<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch, branch v4.1.41</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ARM: tegra: paz00: Mark panel regulator as enabled on boot</title>
<updated>2017-06-13T13:29:21+00:00</updated>
<author>
<name>Marc Dietrich</name>
<email>marvin24@gmx.de</email>
</author>
<published>2016-12-09T09:20:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=df8198865a0fad311689086b2d25e524bb178788'/>
<id>df8198865a0fad311689086b2d25e524bb178788</id>
<content type='text'>
[ Upstream commit 0c18927f51f4d390abdcf385bff5f995407ee732 ]

Current U-Boot enables the display already. Marking the regulator as
enabled on boot fixes sporadic panel initialization failures.

Signed-off-by: Marc Dietrich &lt;marvin24@gmx.de&gt;
Tested-by: Misha Komarovskiy &lt;zombah@gmail.com&gt;
Signed-off-by: Thierry Reding &lt;treding@nvidia.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0c18927f51f4d390abdcf385bff5f995407ee732 ]

Current U-Boot enables the display already. Marking the regulator as
enabled on boot fixes sporadic panel initialization failures.

Signed-off-by: Marc Dietrich &lt;marvin24@gmx.de&gt;
Tested-by: Misha Komarovskiy &lt;zombah@gmail.com&gt;
Signed-off-by: Thierry Reding &lt;treding@nvidia.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: R2-on-R6 MULTU/MADDU/MSUBU emulation bugfix</title>
<updated>2017-06-13T13:29:20+00:00</updated>
<author>
<name>Leonid Yegoshin</name>
<email>Leonid.Yegoshin@imgtec.com</email>
</author>
<published>2016-08-25T17:37:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=62494116045eac405cb83ab8a7c24c1c8b088892'/>
<id>62494116045eac405cb83ab8a7c24c1c8b088892</id>
<content type='text'>
[ Upstream commit d65e5677ad5b3a49c43f60ec07644dc1f87bbd2e ]

MIPS instructions MULTU, MADDU and MSUBU emulation requires registers HI/LO
to be converted to signed 32bits before 64bit sign extension on MIPS64.

Bug was found on running MIPS32 R2 test application on MIPS64 R6 kernel.

Fixes: b0a668fb2038 ("MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6")
Signed-off-by: Leonid Yegoshin &lt;Leonid.Yegoshin@imgtec.com&gt;
Reported-by: Nikola.Veljkovic@imgtec.com
Cc: paul.burton@imgtec.com
Cc: yamada.masahiro@socionext.com
Cc: akpm@linux-foundation.org
Cc: andrea.gelmini@gelma.net
Cc: macro@imgtec.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14043/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d65e5677ad5b3a49c43f60ec07644dc1f87bbd2e ]

MIPS instructions MULTU, MADDU and MSUBU emulation requires registers HI/LO
to be converted to signed 32bits before 64bit sign extension on MIPS64.

Bug was found on running MIPS32 R2 test application on MIPS64 R6 kernel.

Fixes: b0a668fb2038 ("MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6")
Signed-off-by: Leonid Yegoshin &lt;Leonid.Yegoshin@imgtec.com&gt;
Reported-by: Nikola.Veljkovic@imgtec.com
Cc: paul.burton@imgtec.com
Cc: yamada.masahiro@socionext.com
Cc: akpm@linux-foundation.org
Cc: andrea.gelmini@gelma.net
Cc: macro@imgtec.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14043/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: nVMX: initialize PML fields in vmcs02</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Ladi Prosek</name>
<email>lprosek@redhat.com</email>
</author>
<published>2017-04-04T12:18:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0a9f0af48e3fdc0b2213dd7b39b36658ace02c4d'/>
<id>0a9f0af48e3fdc0b2213dd7b39b36658ace02c4d</id>
<content type='text'>
[ Upstream commit 1fb883bb827ee8efc1cc9ea0154f953f8a219d38 ]

L2 was running with uninitialized PML fields which led to incomplete
dirty bitmap logging. This manifested as all kinds of subtle erratic
behavior of the nested guest.

Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX")
Signed-off-by: Ladi Prosek &lt;lprosek@redhat.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1fb883bb827ee8efc1cc9ea0154f953f8a219d38 ]

L2 was running with uninitialized PML fields which led to incomplete
dirty bitmap logging. This manifested as all kinds of subtle erratic
behavior of the nested guest.

Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX")
Signed-off-by: Ladi Prosek &lt;lprosek@redhat.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "KVM: nested VMX: disable perf cpuid reporting"</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Jim Mattson</name>
<email>jmattson@google.com</email>
</author>
<published>2016-12-21T00:34:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4736ccc83dfca59e589eae8c183ecd0d579e75a2'/>
<id>4736ccc83dfca59e589eae8c183ecd0d579e75a2</id>
<content type='text'>
[ Upstream commit 0b4c208d443ba2af82b4c70f99ca8df31e9a0020 ]

This reverts commit bc6134942dbbf31c25e9bd7c876be5da81c9e1ce.

A CPUID instruction executed in VMX non-root mode always causes a
VM-exit, regardless of the leaf being queried.

Fixes: bc6134942dbb ("KVM: nested VMX: disable perf cpuid reporting")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
[The issue solved by bc6134942dbb has been resolved with ff651cb613b4
 ("KVM: nVMX: Add nested msr load/restore algorithm").]
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;

Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0b4c208d443ba2af82b4c70f99ca8df31e9a0020 ]

This reverts commit bc6134942dbbf31c25e9bd7c876be5da81c9e1ce.

A CPUID instruction executed in VMX non-root mode always causes a
VM-exit, regardless of the leaf being queried.

Fixes: bc6134942dbb ("KVM: nested VMX: disable perf cpuid reporting")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
[The issue solved by bc6134942dbb has been resolved with ff651cb613b4
 ("KVM: nVMX: Add nested msr load/restore algorithm").]
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;

Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/platform/intel-mid: Correct MSI IRQ line for watchdog device</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Andy Shevchenko</name>
<email>andriy.shevchenko@linux.intel.com</email>
</author>
<published>2017-03-12T15:07:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7a07dbb8c25c3a9c2d9461d22faf38436c160239'/>
<id>7a07dbb8c25c3a9c2d9461d22faf38436c160239</id>
<content type='text'>
[ Upstream commit 80354c29025833acd72ddac1ffa21c6cb50128cd ]

The interrupt line used for the watchdog is 12, according to the official
Intel Edison BSP code.

And indeed after fixing it we start getting an interrupt and thus the
watchdog starts working again:

  [  191.699951] Kernel panic - not syncing: Kernel Watchdog

Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: David Cohen &lt;david.a.cohen@linux.intel.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 78a3bb9e408b ("x86: intel-mid: add watchdog platform code for Merrifield")
Link: http://lkml.kernel.org/r/20170312150744.45493-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 80354c29025833acd72ddac1ffa21c6cb50128cd ]

The interrupt line used for the watchdog is 12, according to the official
Intel Edison BSP code.

And indeed after fixing it we start getting an interrupt and thus the
watchdog starts working again:

  [  191.699951] Kernel panic - not syncing: Kernel Watchdog

Signed-off-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: David Cohen &lt;david.a.cohen@linux.intel.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 78a3bb9e408b ("x86: intel-mid: add watchdog platform code for Merrifield")
Link: http://lkml.kernel.org/r/20170312150744.45493-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kprobes/x86: Fix kernel panic when certain exception-handling addresses are probed</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2017-02-28T16:23:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=92e01bd47512f985548f930ce771b124068e3af2'/>
<id>92e01bd47512f985548f930ce771b124068e3af2</id>
<content type='text'>
[ Upstream commit 75013fb16f8484898eaa8d0b08fed942d790f029 ]

Fix to the exception table entry check by using probed address
instead of the address of copied instruction.

This bug may cause unexpected kernel panic if user probe an address
where an exception can happen which should be fixup by __ex_table
(e.g. copy_from_user.)

Unless user puts a kprobe on such address, this doesn't
cause any problem.

This bug has been introduced years ago, by commit:

  464846888d9a ("x86/kprobes: Fix a bug which can modify kernel code permanently").

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 464846888d9a ("x86/kprobes: Fix a bug which can modify kernel code permanently")
Link: http://lkml.kernel.org/r/148829899399.28855.12581062400757221722.stgit@devbox
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 75013fb16f8484898eaa8d0b08fed942d790f029 ]

Fix to the exception table entry check by using probed address
instead of the address of copied instruction.

This bug may cause unexpected kernel panic if user probe an address
where an exception can happen which should be fixup by __ex_table
(e.g. copy_from_user.)

Unless user puts a kprobe on such address, this doesn't
cause any problem.

