linux-stable.git/arch/x86, branch linux-3.3.y Linux kernel stable tree MCE: Fix vm86 handling for 32bit mce handler 2012-06-01T07:15:55+00:00 Andi Kleen andi@firstfloor.org 2010-11-19T12:16:22+00:00 8fa23b6a048234f83c790a82bbcc6e23a6826b5d commit a129a7c84582629741e5fa6f40026efcd7a65bd4 upstream. When running on 32bit the mce handler could misinterpret vm86 mode as ring 0. This can affect whether it does recovery or not; it was possible to panic when recovery was actually possible. Fix this by always forcing vm86 to look like ring 3. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a129a7c84582629741e5fa6f40026efcd7a65bd4 upstream.

When running on 32bit the mce handler could misinterpret
vm86 mode as ring 0. This can affect whether it does recovery
or not; it was possible to panic when recovery was actually
possible.

Fix this by always forcing vm86 to look like ring 3.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/mce: Fix check for processor context when machine check was taken. 2012-06-01T07:15:53+00:00 Tony Luck tony.luck@intel.com 2012-05-23T21:14:22+00:00 fd1a48fe1d6813c141c890541951fcb54b0f20d7 commit 875e26648cf9b6db9d8dc07b7959d7c61fb3f49c upstream. Linus pointed out that there was no value is checking whether m->ip was zero - because zero is a legimate value. If we have a reliable (or faked in the VM86 case) "m->cs" we can use it to tell whether we were in user mode or kernelwhen the machine check hit. Reported-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 875e26648cf9b6db9d8dc07b7959d7c61fb3f49c upstream.

Linus pointed out that there was no value is checking whether m->ip
was zero - because zero is a legimate value.  If we have a reliable
(or faked in the VM86 case) "m->cs" we can use it to tell whether we
were in user mode or kernelwhen the machine check hit.

Reported-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, relocs: Add jiffies and jiffies_64 to the relative whitelist 2012-06-01T07:15:53+00:00 H. Peter Anvin hpa@zytor.com 2012-05-24T14:01:38+00:00 43504f70a86b70d4e6eab50b0d46fefe685876be commit ea17e7414bc62e8d3bde8d08e3df1d921c518c17 upstream. The symbol jiffies is created in the linker script as an alias to jiffies_64. Unfortunately this is done outside any section, and apparently GNU ld 2.21 doesn't carry the section with it, so we end up with an absolute symbol and therefore a broken kernel. Add jiffies and jiffies_64 to the whitelist. The most disturbing bit with this discovery is that it shows that we have had multiple linker bugs in this area crossing multiple generations, and have been silently building bad kernels for some time. Link: http://lkml.kernel.org/r/20120524171604.0d98284f3affc643e9714470@canb.auug.org.au Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ea17e7414bc62e8d3bde8d08e3df1d921c518c17 upstream.

The symbol jiffies is created in the linker script as an alias to
jiffies_64.  Unfortunately this is done outside any section, and
apparently GNU ld 2.21 doesn't carry the section with it, so we end up
with an absolute symbol and therefore a broken kernel.

Add jiffies and jiffies_64 to the whitelist.

The most disturbing bit with this discovery is that it shows that we
have had multiple linker bugs in this area crossing multiple
generations, and have been silently building bad kernels for some time.

Link: http://lkml.kernel.org/r/20120524171604.0d98284f3affc643e9714470@canb.auug.org.au
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86-32, relocs: Whitelist more symbols for ld bug workaround 2012-06-01T07:15:52+00:00 H. Peter Anvin hpa@zytor.com 2012-05-23T21:02:34+00:00 3a9a33e0157ecf06f70ef6791ce1dd30dac21b75 commit fd952815307f0f272bf49fd364a7fd2f9992bc42 upstream. As noted in checkin: a3e854d95 x86, relocs: Workaround for binutils 2.22.52.0.1 section bug ld version 2.22.52.0.[12] can incorrectly promote relative symbols to absolute, if the output section they appear in is otherwise empty. Since checkin: 6520fe55 x86, realmode: 16-bit real-mode code support for relocs tool we actually check for this and error out rather than silently creating a kernel which will malfunction if relocated. Ingo found a configuration in which __start_builtin_fw triggered the warning. Go through the linker script sources and look for more symbols that could plausibly get bogusly promoted to absolute, and add them to the whitelist. In general, if the following error triggers: Invalid absolute R_386_32 relocation: <symbol> ... then we should verify that <symbol> is really meant to be relocated, and add it and any related symbols manually to the S_REL regexp. Please note that 6520fe55 does not introduce the error, only the check for the error -- without 6520fe55 this version of ld will simply produce a corrupt kernel if CONFIG_RELOCATABLE is set on x86-32. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fd952815307f0f272bf49fd364a7fd2f9992bc42 upstream.

