<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/mips/kernel/asm-offsets.c, branch v4.1.17</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc</title>
<updated>2015-04-15T20:53:55+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-04-15T20:53:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=fa2e5c073a355465a2a8c9a2fbecf404f9857c3a'/>
<id>fa2e5c073a355465a2a8c9a2fbecf404f9857c3a</id>
<content type='text'>
Pull exec domain removal from Richard Weinberger:
 "This series removes execution domain support from Linux.

  The idea behind exec domains was to support different ABIs.  The
  feature was never complete nor stable.  Let's rip it out and make the
  kernel signal handling code less complicated"

* 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits)
  arm64: Removed unused variable
  sparc: Fix execution domain removal
  Remove rest of exec domains.
  arch: Remove exec_domain from remaining archs
  arc: Remove signal translation and exec_domain
  xtensa: Remove signal translation and exec_domain
  xtensa: Autogenerate offsets in struct thread_info
  x86: Remove signal translation and exec_domain
  unicore32: Remove signal translation and exec_domain
  um: Remove signal translation and exec_domain
  tile: Remove signal translation and exec_domain
  sparc: Remove signal translation and exec_domain
  sh: Remove signal translation and exec_domain
  s390: Remove signal translation and exec_domain
  mn10300: Remove signal translation and exec_domain
  microblaze: Remove signal translation and exec_domain
  m68k: Remove signal translation and exec_domain
  m32r: Remove signal translation and exec_domain
  m32r: Autogenerate offsets in struct thread_info
  frv: Remove signal translation and exec_domain
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull exec domain removal from Richard Weinberger:
 "This series removes execution domain support from Linux.

  The idea behind exec domains was to support different ABIs.  The
  feature was never complete nor stable.  Let's rip it out and make the
  kernel signal handling code less complicated"

* 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (27 commits)
  arm64: Removed unused variable
  sparc: Fix execution domain removal
  Remove rest of exec domains.
  arch: Remove exec_domain from remaining archs
  arc: Remove signal translation and exec_domain
  xtensa: Remove signal translation and exec_domain
  xtensa: Autogenerate offsets in struct thread_info
  x86: Remove signal translation and exec_domain
  unicore32: Remove signal translation and exec_domain
  um: Remove signal translation and exec_domain
  tile: Remove signal translation and exec_domain
  sparc: Remove signal translation and exec_domain
  sh: Remove signal translation and exec_domain
  s390: Remove signal translation and exec_domain
  mn10300: Remove signal translation and exec_domain
  microblaze: Remove signal translation and exec_domain
  m68k: Remove signal translation and exec_domain
  m32r: Remove signal translation and exec_domain
  m32r: Autogenerate offsets in struct thread_info
  frv: Remove signal translation and exec_domain
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>arch: Remove exec_domain from remaining archs</title>
<updated>2015-04-12T19:03:30+00:00</updated>
<author>
<name>Richard Weinberger</name>
<email>richard@nod.at</email>
</author>
<published>2015-03-30T05:30:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=fa41b1c7dfa0453931afb32c9988af67a2ee28ae'/>
<id>fa41b1c7dfa0453931afb32c9988af67a2ee28ae</id>
<content type='text'>
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: KVM: Add base guest MSA support</title>
<updated>2015-03-27T21:25:19+00:00</updated>
<author>
<name>James Hogan</name>
<email>james.hogan@imgtec.com</email>
</author>
<published>2015-03-05T11:43:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=539cb89fbdfe082d00be6f83d0f2140b7802151c'/>
<id>539cb89fbdfe082d00be6f83d0f2140b7802151c</id>
<content type='text'>
Add base code for supporting the MIPS SIMD Architecture (MSA) in MIPS
KVM guests. MSA cannot yet be enabled in the guest, we're just laying
the groundwork.

As with the FPU, whether the guest's MSA context is loaded is stored in
another bit in the fpu_inuse vcpu member. This allows MSA to be disabled
when the guest disables it, but keeping the MSA context loaded so it
doesn't have to be reloaded if the guest re-enables it.