This bug has been introduced years ago, by commit:

  464846888d9a ("x86/kprobes: Fix a bug which can modify kernel code permanently").

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 464846888d9a ("x86/kprobes: Fix a bug which can modify kernel code permanently")
Link: http://lkml.kernel.org/r/148829899399.28855.12581062400757221722.stgit@devbox
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/pci-calgary: Fix iommu_free() comparison of unsigned expression &gt;= 0</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Nikola Pajkovsky</name>
<email>npajkovsky@suse.cz</email>
</author>
<published>2016-11-15T08:47:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=19d416eaccbbac6f410d3d4a3fa4b51b2e22fbb0'/>
<id>19d416eaccbbac6f410d3d4a3fa4b51b2e22fbb0</id>
<content type='text'>
[ Upstream commit 68dee8e2f2cacc54d038394e70d22411dee89da2 ]

commit 8fd524b355da ("x86: Kill bad_dma_address variable") has killed
bad_dma_address variable and used instead of macro DMA_ERROR_CODE
which is always zero. Since dma_addr is unsigned, the statement

   dma_addr &gt;= DMA_ERROR_CODE

is always true, and not needed.

arch/x86/kernel/pci-calgary_64.c: In function ‘iommu_free’:
arch/x86/kernel/pci-calgary_64.c:299:2: warning: comparison of unsigned expression &gt;= 0 is always true [-Wtype-limits]
  if (unlikely((dma_addr &gt;= DMA_ERROR_CODE) &amp;&amp; (dma_addr &lt; badend))) {

Fixes: 8fd524b355da ("x86: Kill bad_dma_address variable")
Signed-off-by: Nikola Pajkovsky &lt;npajkovsky@suse.cz&gt;
Cc: iommu@lists.linux-foundation.org
Cc: Jon Mason &lt;jdmason@kudzu.us&gt;
Cc: Muli Ben-Yehuda &lt;mulix@mulix.org&gt;
Link: http://lkml.kernel.org/r/7612c0f9dd7c1290407dbf8e809def922006920b.1479161177.git.npajkovsky@suse.cz
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 68dee8e2f2cacc54d038394e70d22411dee89da2 ]

commit 8fd524b355da ("x86: Kill bad_dma_address variable") has killed
bad_dma_address variable and used instead of macro DMA_ERROR_CODE
which is always zero. Since dma_addr is unsigned, the statement

   dma_addr &gt;= DMA_ERROR_CODE

is always true, and not needed.

arch/x86/kernel/pci-calgary_64.c: In function ‘iommu_free’:
arch/x86/kernel/pci-calgary_64.c:299:2: warning: comparison of unsigned expression &gt;= 0 is always true [-Wtype-limits]
  if (unlikely((dma_addr &gt;= DMA_ERROR_CODE) &amp;&amp; (dma_addr &lt; badend))) {

Fixes: 8fd524b355da ("x86: Kill bad_dma_address variable")
Signed-off-by: Nikola Pajkovsky &lt;npajkovsky@suse.cz&gt;
Cc: iommu@lists.linux-foundation.org
Cc: Jon Mason &lt;jdmason@kudzu.us&gt;
Cc: Muli Ben-Yehuda &lt;mulix@mulix.org&gt;
Link: http://lkml.kernel.org/r/7612c0f9dd7c1290407dbf8e809def922006920b.1479161177.git.npajkovsky@suse.cz
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/powernv: Fix opal_exit tracepoint opcode</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Michael Ellerman</name>
<email>mpe@ellerman.id.au</email>
</author>
<published>2017-02-07T10:01:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ab1b642339b38c8ddaceb65b03ec6bb589c82b7e'/>
<id>ab1b642339b38c8ddaceb65b03ec6bb589c82b7e</id>
<content type='text'>
[ Upstream commit a7e0fb6c2029a780444d09560f739e020d54fe4d ]

Currently the opal_exit tracepoint usually shows the opcode as 0:

  &lt;idle&gt;-0     [047] d.h.   635.654292: opal_entry: opcode=63
  &lt;idle&gt;-0     [047] d.h.   635.654296: opal_exit: opcode=0 retval=0
  kopald-1209  [019] d...   636.420943: opal_entry: opcode=10
  kopald-1209  [019] d...   636.420959: opal_exit: opcode=0 retval=0

This is because we incorrectly load the opcode into r0 before calling
__trace_opal_exit(), whereas it expects the opcode in r3 (first function
parameter). In fact we are leaving the retval in r3, so opcode and
retval will always show the same value.

