linux-toradex.git/arch/x86/kernel/alternative.c, branch v3.4.76 Linux kernel for Apalis and Colibri modules x86/alternatives: Fix p6 nops on non-modular kernels 2012-10-07T15:32:29+00:00 Avi Kivity avi@redhat.com 2012-08-22T10:03:48+00:00 4a3bb116ee8ab2f912fdb6d2af40028b15825151 commit cb09cad44f07044d9810f18f6f9a6a6f3771f979 upstream. Probably a leftover from the early days of self-patching, p6nops are marked __initconst_or_module, which causes them to be discarded in a non-modular kernel. If something later triggers patching, it will overwrite kernel code with garbage. Reported-by: Tomas Racek <tracek@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Cc: Michael Tokarev <mjt@tls.msk.ru> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: qemu-devel@nongnu.org Cc: Anthony Liguori <anthony@codemonkey.ws> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/r/5034AE84.90708@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Ben Jencks <ben@bjencks.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit cb09cad44f07044d9810f18f6f9a6a6f3771f979 upstream.

Probably a leftover from the early days of self-patching, p6nops
are marked __initconst_or_module, which causes them to be
discarded in a non-modular kernel.  If something later triggers
patching, it will overwrite kernel code with garbage.

Reported-by: Tomas Racek <tracek@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Cc: Michael Tokarev <mjt@tls.msk.ru>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: qemu-devel@nongnu.org
Cc: Anthony Liguori <anthony@codemonkey.ws>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/r/5034AE84.90708@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Ben Jencks <ben@bjencks.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, nops: Missing break resulting in incorrect selection on Intel 2012-08-15T15:10:10+00:00 Alan Cox alan@linux.intel.com 2012-07-25T15:28:19+00:00 cabf5b0af54cec6a2f9ce674cbc96fc8aa2fc468 commit d6250a3f12edb3a86db9598ffeca3de8b4a219e9 upstream. The Intel case falls through into the generic case which then changes the values. For cases like the P6 it doesn't do the right thing so this seems to be a screwup. Signed-off-by: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/n/tip-lww2uirad4skzjlmrm0vru8o@git.kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit d6250a3f12edb3a86db9598ffeca3de8b4a219e9 upstream.

The Intel case falls through into the generic case which then changes
the values.  For cases like the P6 it doesn't do the right thing so
this seems to be a screwup.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-lww2uirad4skzjlmrm0vru8o@git.kernel.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86: Call stop_machine_text_poke() on all CPUs 2011-11-14T12:05:15+00:00 Rabin Vincent rabin@rab.in 2011-10-27T07:54:32+00:00 78345d2edc25e001558f3b7c85906f645d38d23c It appears that stop_machine_text_poke() wants to be called on all CPUs, like it's done from text_poke_smp(). Fix text_poke_smp_batch() to do this. Signed-off-by: Rabin Vincent <rabin@rab.in> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1319702072-32676-1-git-send-email-rabin@rab.in Signed-off-by: Ingo Molnar <mingo@elte.hu> 
It appears that stop_machine_text_poke() wants to be called on all CPUs,
like it's done from text_poke_smp().  Fix text_poke_smp_batch() to do
this.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Jason Baron <jbaron@redhat.com>
Link: http://lkml.kernel.org/r/1319702072-32676-1-git-send-email-rabin@rab.in
Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86-64: Move vread_tsc and vread_hpet into the vDSO 2011-07-15T00:57:05+00:00 Andy Lutomirski luto@mit.edu 2011-07-14T10:47:22+00:00 98d0ac38ca7b1b7a552c9a2359174ff84decb600 The vsyscall page now consists entirely of trap instructions. Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
The vsyscall page now consists entirely of trap instructions.