New assembly code is added for saving and restoring the MSA context,
restoring only the upper half of the MSA context (for if the FPU context
is already loaded) and for saving/clearing and restoring MSACSR (which
can itself cause an MSA FP exception depending on the value). The MSACSR
is restored before returning to the guest if MSA is already enabled, and
the existing FP exception die notifier is extended to catch the possible
MSA FP exception and step over the ctcmsa instruction.

The helper function kvm_own_msa() is added to enable MSA and restore
the MSA context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use MSA for the first time and
triggers an MSA disabled exception.

The existing FPU helpers are extended to handle MSA. kvm_lose_fpu()
saves the full MSA context if it is loaded (which includes the FPU
context) and both kvm_lose_fpu() and kvm_drop_fpu() disable MSA.

kvm_own_fpu() also needs to lose any MSA context if FR=0, since there
would be a risk of getting reserved instruction exceptions if CU1 is
enabled and we later try and save the MSA context. We shouldn't usually
hit this case since it will be handled when emulating CU1 changes,
however there's nothing to stop the guest modifying the Status register
directly via the comm page, which will cause this case to get hit.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add base code for supporting the MIPS SIMD Architecture (MSA) in MIPS
KVM guests. MSA cannot yet be enabled in the guest, we're just laying
the groundwork.

As with the FPU, whether the guest's MSA context is loaded is stored in
another bit in the fpu_inuse vcpu member. This allows MSA to be disabled
when the guest disables it, but keeping the MSA context loaded so it
doesn't have to be reloaded if the guest re-enables it.

New assembly code is added for saving and restoring the MSA context,
restoring only the upper half of the MSA context (for if the FPU context
is already loaded) and for saving/clearing and restoring MSACSR (which
can itself cause an MSA FP exception depending on the value). The MSACSR
is restored before returning to the guest if MSA is already enabled, and
the existing FP exception die notifier is extended to catch the possible
MSA FP exception and step over the ctcmsa instruction.

The helper function kvm_own_msa() is added to enable MSA and restore
the MSA context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use MSA for the first time and
triggers an MSA disabled exception.

The existing FPU helpers are extended to handle MSA. kvm_lose_fpu()
saves the full MSA context if it is loaded (which includes the FPU
context) and both kvm_lose_fpu() and kvm_drop_fpu() disable MSA.

kvm_own_fpu() also needs to lose any MSA context if FR=0, since there
would be a risk of getting reserved instruction exceptions if CU1 is
enabled and we later try and save the MSA context. We shouldn't usually
hit this case since it will be handled when emulating CU1 changes,
however there's nothing to stop the guest modifying the Status register
directly via the comm page, which will cause this case to get hit.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: KVM: Add base guest FPU support</title>
<updated>2015-03-27T21:25:14+00:00</updated>
<author>
<name>James Hogan</name>
<email>james.hogan@imgtec.com</email>
</author>
<published>2014-11-18T14:09:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=98e91b8457d81f53fab990fac6c57e2a43c47627'/>
<id>98e91b8457d81f53fab990fac6c57e2a43c47627</id>
<content type='text'>
Add base code for supporting FPU in MIPS KVM guests. The FPU cannot yet
be enabled in the guest, we're just laying the groundwork.

Whether the guest's FPU context is loaded is stored in a bit in the
fpu_inuse vcpu member. This allows the FPU to be disabled when the guest
disables it, but keeping the FPU context loaded so it doesn't have to be
reloaded if the guest re-enables it.

An fpu_enabled vcpu member stores whether userland has enabled the FPU
capability (which will be wired up in a later patch).

New assembly code is added for saving and restoring the FPU context, and
for saving/clearing and restoring FCSR (which can itself cause an FP
exception depending on the value). The FCSR is restored before returning
to the guest if the FPU is already enabled, and a die notifier is
registered to catch the possible FP exception and step over the ctc1
instruction.

