<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch, branch v4.4.108</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>alpha: fix build failures</title>
<updated>2017-12-25T13:22:16+00:00</updated>
<author>
<name>Sudip Mukherjee</name>
<email>sudipm.mukherjee@gmail.com</email>
</author>
<published>2017-10-03T23:14:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1cfeaadfd1b45388f8b957cb58d8df3cb1e5509c'/>
<id>1cfeaadfd1b45388f8b957cb58d8df3cb1e5509c</id>
<content type='text'>
commit 8ee912dab95f1483156b6e994004bfcc3158d798 upstream.

The build of alpha allmodconfig is giving error:

  arch/alpha/include/asm/mmu_context.h: In function 'ev5_switch_mm':
  arch/alpha/include/asm/mmu_context.h:160:2: error:
	implicit declaration of function 'task_thread_info';
	did you mean 'init_thread_info'? [-Werror=implicit-function-declaration]

The file 'mmu_context.h' needed an extra header file.

Link: http://lkml.kernel.org/r/1505668810-7497-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&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;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8ee912dab95f1483156b6e994004bfcc3158d798 upstream.

The build of alpha allmodconfig is giving error:

  arch/alpha/include/asm/mmu_context.h: In function 'ev5_switch_mm':
  arch/alpha/include/asm/mmu_context.h:160:2: error:
	implicit declaration of function 'task_thread_info';
	did you mean 'init_thread_info'? [-Werror=implicit-function-declaration]

The file 'mmu_context.h' needed an extra header file.

Link: http://lkml.kernel.org/r/1505668810-7497-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee &lt;sudipm.mukherjee@gmail.com&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;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: math-emu: Fix final emulation phase for certain instructions</title>
<updated>2017-12-25T13:22:15+00:00</updated>
<author>
<name>Aleksandar Markovic</name>
<email>aleksandar.markovic@mips.com</email>
</author>
<published>2017-11-02T11:13:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9c631278a9c6eadebadcd4ee6efbb4edfe2f1c61'/>
<id>9c631278a9c6eadebadcd4ee6efbb4edfe2f1c61</id>
<content type='text'>
commit 409fcace9963c1e8d2cb0f7ac62e8b34d47ef979 upstream.

Fix final phase of &lt;CLASS|MADDF|MSUBF|MAX|MIN|MAXA|MINA&gt;.&lt;D|S&gt;
emulation. Provide proper generation of SIGFPE signal and updating
debugfs FP exception stats in cases of any exception flags set in
preceding phases of emulation.

CLASS.&lt;D|S&gt; instruction may generate "Unimplemented Operation" FP
exception. &lt;MADDF|MSUBF&gt;.&lt;D|S&gt; instructions may generate "Inexact",
"Unimplemented Operation", "Invalid Operation", "Overflow", and
"Underflow" FP exceptions. &lt;MAX|MIN|MAXA|MINA&gt;.&lt;D|S&gt; instructions
can generate "Unimplemented Operation" and "Invalid Operation" FP
exceptions.

The proper final processing of the cases when any FP exception
flag is set is achieved by replacing "break" statement with "goto
copcsr" statement. With such solution, this patch brings the final
phase of emulation of the above instructions consistent with the
one corresponding to the previously implemented emulation of other
related FPU instructions (ADD, SUB, etc.).

Fixes: 38db37ba069f ("MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction")
Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction")
Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction")
Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")
Signed-off-by: Aleksandar Markovic &lt;aleksandar.markovic@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Douglas Leung &lt;douglas.leung@mips.com&gt;
Cc: Goran Ferenc &lt;goran.ferenc@mips.com&gt;
Cc: "Maciej W. Rozycki" &lt;macro@imgtec.com&gt;
Cc: Miodrag Dinic &lt;miodrag.dinic@mips.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Petar Jovanovic &lt;petar.jovanovic@mips.com&gt;
Cc: Raghu Gandham &lt;raghu.gandham@mips.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17581/
Signed-off-by: James Hogan &lt;jhogan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 409fcace9963c1e8d2cb0f7ac62e8b34d47ef979 upstream.

Fix final phase of &lt;CLASS|MADDF|MSUBF|MAX|MIN|MAXA|MINA&gt;.&lt;D|S&gt;
emulation. Provide proper generation of SIGFPE signal and updating
debugfs FP exception stats in cases of any exception flags set in
preceding phases of emulation.