Cc: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86: Make alternative instruction pointers relative 2011-07-13T18:22:56+00:00 Andy Lutomirski luto@mit.edu 2011-07-13T13:24:10+00:00 59e97e4d6fbcd5b74a94cb48bcbfc6f8478a5e93 This save a few bytes on x86-64 and means that future patches can apply alternatives to unrelocated code. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
This save a few bytes on x86-64 and means that future patches can
apply alternatives to unrelocated code.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2011-05-20T00:55:12+00:00 Linus Torvalds torvalds@linux-foundation.org 2011-05-20T00:55:12+00:00 016281880439a8665ecf37514865742da58131d4 * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, cpu: Fix detection of Celeron Covington stepping A1 and B0 Documentation, ABI: Update L3 cache index disable text x86, AMD, cacheinfo: Fix L3 cache index disable checks x86, AMD, cacheinfo: Fix fallout caused by max3 conversion x86, cpu: Change NOP selection for certain Intel CPUs x86, cpu: Clean up and unify the NOP selection infrastructure x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4 x86, cpu: Move AMD Elan Kconfig under "Processor family" Fix up trivial conflicts in alternative handling (commit dc326fca2b64 "x86, cpu: Clean up and unify the NOP selection infrastructure" removed some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to CONFIG_JUMP_LABEL in the code that went away) 
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, cpu: Fix detection of Celeron Covington stepping A1 and B0
  Documentation, ABI: Update L3 cache index disable text
  x86, AMD, cacheinfo: Fix L3 cache index disable checks
  x86, AMD, cacheinfo: Fix fallout caused by max3 conversion
  x86, cpu: Change NOP selection for certain Intel CPUs
  x86, cpu: Clean up and unify the NOP selection infrastructure
  x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4
  x86, cpu: Move AMD Elan Kconfig under "Processor family"

Fix up trivial conflicts in alternative handling (commit dc326fca2b64
"x86, cpu: Clean up and unify the NOP selection infrastructure" removed
some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump
label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to
CONFIG_JUMP_LABEL in the code that went away)
Merge branch 'x86/mem' into perf/core 2011-05-18T18:59:30+00:00 Ingo Molnar mingo@elte.hu 2011-05-18T18:59:27+00:00 01ed58abec07633791f03684b937a7e22e00c9bb Merge reason: memcpy_64.S changes an assumption perf bench has, so merge this here so we can fix it. Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Merge reason: memcpy_64.S changes an assumption perf bench has, so merge this
              here so we can fix it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
x86, alternative, doc: Add comment for applying alternatives order 2011-05-17T22:40:25+00:00 Fenghua Yu fenghua.yu@intel.com 2011-05-17T22:29:12+00:00 509731336313b3799cf03071d72c64fa6383895e 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> 
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>
x86, cpu: Change NOP selection for certain Intel CPUs 2011-04-18T23:40:32+00:00 H. Peter Anvin hpa@linux.intel.com 2011-04-18T22:31:57+00:00 d8d9766c8c29f71c37bc4b74cc9fcf6a192c9bfd Due to a decoder implementation quirk, some specific Intel CPUs actually perform better with the "k8_nops" than with the SDM-recommended NOPs. For runtime-selected NOPs, if we detect those specific CPUs then use the k8_nops instead of the ones we would normally use. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1303166160-10315-4-git-send-email-hpa@linux.intel.com 
Due to a decoder implementation quirk, some specific Intel CPUs
actually perform better with the "k8_nops" than with the
SDM-recommended NOPs.  For runtime-selected NOPs, if we detect those
specific CPUs then use the k8_nops instead of the ones we would
normally use.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Link: http://lkml.kernel.org/r/1303166160-10315-4-git-send-email-hpa@linux.intel.com
x86, cpu: Clean up and unify the NOP selection infrastructure 2011-04-18T23:40:21+00:00 H. Peter Anvin hpa@linux.intel.com 2011-04-18T22:19:51+00:00 dc326fca2b640fc41aed7c015d0f456935a66255 Clean up and unify the NOP selection infrastructure: - Make the atomic 5-byte NOP a part of the selection system. - Pick NOPs once during early boot and then be done with it. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1303166160-10315-3-git-send-email-hpa@linux.intel.com 
Clean up and unify the NOP selection infrastructure:

- Make the atomic 5-byte NOP a part of the selection system.
- Pick NOPs once during early boot and then be done with it.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Link: http://lkml.kernel.org/r/1303166160-10315-3-git-send-email-hpa@linux.intel.com