The helper function kvm_lose_fpu() is added to save FPU context and
disable the FPU, which is used when saving hardware state before a
context switch or KVM exit (the vcpu_get_regs() callback).

The helper function kvm_own_fpu() is added to enable the FPU and restore
the FPU context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use the FPU for the first time
and triggers a co-processor unusable exception.

The helper function kvm_drop_fpu() is added to discard the FPU context
and disable the FPU, which will be used in a later patch when the FPU
state will become architecturally UNPREDICTABLE (change of FR mode) to
force a reload of [stale] context in the new FR mode.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add base code for supporting FPU in MIPS KVM guests. The FPU cannot yet
be enabled in the guest, we're just laying the groundwork.

Whether the guest's FPU context is loaded is stored in a bit in the
fpu_inuse vcpu member. This allows the FPU to be disabled when the guest
disables it, but keeping the FPU context loaded so it doesn't have to be
reloaded if the guest re-enables it.

An fpu_enabled vcpu member stores whether userland has enabled the FPU
capability (which will be wired up in a later patch).

New assembly code is added for saving and restoring the FPU context, and
for saving/clearing and restoring FCSR (which can itself cause an FP
exception depending on the value). The FCSR is restored before returning
to the guest if the FPU is already enabled, and a die notifier is
registered to catch the possible FP exception and step over the ctc1
instruction.

The helper function kvm_lose_fpu() is added to save FPU context and
disable the FPU, which is used when saving hardware state before a
context switch or KVM exit (the vcpu_get_regs() callback).

The helper function kvm_own_fpu() is added to enable the FPU and restore
the FPU context if it isn't already loaded, which will be used in a
later patch when the guest attempts to use the FPU for the first time
and triggers a co-processor unusable exception.

The helper function kvm_drop_fpu() is added to discard the FPU context
and disable the FPU, which will be used in a later patch when the FPU
state will become architecturally UNPREDICTABLE (change of FR mode) to
force a reload of [stale] context in the new FR mode.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "MIPS: Don't assume 64-bit FP registers for context switch"</title>
<updated>2015-03-27T18:42:48+00:00</updated>
<author>
<name>James Hogan</name>
<email>james.hogan@imgtec.com</email>
</author>
<published>2015-01-30T12:09:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=466aec5f292be469e15b3dc3d17b731dab93727c'/>
<id>466aec5f292be469e15b3dc3d17b731dab93727c</id>
<content type='text'>
This reverts commit 02987633df7ba2f62967791dda816eb191d1add3.

The basic premise of the patch was incorrect since MSA context
(including FP state) is saved using st.d which stores two consecutive
64-bit words in memory rather than a single 128-bit word. This means
that even with big endian MSA, the FP state is still in the first 64-bit
word.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9168/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit 02987633df7ba2f62967791dda816eb191d1add3.

The basic premise of the patch was incorrect since MSA context
(including FP state) is saved using st.d which stores two consecutive
64-bit words in memory rather than a single 128-bit word. This means
that even with big endian MSA, the FP state is still in the first 64-bit
word.

Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9168/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus</title>
<updated>2015-02-22T03:41:38+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-02-22T03:41:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=a135c717d5cdb311cff7661af4c17fef0562e590'/>
<id>a135c717d5cdb311cff7661af4c17fef0562e590</id>
<content type='text'>
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS:

   - a number of fixes that didn't make the 3.19 release.

   - a number of cleanups.

   - preliminary support for Cavium's Octeon 3 SOCs which feature up to
     48 MIPS64 R3 cores with FPU and hardware virtualization.

   - support for MIPS R6 processors.

     Revision 6 of the MIPS architecture is a major revision of the MIPS
     architecture which does away with many of original sins of the
     architecture such as branch delay slots.  This and other changes in
     R6 require major changes throughout the entire MIPS core
     architecture code and make up for the lion share of this pull
     request.