CLASS.&lt;D|S&gt; instruction may generate "Unimplemented Operation" FP
exception. &lt;MADDF|MSUBF&gt;.&lt;D|S&gt; instructions may generate "Inexact",
"Unimplemented Operation", "Invalid Operation", "Overflow", and
"Underflow" FP exceptions. &lt;MAX|MIN|MAXA|MINA&gt;.&lt;D|S&gt; instructions
can generate "Unimplemented Operation" and "Invalid Operation" FP
exceptions.

The proper final processing of the cases when any FP exception
flag is set is achieved by replacing "break" statement with "goto
copcsr" statement. With such solution, this patch brings the final
phase of emulation of the above instructions consistent with the
one corresponding to the previously implemented emulation of other
related FPU instructions (ADD, SUB, etc.).

Fixes: 38db37ba069f ("MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction")
Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction")
Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction")
Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")
Signed-off-by: Aleksandar Markovic &lt;aleksandar.markovic@mips.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Douglas Leung &lt;douglas.leung@mips.com&gt;
Cc: Goran Ferenc &lt;goran.ferenc@mips.com&gt;
Cc: "Maciej W. Rozycki" &lt;macro@imgtec.com&gt;
Cc: Miodrag Dinic &lt;miodrag.dinic@mips.com&gt;
Cc: Paul Burton &lt;paul.burton@mips.com&gt;
Cc: Petar Jovanovic &lt;petar.jovanovic@mips.com&gt;
Cc: Raghu Gandham &lt;raghu.gandham@mips.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17581/
Signed-off-by: James Hogan &lt;jhogan@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: dma-mapping: disallow dma_get_sgtable() for non-kernel managed memory</title>
<updated>2017-12-25T13:22:13+00:00</updated>
<author>
<name>Russell King</name>
<email>rmk+kernel@armlinux.org.uk</email>
</author>
<published>2017-03-29T16:12:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1779b33294dab3e3a08afa5196d01848acfbe40c'/>
<id>1779b33294dab3e3a08afa5196d01848acfbe40c</id>
<content type='text'>
[ Upstream commit 916a008b4b8ecc02fbd035cfb133773dba1ff3d7 ]

dma_get_sgtable() tries to create a scatterlist table containing valid
struct page pointers for the coherent memory allocation passed in to it.

However, memory can be declared via dma_declare_coherent_memory(), or
via other reservation schemes which means that coherent memory is not
guaranteed to be backed by struct pages.  In such cases, the resulting
scatterlist table contains pointers to invalid pages, which causes
kernel oops later.

This patch adds detection of such memory, and refuses to create a
scatterlist table for such memory.

Reported-by: Shuah Khan &lt;shuahkhan@gmail.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 916a008b4b8ecc02fbd035cfb133773dba1ff3d7 ]

dma_get_sgtable() tries to create a scatterlist table containing valid
struct page pointers for the coherent memory allocation passed in to it.

However, memory can be declared via dma_declare_coherent_memory(), or
via other reservation schemes which means that coherent memory is not
guaranteed to be backed by struct pages.  In such cases, the resulting
scatterlist table contains pointers to invalid pages, which causes
kernel oops later.

This patch adds detection of such memory, and refuses to create a
scatterlist table for such memory.

Reported-by: Shuah Khan &lt;shuahkhan@gmail.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@armlinux.org.uk&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: dts: am335x-evmsk: adjust mmc2 param to allow suspend</title>
<updated>2017-12-25T13:22:13+00:00</updated>
<author>
<name>Reizer, Eyal</name>
<email>eyalr@ti.com</email>
</author>
<published>2017-03-26T08:53:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=27c2fa1ae0ea735b32376777f012ab92c4ee8650'/>
<id>27c2fa1ae0ea735b32376777f012ab92c4ee8650</id>
<content type='text'>
[ Upstream commit 9bcf53f34a2c1cebc45cc12e273dcd5f51fbc099 ]

mmc2 used for wl12xx was missing the keep-power-in suspend
parameter. As a result the board couldn't reach suspend state.

Signed-off-by: Eyal Reizer &lt;eyalr@ti.com&gt;
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9bcf53f34a2c1cebc45cc12e273dcd5f51fbc099 ]

mmc2 used for wl12xx was missing the keep-power-in suspend
parameter. As a result the board couldn't reach suspend state.