As noted in checkin:

a3e854d95 x86, relocs: Workaround for binutils 2.22.52.0.1 section bug

ld version 2.22.52.0.[12] can incorrectly promote relative symbols to
absolute, if the output section they appear in is otherwise empty.

Since checkin:

6520fe55 x86, realmode: 16-bit real-mode code support for relocs tool

we actually check for this and error out rather than silently creating
a kernel which will malfunction if relocated.

Ingo found a configuration in which __start_builtin_fw triggered the
warning.

Go through the linker script sources and look for more symbols that
could plausibly get bogusly promoted to absolute, and add them to the
whitelist.

In general, if the following error triggers:

	Invalid absolute R_386_32 relocation: <symbol>

... then we should verify that <symbol> is really meant to be
relocated, and add it and any related symbols manually to the S_REL
regexp.

Please note that 6520fe55 does not introduce the error, only the check
for the error -- without 6520fe55 this version of ld will simply
produce a corrupt kernel if CONFIG_RELOCATABLE is set on x86-32.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, relocs: Build clean fix 2012-06-01T07:15:52+00:00 Jarkko Sakkinen jarkko.sakkinen@intel.com 2012-05-21T17:51:24+00:00 50a08146f2d2447d3e5e12b8458f096394891d70 commit b2d668da9307c4c163dd603d2bb3cadb10f9fd37 upstream. relocs was not cleaned up when "make clean" is issued. This patch fixes the issue. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Link: http://lkml.kernel.org/r/1337622684-6834-1-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b2d668da9307c4c163dd603d2bb3cadb10f9fd37 upstream.

relocs was not cleaned up when "make clean" is issued. This
patch fixes the issue.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1337622684-6834-1-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, relocs: When printing an error, say relative or absolute 2012-06-01T07:15:52+00:00 H. Peter Anvin hpa@linux.intel.com 2012-05-18T16:52:01+00:00 e27a45a6869d586cc2558373f9cd2ffdc005497c commit 24ab82bd9bf18f3efc69a131d73577940941e1b7 upstream. When the relocs tool throws an error, let the error message say if it is an absolute or relative symbol. This should make it a lot more clear what action the programmer needs to take and should help us find the reason if additional symbol bugs show up. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 24ab82bd9bf18f3efc69a131d73577940941e1b7 upstream.

When the relocs tool throws an error, let the error message say if it
is an absolute or relative symbol.  This should make it a lot more
clear what action the programmer needs to take and should help us find
the reason if additional symbol bugs show up.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, relocs: Workaround for binutils 2.22.52.0.1 section bug 2012-06-01T07:15:52+00:00 H. Peter Anvin hpa@linux.intel.com 2012-05-18T07:24:09+00:00 b3329716c886dca2b7cc105b7dc833c1525ba24c commit a3e854d95a76862cd37937e0b0438f540536771a upstream. GNU ld 2.22.52.0.1 has a bug that it blindly changes symbols from section-relative to absolute if they are in a section of zero length. This turns the symbols __init_begin and __init_end into absolute symbols. Let the relocs program know that those should be treated as relative symbols. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a3e854d95a76862cd37937e0b0438f540536771a upstream.