   - finally some preparatory work for eXtendend Physical Address
     support, which allows support of up to 40 bit of physical address
     space on 32 bit processors"

     [ Ahh, MIPS can't leave the PAE brain damage alone.  It's like
       every CPU architect has to make that mistake, but pee in the snow
       by changing the TLA.  But whether it's called PAE, LPAE or XPA,
       it's horrid crud   - Linus ]

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
  MIPS: sead3: Corrected get_c0_perfcount_int
  MIPS: mm: Remove dead macro definitions
  MIPS: OCTEON: irq: add CIB and other fixes
  MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
  MIPS: OCTEON: More OCTEONIII support
  MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
  MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
  MIPS: OCTEON: Update octeon-model.h code for new SoCs.
  MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
  MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
  MIPS: OCTEON: Implement the core-16057 workaround
  MIPS: OCTEON: Delete unused COP2 saving code
  MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
  MIPS: OCTEON: Save and restore CP2 SHA3 state
  MIPS: OCTEON: Fix FP context save.
  MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
  MIPS: boot: Provide more uImage options
  MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
  MIPS: ip22-gio: Remove legacy suspend/resume support
  mips: pci: Add ifdef around pci_proc_domain
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS:

   - a number of fixes that didn't make the 3.19 release.

   - a number of cleanups.

   - preliminary support for Cavium's Octeon 3 SOCs which feature up to
     48 MIPS64 R3 cores with FPU and hardware virtualization.

   - support for MIPS R6 processors.

     Revision 6 of the MIPS architecture is a major revision of the MIPS
     architecture which does away with many of original sins of the
     architecture such as branch delay slots.  This and other changes in
     R6 require major changes throughout the entire MIPS core
     architecture code and make up for the lion share of this pull
     request.

   - finally some preparatory work for eXtendend Physical Address
     support, which allows support of up to 40 bit of physical address
     space on 32 bit processors"

     [ Ahh, MIPS can't leave the PAE brain damage alone.  It's like
       every CPU architect has to make that mistake, but pee in the snow
       by changing the TLA.  But whether it's called PAE, LPAE or XPA,
       it's horrid crud   - Linus ]

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
  MIPS: sead3: Corrected get_c0_perfcount_int
  MIPS: mm: Remove dead macro definitions
  MIPS: OCTEON: irq: add CIB and other fixes
  MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
  MIPS: OCTEON: More OCTEONIII support
  MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
  MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
  MIPS: OCTEON: Update octeon-model.h code for new SoCs.
  MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
  MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
  MIPS: OCTEON: Implement the core-16057 workaround
  MIPS: OCTEON: Delete unused COP2 saving code
  MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
  MIPS: OCTEON: Save and restore CP2 SHA3 state
  MIPS: OCTEON: Fix FP context save.
  MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
  MIPS: boot: Provide more uImage options
  MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
  MIPS: ip22-gio: Remove legacy suspend/resume support
  mips: pci: Add ifdef around pci_proc_domain
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: OCTEON: Save and restore CP2 SHA3 state</title>
<updated>2015-02-20T14:29:08+00:00</updated>
<author>
<name>David Daney</name>
<email>david.daney@cavium.com</email>
</author>
<published>2015-01-15T13:11:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6b3a287e6351b00df6624b41c160e1c0817f40e2'/>
<id>6b3a287e6351b00df6624b41c160e1c0817f40e2</id>
<content type='text'>
Allocate new save space, and then save/restore the registers if
OCTEON III.

Signed-off-by: David Daney &lt;david.daney@cavium.com&gt;
Signed-off-by: Aleksey Makarov &lt;aleksey.makarov@auriga.com&gt;
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8935/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Allocate new save space, and then save/restore the registers if
OCTEON III.

Signed-off-by: David Daney &lt;david.daney@cavium.com&gt;
Signed-off-by: Aleksey Makarov &lt;aleksey.makarov@auriga.com&gt;
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8935/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: Make use of the ERETNC instruction on MIPS R6</title>
<updated>2015-02-17T15:37:37+00:00</updated>
<author>
<name>Markos Chandras</name>
<email>markos.chandras@imgtec.com</email>
</author>
<published>2014-12-03T12:37:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=7c151d3d5d7a032e08dbe86ad6088622391bf13e'/>
<id>7c151d3d5d7a032e08dbe86ad6088622391bf13e</id>
<content type='text'>
The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.