Signed-off-by: Eyal Reizer &lt;eyalr@ti.com&gt;
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: dts: ti: fix PCI bus dtc warnings</title>
<updated>2017-12-25T13:22:11+00:00</updated>
<author>
<name>Rob Herring</name>
<email>robh@kernel.org</email>
</author>
<published>2017-03-22T02:03:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2e114c7b45625f6db6a30529f5d89b1b8dd0a367'/>
<id>2e114c7b45625f6db6a30529f5d89b1b8dd0a367</id>
<content type='text'>
[ Upstream commit 7d79f6098d82f8c09914d7799bc96891ad9c3baf ]

dtc recently added PCI bus checks. Fix these warnings.

Signed-off-by: Rob Herring &lt;robh@kernel.org&gt;
Cc: "Benoît Cousson" &lt;bcousson@baylibre.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Cc: linux-omap@vger.kernel.org
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7d79f6098d82f8c09914d7799bc96891ad9c3baf ]

dtc recently added PCI bus checks. Fix these warnings.

Signed-off-by: Rob Herring &lt;robh@kernel.org&gt;
Cc: "Benoît Cousson" &lt;bcousson@baylibre.com&gt;
Cc: Tony Lindgren &lt;tony@atomide.com&gt;
Cc: linux-omap@vger.kernel.org
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: VMX: Fix enable VPID conditions</title>
<updated>2017-12-25T13:22:11+00:00</updated>
<author>
<name>Wanpeng Li</name>
<email>wanpeng.li@hotmail.com</email>
</author>
<published>2017-03-23T12:30:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f1fdf68b4f947be85d96ac835d86bbf063b454b4'/>
<id>f1fdf68b4f947be85d96ac835d86bbf063b454b4</id>
<content type='text'>
[ Upstream commit 08d839c4b134b8328ec42f2157a9ca4b93227c03 ]

This can be reproduced by running L2 on L1, and disable VPID on L0
if w/o commit "KVM: nVMX: Fix nested VPID vmx exec control", the L2
crash as below:

KVM: entry failed, hardware error 0x7
EAX=00000000 EBX=00000000 ECX=00000000 EDX=000306c3
ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000
EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =0000 00000000 0000ffff 00009300
CS =f000 ffff0000 0000ffff 00009b00
SS =0000 00000000 0000ffff 00009300
DS =0000 00000000 0000ffff 00009300
FS =0000 00000000 0000ffff 00009300
GS =0000 00000000 0000ffff 00009300
LDT=0000 00000000 0000ffff 00008200
TR =0000 00000000 0000ffff 00008b00
GDT=     00000000 0000ffff
IDT=     00000000 0000ffff
CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000
DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000
DR6=00000000ffff0ff0 DR7=0000000000000400
EFER=0000000000000000

Reference SDM 30.3 INVVPID:

Protected Mode Exceptions
- #UD
  - If not in VMX operation.
  - If the logical processor does not support VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=0).
  - If the logical processor supports VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=1) but does
    not support the INVVPID instruction (IA32_VMX_EPT_VPID_CAP[32]=0).

So we should check both VPID enable bit in vmx exec control and INVVPID support bit
in vmx capability MSRs to enable VPID. This patch adds the guarantee to not enable
VPID if either INVVPID or single-context/all-context invalidation is not exposed in
vmx capability MSRs.

Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Reviewed-by: Jim Mattson &lt;jmattson@google.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 08d839c4b134b8328ec42f2157a9ca4b93227c03 ]

This can be reproduced by running L2 on L1, and disable VPID on L0
if w/o commit "KVM: nVMX: Fix nested VPID vmx exec control", the L2
crash as below:

KVM: entry failed, hardware error 0x7
EAX=00000000 EBX=00000000 ECX=00000000 EDX=000306c3
ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000
EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =0000 00000000 0000ffff 00009300
CS =f000 ffff0000 0000ffff 00009b00
SS =0000 00000000 0000ffff 00009300
DS =0000 00000000 0000ffff 00009300
FS =0000 00000000 0000ffff 00009300
GS =0000 00000000 0000ffff 00009300
LDT=0000 00000000 0000ffff 00008200
TR =0000 00000000 0000ffff 00008b00
GDT=     00000000 0000ffff
IDT=     00000000 0000ffff
CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000
DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000
DR6=00000000ffff0ff0 DR7=0000000000000400
EFER=0000000000000000

Reference SDM 30.3 INVVPID:

Protected Mode Exceptions
- #UD
  - If not in VMX operation.
  - If the logical processor does not support VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=0).
  - If the logical processor supports VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=1) but does
    not support the INVVPID instruction (IA32_VMX_EPT_VPID_CAP[32]=0).