GNU ld 2.22.52.0.1 has a bug that it blindly changes symbols from
section-relative to absolute if they are in a section of zero length.
This turns the symbols __init_begin and __init_end into absolute
symbols.  Let the relocs program know that those should be treated as
relative symbols.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86, realmode: 16-bit real-mode code support for relocs tool 2012-06-01T07:15:52+00:00 H. Peter Anvin hpa@linux.intel.com 2012-05-08T18:22:24+00:00 fb24d9d9c13c7c6d0e1f4ae5301288be0e38fb8e commit 6520fe5564acf07ade7b18a1272db1184835c487 upstream. A new option is added to the relocs tool called '--realmode'. This option causes the generation of 16-bit segment relocations and 32-bit linear relocations for the real-mode code. When the real-mode code is moved to the low-memory during kernel initialization, these relocation entries can be used to relocate the code properly. In the assembly code 16-bit segment relocations must be relative to the 'real_mode_seg' absolute symbol. Linear relocations must be relative to a symbol prefixed with 'pa_'. 16-bit segment relocation is used to load cs:ip in 16-bit code. Linear relocations are used in the 32-bit code for relocatable data references. They are declared in the linker script of the real-mode code. The relocs tool is moved to arch/x86/tools/relocs.c, and added new target archscripts that can be used to build scripts needed building an architecture. be compiled before building the arch/x86 tree. [ hpa: accelerating this because it detects invalid absolute relocations, a serious bug in binutils 2.22.52.0.x which currently produces bad kernels. ] [ jsakkine: applied against 3.3.7 ] Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@iki.fi> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6520fe5564acf07ade7b18a1272db1184835c487 upstream.

A new option is added to the relocs tool called '--realmode'.
This option causes the generation of 16-bit segment relocations
and 32-bit linear relocations for the real-mode code. When
the real-mode code is moved to the low-memory during kernel
initialization, these relocation entries can be used to
relocate the code properly.

In the assembly code 16-bit segment relocations must be relative
to the 'real_mode_seg' absolute symbol. Linear relocations must be
relative to a symbol prefixed with 'pa_'.

16-bit segment relocation is used to load cs:ip in 16-bit code.
Linear relocations are used in the 32-bit code for relocatable
data references. They are declared in the linker script of the
real-mode code.

The relocs tool is moved to arch/x86/tools/relocs.c, and added new
target archscripts that can be used to build scripts needed building
an architecture.  be compiled before building the arch/x86 tree.

[ hpa: accelerating this because it detects invalid absolute
  relocations, a serious bug in binutils 2.22.52.0.x which currently
  produces bad kernels. ]

[ jsakkine: applied against 3.3.7 ]

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xen: do not map the same GSI twice in PVHVM guests. 2012-06-01T07:15:51+00:00 Stefano Stabellini stefano.stabellini@eu.citrix.com 2012-05-21T15:54:10+00:00 16f6501e8bd7d8f07cf76ef2bf0a188a97892c09 commit 68c2c39a76b094e9b2773e5846424ea674bf2c46 upstream. PV on HVM guests map GSIs into event channels. At restore time the event channels are resumed by restore_pirqs. Device drivers might try to register the same GSI again through ACPI at restore time, but the GSI has already been mapped and bound by restore_pirqs. This patch detects these situations and avoids mapping the same GSI multiple times. Without this patch we get: (XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped and waste a pirq. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 68c2c39a76b094e9b2773e5846424ea674bf2c46 upstream.

PV on HVM guests map GSIs into event channels. At restore time the
event channels are resumed by restore_pirqs.

Device drivers might try to register the same GSI again through ACPI at
restore time, but the GSI has already been mapped and bound by
restore_pirqs. This patch detects these situations and avoids
 mapping the same GSI multiple times.

Without this patch we get:
(XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped
and waste a pirq.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
perf/x86: Update event scheduling constraints for AMD family 15h models 2012-06-01T07:15:43+00:00 Robert Richter robert.richter@amd.com 2012-05-18T10:40:42+00:00 c110a3c6ef497b687b2e9777fe0e4cff7c587957 commit 5bcdf5e4fee3c45e1281c25e4941f2163cb28c65 upstream. This update is for newer family 15h cpu models from 0x02 to 0x1f. Signed-off-by: Robert Richter <robert.richter@amd.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1337337642-1621-1-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5bcdf5e4fee3c45e1281c25e4941f2163cb28c65 upstream.

This update is for newer family 15h cpu models from 0x02 to 0x1f.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1337337642-1621-1-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>