Instead load the opcode into r3, resulting in:

  &lt;idle&gt;-0     [040] d.h.   636.618625: opal_entry: opcode=63
  &lt;idle&gt;-0     [040] d.h.   636.618627: opal_exit: opcode=63 retval=0

Fixes: c49f63530bb6 ("powernv: Add OPAL tracepoints")
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a7e0fb6c2029a780444d09560f739e020d54fe4d ]

Currently the opal_exit tracepoint usually shows the opcode as 0:

  &lt;idle&gt;-0     [047] d.h.   635.654292: opal_entry: opcode=63
  &lt;idle&gt;-0     [047] d.h.   635.654296: opal_exit: opcode=0 retval=0
  kopald-1209  [019] d...   636.420943: opal_entry: opcode=10
  kopald-1209  [019] d...   636.420959: opal_exit: opcode=0 retval=0

This is because we incorrectly load the opcode into r0 before calling
__trace_opal_exit(), whereas it expects the opcode in r3 (first function
parameter). In fact we are leaving the retval in r3, so opcode and
retval will always show the same value.

Instead load the opcode into r3, resulting in:

  &lt;idle&gt;-0     [040] d.h.   636.618625: opal_entry: opcode=63
  &lt;idle&gt;-0     [040] d.h.   636.618627: opal_exit: opcode=63 retval=0

Fixes: c49f63530bb6 ("powernv: Add OPAL tracepoints")
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace/x86: Fix triple fault with graph tracing and suspend-to-ram</title>
<updated>2017-06-13T13:29:19+00:00</updated>
<author>
<name>Josh Poimboeuf</name>
<email>jpoimboe@redhat.com</email>
</author>
<published>2017-04-13T22:53:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=11d54db42149cd7270469c4ff5a9eab9bb7f6bc5'/>
<id>11d54db42149cd7270469c4ff5a9eab9bb7f6bc5</id>
<content type='text'>
[ Upstream commit 34a477e5297cbaa6ecc6e17c042a866e1cbe80d6 ]

On x86-32, with CONFIG_FIRMWARE and multiple CPUs, if you enable function
graph tracing and then suspend to RAM, it will triple fault and reboot when
it resumes.

The first fault happens when booting a secondary CPU:

startup_32_smp()
  load_ucode_ap()
    prepare_ftrace_return()
      ftrace_graph_is_dead()
        (accesses 'kill_ftrace_graph')

The early head_32.S code calls into load_ucode_ap(), which has an an
ftrace hook, so it calls prepare_ftrace_return(), which calls
ftrace_graph_is_dead(), which tries to access the global
'kill_ftrace_graph' variable with a virtual address, causing a fault
because the CPU is still in real mode.

The fix is to add a check in prepare_ftrace_return() to make sure it's
running in protected mode before continuing.  The check makes sure the
stack pointer is a virtual kernel address.  It's a bit of a hack, but
it's not very intrusive and it works well enough.

For reference, here are a few other (more difficult) ways this could
have potentially been fixed:

- Move startup_32_smp()'s call to load_ucode_ap() down to *after* paging
  is enabled.  (No idea what that would break.)

- Track down load_ucode_ap()'s entire callee tree and mark all the
  functions 'notrace'.  (Probably not realistic.)

- Pause graph tracing in ftrace_suspend_notifier_call() or bringup_cpu()
  or __cpu_up(), and ensure that the pause facility can be queried from
  real mode.

Reported-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Tested-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Reviewed-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: "Rafael J . Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: linux-acpi@vger.kernel.org
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: stable@kernel.org
Cc: Len Brown &lt;lenb@kernel.org&gt;
Link: http://lkml.kernel.org/r/5c1272269a580660703ed2eccf44308e790c7a98.1492123841.git.jpoimboe@redhat.com
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 34a477e5297cbaa6ecc6e17c042a866e1cbe80d6 ]

On x86-32, with CONFIG_FIRMWARE and multiple CPUs, if you enable function
graph tracing and then suspend to RAM, it will triple fault and reboot when
it resumes.