So we should check both VPID enable bit in vmx exec control and INVVPID support bit
in vmx capability MSRs to enable VPID. This patch adds the guarantee to not enable
VPID if either INVVPID or single-context/all-context invalidation is not exposed in
vmx capability MSRs.

Reviewed-by: David Hildenbrand &lt;david@redhat.com&gt;
Reviewed-by: Jim Mattson &lt;jmattson@google.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: x86: correct async page present tracepoint</title>
<updated>2017-12-25T13:22:11+00:00</updated>
<author>
<name>Wanpeng Li</name>
<email>wanpeng.li@hotmail.com</email>
</author>
<published>2017-03-21T04:18:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=caa4cfd173b76b0b4a9ae894d438980daa235016'/>
<id>caa4cfd173b76b0b4a9ae894d438980daa235016</id>
<content type='text'>
[ Upstream commit 24dccf83a121b8a4ad5c2ad383a8184ef6c266ee ]

After async pf setup successfully, there is a broadcast wakeup w/ special
token 0xffffffff which tells vCPU that it should wake up all processes
waiting for APFs though there is no real process waiting at the moment.

The async page present tracepoint print prematurely and fails to catch the
special token setup. This patch fixes it by moving the async page present
tracepoint after the special token setup.

Before patch:

qemu-system-x86-8499  [006] ...1  5973.473292: kvm_async_pf_ready: token 0x0 gva 0x0

After patch:

qemu-system-x86-8499  [006] ...1  5973.473292: kvm_async_pf_ready: token 0xffffffff gva 0x0

Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 24dccf83a121b8a4ad5c2ad383a8184ef6c266ee ]

After async pf setup successfully, there is a broadcast wakeup w/ special
token 0xffffffff which tells vCPU that it should wake up all processes
waiting for APFs though there is no real process waiting at the moment.

The async page present tracepoint print prematurely and fails to catch the
special token setup. This patch fixes it by moving the async page present
tracepoint after the special token setup.

Before patch:

qemu-system-x86-8499  [006] ...1  5973.473292: kvm_async_pf_ready: token 0x0 gva 0x0

After patch:

qemu-system-x86-8499  [006] ...1  5973.473292: kvm_async_pf_ready: token 0xffffffff gva 0x0

Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm: kprobes: Align stack to 8-bytes in test code</title>
<updated>2017-12-25T13:22:10+00:00</updated>
<author>
<name>Jon Medhurst</name>
<email>tixy@linaro.org</email>
</author>
<published>2017-03-02T13:04:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a23a447e47ccb333a392e9e132c231be0d5953db'/>
<id>a23a447e47ccb333a392e9e132c231be0d5953db</id>
<content type='text'>
[ Upstream commit 974310d047f3c7788a51d10c8d255eebdb1fa857 ]

kprobes test cases need to have a stack that is aligned to an 8-byte
boundary because they call other functions (and the ARM ABI mandates
that alignment) and because test cases include 64-bit accesses to the
stack. Unfortunately, GCC doesn't ensure this alignment for inline
assembler and for the code in question seems to always misalign it by
pushing just the LR register onto the stack. We therefore need to
explicitly perform stack alignment at the start of each test case.

Without this fix, some test cases will generate alignment faults on
systems where alignment is enforced. Even if the kernel is configured to
handle these faults in software, triggering them is ugly. It also
exposes limitations in the fault handling code which doesn't cope with
writes to the stack. E.g. when handling this instruction

   strd r6, [sp, #-64]!

the fault handling code will write to a stack location below the SP
value at the point the fault occurred, which coincides with where the
exception handler has pushed the saved register context. This results in
corruption of those registers.

Signed-off-by: Jon Medhurst &lt;tixy@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 974310d047f3c7788a51d10c8d255eebdb1fa857 ]

kprobes test cases need to have a stack that is aligned to an 8-byte
boundary because they call other functions (and the ARM ABI mandates
that alignment) and because test cases include 64-bit accesses to the
stack. Unfortunately, GCC doesn't ensure this alignment for inline
assembler and for the code in question seems to always misalign it by
pushing just the LR register onto the stack. We therefore need to
explicitly perform stack alignment at the start of each test case.

