ostrovsky
e20a2d205c x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors
Older AMD K8 processors (Revisions A-E) are affected by erratum
400 (APIC timer interrupts don't occur in C states greater than
C1). This, for example, means that X86_FEATURE_ARAT flag should
not be set for these parts.

This addresses regression introduced by commit
b87cf80af3 ("x86, AMD: Set ARAT
feature on AMD processors") where the system may become
unresponsive until external interrupt (such as keyboard input)
occurs. This results, for example, in time not being reported
correctly, lack of progress on the system and other lockups.

Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1304113663-6586-1-git-send-email-ostr@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 18:55:51 +02:00
Linus Torvalds
40a963502c Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86, nmi: Move LVT un-masking into irq handlers
  perf events, x86: Work around the Nehalem AAJ80 erratum
  perf, x86: Fix BTS condition
  ftrace: Build without frame pointers on Microblaze
2011-04-29 15:08:53 -07:00
Linus Torvalds
a6ab948e65 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: ce4100: Configure IOAPIC pins for USB and SATA to level type
  x86: devicetree: Configure IOAPIC pin only once
  x86, setup: When probing memory with e801, use ax/bx as a pair
2011-04-29 15:07:19 -07:00
Linus Torvalds
9748d4d2b4 Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  OMAP3+: voltage: remove initial voltage
  OMAP4: Intialize IVA Device in addition to DSP device.
  omap: rx51: mark reserved memory earlier
  OMAP3: l3: fix for "irq 10: nobody cared" message
  arm: omap2: enable smc instruction for sleep34xx
  OMAP2/3: hwmod: fix gpio-reset timeouts seen during bootup.
  OMAP3: PM: Do not rely on ROM code to restore CM_AUTOIDLE_PLL.AUTO_PERIPH_DPLL
  OMAP2+: PM: Fix the saving of CM_AUTOIDLE_PLL register on scratchpad area
  OMAP4: clock data: Change DSS clock aliases
  OMAP2+: hwmod data: Fix wrong dma_system end address
2011-04-29 07:54:48 -07:00
Dan Rosenberg
0f22072ab5 ARM: 6891/1: prevent heap corruption in OABI semtimedop
When CONFIG_OABI_COMPAT is set, the wrapper for semtimedop does not
bound the nsops argument.  A sufficiently large value will cause an
integer overflow in allocation size, followed by copying too much data
into the allocated buffer.  Fix this by restricting nsops to SEMOPM.
Untested.

Cc: stable@kernel.org
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-04-29 15:53:14 +01:00
Russell King
408133e9dc Merge branch 'kprobes' of git://git.linaro.org/people/nico/linux into fixes 2011-04-29 11:02:45 +01:00
Heiko Carstens
a985183285 [S390] irqstats: fix counting of pfault, dasd diag and virtio irqs
pfault, dasd diag and virtio all use the same external interrupt number.
The respective interrupt handlers decide by the subcode if they are
meant to handle the interrupt.
Counting is currently done before looking at the subcode which means
each handler counts an interrupt even if it is not handling it.
Fix this by moving the kstat code after the code which looks at the
subcode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-04-29 10:42:25 +02:00
Jon Medhurst
cdc2536115 ARM: kprobes: Tidy-up kprobes-decode.c
- Remove coding standard violations reported by checkpatch.pl
- Delete comment about handling of conditional branches which is no
  longer true.
- Delete comment at end of file which lists all ARM instructions. This
  duplicates data available in the ARM ARM and seems like an
  unnecessary maintenance burden to keep this up to date and accurate.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
9425493078 ARM: kprobes: Add emulation of hint instructions like NOP and WFI
Being able to probe NOP instructions is useful for hard-coding probeable
locations and is used by the kprobes test code.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:01 -04:00
Jon Medhurst
20e8155e24 ARM: kprobes: Add emulation of SBFX, UBFX, BFI and BFC instructions
These bit field manipulation instructions occur several thousand
times in an ARMv7 kernel.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:41:00 -04:00
Jon Medhurst
c9836777d5 ARM: kprobes: Add emulation of MOVW and MOVT instructions
The MOVW and MOVT instructions account for approximately 7% of all
instructions in a ARMv7 kernel as GCC uses them instead of a literal
pool.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f704a6e25b ARM: kprobes: Reject probing of undefined data processing instructions
The instruction decoding in space_cccc_000x needs to reject probing of
instructions with undefined patterns as they may in future become
defined and then emulated faultily - as has already happened with the
SMC instruction.

This fix is achieved by testing for the instruction patterns we want to
probe and making the the default fall-through paths reject probes. This
also allows us to remove some explicit tests for instructions that we
wish to reject, as that is now the default action.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
72c2bab2be ARM: kprobes: Remove redundant code in space_1111
The tests to explicitly reject probing CPS, RFE and SRS instructions
are redundant as the default case is now to reject undecoded patterns.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
41713d1396 ARM: kprobes: Fix emulation of PLD instructions
The PLD instructions wasn't being decoded correctly and the emulation
code wasn't adjusting PC correctly.