Signed-off-by: Markos Chandras &lt;markos.chandras@imgtec.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.

Signed-off-by: Markos Chandras &lt;markos.chandras@imgtec.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>all arches, signal: move restart_block to struct task_struct</title>
<updated>2015-02-13T02:54:12+00:00</updated>
<author>
<name>Andy Lutomirski</name>
<email>luto@amacapital.net</email>
</author>
<published>2015-02-12T23:01:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f56141e3e2d9aabf7e6b89680ab572c2cdbb2a24'/>
<id>f56141e3e2d9aabf7e6b89680ab572c2cdbb2a24</id>
<content type='text'>
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: David Miller &lt;davem@davemloft.net&gt;
Acked-by: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Russell King &lt;rmk@arm.linux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Steven Miao &lt;realmz6@gmail.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Aurelien Jacquiot &lt;a-jacquiot@ti.com&gt;
Cc: Mikael Starvik &lt;starvik@axis.com&gt;
Cc: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Richard Kuo &lt;rkuo@codeaurora.org&gt;
Cc: "Luck, Tony" &lt;tony.luck@intel.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Jonas Bonn &lt;jonas@southpole.se&gt;
Cc: "James E.J. Bottomley" &lt;jejb@parisc-linux.org&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Tested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Chen Liqin &lt;liqin.linux@gmail.com&gt;
Cc: Lennox Wu &lt;lennox.wu@gmail.com&gt;
Cc: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
Cc: Guan Xuetao &lt;gxt@mprc.pku.edu.cn&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: David Miller &lt;davem@davemloft.net&gt;
Acked-by: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Richard Henderson &lt;rth@twiddle.net&gt;
Cc: Ivan Kokshaysky &lt;ink@jurassic.park.msu.ru&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Russell King &lt;rmk@arm.linux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Haavard Skinnemoen &lt;hskinnemoen@gmail.com&gt;
Cc: Hans-Christian Egtvedt &lt;egtvedt@samfundet.no&gt;
Cc: Steven Miao &lt;realmz6@gmail.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Aurelien Jacquiot &lt;a-jacquiot@ti.com&gt;
Cc: Mikael Starvik &lt;starvik@axis.com&gt;
Cc: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Richard Kuo &lt;rkuo@codeaurora.org&gt;
Cc: "Luck, Tony" &lt;tony.luck@intel.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Jonas Bonn &lt;jonas@southpole.se&gt;
Cc: "James E.J. Bottomley" &lt;jejb@parisc-linux.org&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Tested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Chen Liqin &lt;liqin.linux@gmail.com&gt;
Cc: Lennox Wu &lt;lennox.wu@gmail.com&gt;
Cc: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
Cc: Guan Xuetao &lt;gxt@mprc.pku.edu.cn&gt;
Cc: Chris Zankel &lt;chris@zankel.net&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: save/restore MSACSR register on context switch</title>
<updated>2014-08-01T22:06:43+00:00</updated>
<author>
<name>Paul Burton</name>
<email>paul.burton@imgtec.com</email>
</author>
<published>2014-07-11T15:44:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f7a46fa7bb0047d3e226702a0c4b786862fe6843'/>
<id>f7a46fa7bb0047d3e226702a0c4b786862fe6843</id>
<content type='text'>
I added a field for the MSACSR register in struct mips_fpu_struct, but
never actually made use of it... This is a clear bug. Save and restore
the MSACSR register along with the vector registers.

Signed-off-by: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7300/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
I added a field for the MSACSR register in struct mips_fpu_struct, but
never actually made use of it... This is a clear bug. Save and restore
the MSACSR register along with the vector registers.

Signed-off-by: Paul Burton &lt;paul.burton@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7300/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