Without this fix, some test cases will generate alignment faults on
systems where alignment is enforced. Even if the kernel is configured to
handle these faults in software, triggering them is ugly. It also
exposes limitations in the fault handling code which doesn't cope with
writes to the stack. E.g. when handling this instruction

   strd r6, [sp, #-64]!

the fault handling code will write to a stack location below the SP
value at the point the fault occurred, which coincides with where the
exception handler has pushed the saved register context. This results in
corruption of those registers.

Signed-off-by: Jon Medhurst &lt;tixy@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm: kprobes: Fix the return address of multiple kretprobes</title>
<updated>2017-12-25T13:22:10+00:00</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2017-02-13T15:05:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3f7855a522228787e2f73c279d7c0a3a6d3a2323'/>
<id>3f7855a522228787e2f73c279d7c0a3a6d3a2323</id>
<content type='text'>
[ Upstream commit 06553175f585b52509c7df37d6f4a50aacb7b211 ]

This is arm port of commit 737480a0d525 ("kprobes/x86:
Fix the return address of multiple kretprobes").

Fix the return address of subsequent kretprobes when multiple
kretprobes are set on the same function.

For example:

  # cd /sys/kernel/debug/tracing
  # echo "r:event1 sys_symlink" &gt; kprobe_events
  # echo "r:event2 sys_symlink" &gt;&gt; kprobe_events
  # echo 1 &gt; events/kprobes/enable
  # ln -s /tmp/foo /tmp/bar

 (without this patch)

  # cat trace | grep -v ^#
              ln-82    [000] dn.2    68.446525: event1: (kretprobe_trampoline+0x0/0x18 &lt;- SyS_symlink)
              ln-82    [000] dn.2    68.447831: event2: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)

 (with this patch)

  # cat trace | grep -v ^#
              ln-81    [000] dn.1    39.463469: event1: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)
              ln-81    [000] dn.1    39.464701: event2: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: KUMANO Syuhei &lt;kumano.prog@gmail.com&gt;
Signed-off-by: Jon Medhurst &lt;tixy@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 06553175f585b52509c7df37d6f4a50aacb7b211 ]

This is arm port of commit 737480a0d525 ("kprobes/x86:
Fix the return address of multiple kretprobes").

Fix the return address of subsequent kretprobes when multiple
kretprobes are set on the same function.

For example:

  # cd /sys/kernel/debug/tracing
  # echo "r:event1 sys_symlink" &gt; kprobe_events
  # echo "r:event2 sys_symlink" &gt;&gt; kprobe_events
  # echo 1 &gt; events/kprobes/enable
  # ln -s /tmp/foo /tmp/bar

 (without this patch)

  # cat trace | grep -v ^#
              ln-82    [000] dn.2    68.446525: event1: (kretprobe_trampoline+0x0/0x18 &lt;- SyS_symlink)
              ln-82    [000] dn.2    68.447831: event2: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)

 (with this patch)

  # cat trace | grep -v ^#
              ln-81    [000] dn.1    39.463469: event1: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)
              ln-81    [000] dn.1    39.464701: event2: (ret_fast_syscall+0x0/0x1c &lt;- SyS_symlink)

Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: KUMANO Syuhei &lt;kumano.prog@gmail.com&gt;
Signed-off-by: Jon Medhurst &lt;tixy@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@verizon.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/irq: Do not substract irq_tlb_count from irq_call_count</title>
<updated>2017-12-25T13:22:09+00:00</updated>
<author>
<name>Aaron Lu</name>
<email>aaron.lu@intel.com</email>
</author>
<published>2016-08-11T07:44:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3b9d9ec0d8261bb9b12f858e66f0c84cd2a6a3bb'/>
<id>3b9d9ec0d8261bb9b12f858e66f0c84cd2a6a3bb</id>
<content type='text'>
commit 82ba4faca1bffad429f15c90c980ffd010366c25 upstream.

Since commit:

  52aec3308db8 ("x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR")

the TLB remote shootdown is done through call function vector. That
commit didn't take care of irq_tlb_count, which a later commit:

  fd0f5869724f ("x86: Distinguish TLB shootdown interrupts from other functions call interrupts")

... tried to fix.

The fix assumes every increase of irq_tlb_count has a corresponding
increase of irq_call_count. So the irq_call_count is always bigger than
irq_tlb_count and we could substract irq_tlb_count from irq_call_count.