As the PLD instruction is only a performance hint we emulate it as a
simple nop, and we can broaden the instruction decoding to take into
account newer PLI and PLDW instructions.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
f0aeb8bff0 ARM: kprobes: Reject probing of SETEND instructions
The emulation of SETEND was broken as it changed the endianess for
the running kprobes handling code. Rather than adding a new simulation
routine to fix this we'll just reject probing of SETEND as these should
be very rare in the kernel.

Note, the function emulate_none is now unused but it is left in the
source code as future patches will use it.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
ac211c6994 ARM: kprobes: Consolidate stub decoding functions
Following the change to remove support for coprocessor instructions
we are left with three stub functions which can be consolidated.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:59 -04:00
Jon Medhurst
fa1a03b429 ARM: kprobes: Reject probing of all coprocessor instructions
The kernel doesn't currently support VFP or Neon code, and probing of
code with CP15 operations is fraught with bad consequences. Therefore we
don't need the ability to probe coprocessor instructions and the code to
support this can be removed.

The removed code also had at least two bugs:
 - MRC into R15 should set CPSR not trash PC
 - LDC and STC which use PC as base register needed the address offset by 8

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
c6e4ae3291 ARM: kprobes: Fix emulation of USAD8 instructions
The USAD8 instruction wasn't being explicitly decoded leading
to the incorrect emulation routine being called. It can be correctly
decoded in the same way as the signed multiply instructions so we move
the decoding there.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
038c3839c9 ARM: kprobes: Fix emulation of SMUAD, SMUSD and SMMUL instructions
The signed multiply instructions were being decoded incorrectly.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
8dd7cfbed8 ARM: kprobes: Fix emulation of SXTB16, SXTB, SXTH, UXTB16, UXTB and UXTH instructions
These sign extension instructions are encoded as extend-and-add
instructions where the register to add is specified as r15. The decoding
routines weren't checking for this and were using the incorrect
emulation code, giving incorrect results.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
780b5c1162 ARM: kprobes: Reject probing of undefined media instructions
The instructions space for media instructions contains some undefined
patterns. We need to reject probing of these because they may in future
become defined and the kprobes code may then emulate them faultily.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:58 -04:00
Jon Medhurst
0e384ed164 ARM: kprobes: Add emulation of RBIT instruction
The v6T2 RBIT instruction was accidentally being emulated correctly,
this patch adds correct decoding for the instruction.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
81ff5720b9 ARM: kprobes: Reject probing of LDRB instructions which load PC
These instructions are specified as UNPREDICTABLE.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
5c6b76fc7d ARM: kprobes: Fix emulation of LDRD and STRD instructions
The decoding of these instructions got the register indexed and
immediate indexed forms the wrong way around, causing incorrect
emulation.

Instructions like "LDRD Rx, [Rx]" were corrupting Rx because the base
register writeback was being performed unconditionally, overwriting the
value just loaded from memory. The fix is to only writeback the base
register when that form of the instruction is used. Note, now that we
reject probing writeback with PC the emulation code doesn't need the
check rn!=15.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
54823accfc ARM: kprobes: Reject probing of LDR/STR instructions which update PC unpredictably
Using PC as an base register with writeback is UNPREDICTABLE, as is non
word-sized loads or stores of PC. (We only really care about preventing
loads to PC but it keeps the code simpler if we also exclude stores.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:57 -04:00
Jon Medhurst
6823fc85fc ARM: kprobes: Fix emulation of LDRH, STRH, LDRSB and LDRSH instructions
The decoding of these instructions got the register indexed and
immediate indexed forms the wrong way around, causing incorrect
emulation.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
ec58d7f237 ARM: kprobes: Reject probing of STREX and LDREX instructions
The emulation code for STREX and LDREX instructions is faulty, however,
rather than attempting to fix this we reject probes of these
instructions. We do this because they can never succeed in gaining
exclusive access as the exception framework clears the exclusivity
monitor when a probes breakpoint is hit. (This is a general problem
when probing all instructions executing between a LDREX and its
corresponding STREX and can lead to infinite retry loops.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00
Jon Medhurst
ba48d40713 ARM: kprobes: Reject probing of undefined multiply instructions
The instructions space for 'Multiply and multiply-accumulate'
instructions contains some undefined patterns. We need to reject
probing of these because they may in future become defined and the
kprobes code may then emulate them faultily.

This has already happened with the new MLS instruction which this patch
also adds correct decoding for as well as tightening up other decoding
tests. (Before this patch the wrong emulation routine was being called
for MLS though it still produced correct results.)

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28 23:40:56 -04:00