The first fault happens when booting a secondary CPU:

startup_32_smp()
  load_ucode_ap()
    prepare_ftrace_return()
      ftrace_graph_is_dead()
        (accesses 'kill_ftrace_graph')

The early head_32.S code calls into load_ucode_ap(), which has an an
ftrace hook, so it calls prepare_ftrace_return(), which calls
ftrace_graph_is_dead(), which tries to access the global
'kill_ftrace_graph' variable with a virtual address, causing a fault
because the CPU is still in real mode.

The fix is to add a check in prepare_ftrace_return() to make sure it's
running in protected mode before continuing.  The check makes sure the
stack pointer is a virtual kernel address.  It's a bit of a hack, but
it's not very intrusive and it works well enough.

For reference, here are a few other (more difficult) ways this could
have potentially been fixed:

- Move startup_32_smp()'s call to load_ucode_ap() down to *after* paging
  is enabled.  (No idea what that would break.)

- Track down load_ucode_ap()'s entire callee tree and mark all the
  functions 'notrace'.  (Probably not realistic.)

- Pause graph tracing in ftrace_suspend_notifier_call() or bringup_cpu()
  or __cpu_up(), and ensure that the pause facility can be queried from
  real mode.

Reported-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Tested-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Reviewed-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: "Rafael J . Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: linux-acpi@vger.kernel.org
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: stable@kernel.org
Cc: Len Brown &lt;lenb@kernel.org&gt;
Link: http://lkml.kernel.org/r/5c1272269a580660703ed2eccf44308e790c7a98.1492123841.git.jpoimboe@redhat.com
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sparc64: Fix kernel panic due to erroneous #ifdef surrounding pmd_write()</title>
<updated>2017-06-13T13:29:18+00:00</updated>
<author>
<name>Tom Hromatka</name>
<email>tom.hromatka@oracle.com</email>
</author>
<published>2017-03-31T22:31:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9ffb20a699469e8de9c44e61b28d0b70354127a4'/>
<id>9ffb20a699469e8de9c44e61b28d0b70354127a4</id>
<content type='text'>
[ Upstream commit 9ae34dbd8afd790cb5f52467e4f816434379eafa ]

This commit moves sparc64's prototype of pmd_write() outside
of the CONFIG_TRANSPARENT_HUGEPAGE ifdef.

In 2013, commit a7b9403f0e6d ("sparc64: Encode huge PMDs using PTE
encoding.") exposed a path where pmd_write() could be called without
CONFIG_TRANSPARENT_HUGEPAGE defined.  This can result in the panic below.

The diff is awkward to read, but the changes are straightforward.
pmd_write() was moved outside of #ifdef CONFIG_TRANSPARENT_HUGEPAGE.
Also, __HAVE_ARCH_PMD_WRITE was defined.

kernel BUG at include/asm-generic/pgtable.h:576!
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
oracle_8114_cdb(8114): Kernel bad sw trap 5 [#1]
CPU: 120 PID: 8114 Comm: oracle_8114_cdb Not tainted
4.1.12-61.7.1.el6uek.rc1.sparc64 #1
task: fff8400700a24d60 ti: fff8400700bc4000 task.ti: fff8400700bc4000
TSTATE: 0000004411e01607 TPC: 00000000004609f8 TNPC: 00000000004609fc Y:
00000005    Not tainted
TPC: &lt;gup_huge_pmd+0x198/0x1e0&gt;
g0: 000000000001c000 g1: 0000000000ef3954 g2: 0000000000000000 g3: 0000000000000001
g4: fff8400700a24d60 g5: fff8001fa5c10000 g6: fff8400700bc4000 g7: 0000000000000720
o0: 0000000000bc5058 o1: 0000000000000240 o2: 0000000000006000 o3: 0000000000001c00
o4: 0000000000000000 o5: 0000048000080000 sp: fff8400700bc6ab1 ret_pc: 00000000004609f0
RPC: &lt;gup_huge_pmd+0x190/0x1e0&gt;
l0: fff8400700bc74fc l1: 0000000000020000 l2: 0000000000002000 l3: 0000000000000000
l4: fff8001f93250950 l5: 000000000113f800 l6: 0000000000000004 l7: 0000000000000000
i0: fff8400700ca46a0 i1: bd0000085e800453 i2: 000000026a0c4000 i3: 000000026a0c6000
i4: 0000000000000001 i5: fff800070c958de8 i6: fff8400700bc6b61 i7: 0000000000460dd0
I7: &lt;gup_pud_range+0x170/0x1a0&gt;
Call Trace:
 [0000000000460dd0] gup_pud_range+0x170/0x1a0
 [0000000000460e84] get_user_pages_fast+0x84/0x120
 [00000000006f5a18] iov_iter_get_pages+0x98/0x240
 [00000000005fa744] do_direct_IO+0xf64/0x1e00
 [00000000005fbbc0] __blockdev_direct_IO+0x360/0x15a0
 [00000000101f74fc] ext4_ind_direct_IO+0xdc/0x400 [ext4]
 [00000000101af690] ext4_ext_direct_IO+0x1d0/0x2c0 [ext4]
 [00000000101af86c] ext4_direct_IO+0xec/0x220 [ext4]
 [0000000000553bd4] generic_file_read_iter+0x114/0x140
 [00000000005bdc2c] __vfs_read+0xac/0x100
 [00000000005bf254] vfs_read+0x54/0x100
 [00000000005bf368] SyS_pread64+0x68/0x80

Signed-off-by: Tom Hromatka &lt;tom.hromatka@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9ae34dbd8afd790cb5f52467e4f816434379eafa ]

This commit moves sparc64's prototype of pmd_write() outside
of the CONFIG_TRANSPARENT_HUGEPAGE ifdef.

In 2013, commit a7b9403f0e6d ("sparc64: Encode huge PMDs using PTE
encoding.") exposed a path where pmd_write() could be called without
CONFIG_TRANSPARENT_HUGEPAGE defined.  This can result in the panic below.

The diff is awkward to read, but the changes are straightforward.
pmd_write() was moved outside of #ifdef CONFIG_TRANSPARENT_HUGEPAGE.
Also, __HAVE_ARCH_PMD_WRITE was defined.

kernel BUG at include/asm-generic/pgtable.h:576!
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
oracle_8114_cdb(8114): Kernel bad sw trap 5 [#1]
CPU: 120 PID: 8114 Comm: oracle_8114_cdb Not tainted
4.1.12-61.7.1.el6uek.rc1.sparc64 #1
task: fff8400700a24d60 ti: fff8400700bc4000 task.ti: fff8400700bc4000
TSTATE: 0000004411e01607 TPC: 00000000004609f8 TNPC: 00000000004609fc Y:
00000005    Not tainted
TPC: &lt;gup_huge_pmd+0x198/0x1e0&gt;
g0: 000000000001c000 g1: 0000000000ef3954 g2: 0000000000000000 g3: 0000000000000001
g4: fff8400700a24d60 g5: fff8001fa5c10000 g6: fff8400700bc4000 g7: 0000000000000720
o0: 0000000000bc5058 o1: 0000000000000240 o2: 0000000000006000 o3: 0000000000001c00
o4: 0000000000000000 o5: 0000048000080000 sp: fff8400700bc6ab1 ret_pc: 00000000004609f0
RPC: &lt;gup_huge_pmd+0x190/0x1e0&gt;
l0: fff8400700bc74fc l1: 0000000000020000 l2: 0000000000002000 l3: 0000000000000000
l4: fff8001f93250950 l5: 000000000113f800 l6: 0000000000000004 l7: 0000000000000000
i0: fff8400700ca46a0 i1: bd0000085e800453 i2: 000000026a0c4000 i3: 000000026a0c6000
i4: 0000000000000001 i5: fff800070c958de8 i6: fff8400700bc6b61 i7: 0000000000460dd0
I7: &lt;gup_pud_range+0x170/0x1a0&gt;
Call Trace:
 [0000000000460dd0] gup_pud_range+0x170/0x1a0
 [0000000000460e84] get_user_pages_fast+0x84/0x120
 [00000000006f5a18] iov_iter_get_pages+0x98/0x240
 [00000000005fa744] do_direct_IO+0xf64/0x1e00
 [00000000005fbbc0] __blockdev_direct_IO+0x360/0x15a0
 [00000000101f74fc] ext4_ind_direct_IO+0xdc/0x400 [ext4]
 [00000000101af690] ext4_ext_direct_IO+0x1d0/0x2c0 [ext4]
 [00000000101af86c] ext4_direct_IO+0xec/0x220 [ext4]
 [0000000000553bd4] generic_file_read_iter+0x114/0x140
 [00000000005bdc2c] __vfs_read+0xac/0x100
 [00000000005bf254] vfs_read+0x54/0x100
 [00000000005bf368] SyS_pread64+0x68/0x80

Signed-off-by: Tom Hromatka &lt;tom.hromatka@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