Unfortunately this is not true for the smp_call_function_single() case.
The IPI is only sent if the target CPU's call_single_queue is empty when
adding a csd into it in generic_exec_single. That means if two threads
are both adding flush tlb csds to the same CPU's call_single_queue, only
one IPI is sent. In other words, the irq_call_count is incremented by 1
but irq_tlb_count is incremented by 2. Over time, irq_tlb_count will be
bigger than irq_call_count and the substract will produce a very large
irq_call_count value due to overflow.

Considering that:

  1) it's not worth to send more IPIs for the sake of accurate counting of
     irq_call_count in generic_exec_single();

  2) it's not easy to tell if the call function interrupt is for TLB
     shootdown in __smp_call_function_single_interrupt().

Not to exclude TLB shootdown from call function count seems to be the
simplest fix and this patch just does that.

This bug was found by LKP's cyclic performance regression tracking recently
with the vm-scalability test suite. I have bisected to commit:

  3dec0ba0be6a ("mm/rmap: share the i_mmap_rwsem")

This commit didn't do anything wrong but revealed the irq_call_count
problem. IIUC, the commit makes rwc-&gt;remap_one in rmap_walk_file
concurrent with multiple threads.  When remap_one is try_to_unmap_one(),
then multiple threads could queue flush TLB to the same CPU but only
one IPI will be sent.

Since the commit was added in Linux v3.19, the counting problem only
shows up from v3.19 onwards.

Signed-off-by: Aaron Lu &lt;aaron.lu@intel.com&gt;
Cc: Alex Shi &lt;alex.shi@linaro.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Huang Ying &lt;ying.huang@intel.com&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.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;
Cc: Tomoki Sekiyama &lt;tomoki.sekiyama.qu@hitachi.com&gt;
Link: http://lkml.kernel.org/r/20160811074430.GA18163@aaronlu.sh.intel.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 82ba4faca1bffad429f15c90c980ffd010366c25 upstream.

Since commit:

  52aec3308db8 ("x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR")

the TLB remote shootdown is done through call function vector. That
commit didn't take care of irq_tlb_count, which a later commit:

  fd0f5869724f ("x86: Distinguish TLB shootdown interrupts from other functions call interrupts")

... tried to fix.

The fix assumes every increase of irq_tlb_count has a corresponding
increase of irq_call_count. So the irq_call_count is always bigger than
irq_tlb_count and we could substract irq_tlb_count from irq_call_count.

Unfortunately this is not true for the smp_call_function_single() case.
The IPI is only sent if the target CPU's call_single_queue is empty when
adding a csd into it in generic_exec_single. That means if two threads
are both adding flush tlb csds to the same CPU's call_single_queue, only
one IPI is sent. In other words, the irq_call_count is incremented by 1
but irq_tlb_count is incremented by 2. Over time, irq_tlb_count will be
bigger than irq_call_count and the substract will produce a very large
irq_call_count value due to overflow.

Considering that:

  1) it's not worth to send more IPIs for the sake of accurate counting of
     irq_call_count in generic_exec_single();

  2) it's not easy to tell if the call function interrupt is for TLB
     shootdown in __smp_call_function_single_interrupt().

Not to exclude TLB shootdown from call function count seems to be the
simplest fix and this patch just does that.

This bug was found by LKP's cyclic performance regression tracking recently
with the vm-scalability test suite. I have bisected to commit:

  3dec0ba0be6a ("mm/rmap: share the i_mmap_rwsem")

This commit didn't do anything wrong but revealed the irq_call_count
problem. IIUC, the commit makes rwc-&gt;remap_one in rmap_walk_file
concurrent with multiple threads.  When remap_one is try_to_unmap_one(),
then multiple threads could queue flush TLB to the same CPU but only
one IPI will be sent.

Since the commit was added in Linux v3.19, the counting problem only
shows up from v3.19 onwards.

Signed-off-by: Aaron Lu &lt;aaron.lu@intel.com&gt;
Cc: Alex Shi &lt;alex.shi@linaro.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Huang Ying &lt;ying.huang@intel.com&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@redhat.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;
Cc: Tomoki Sekiyama &lt;tomoki.sekiyama.qu@hitachi.com&gt;
Link: http://lkml.kernel.org/r/20160811074430.GA18163@aaronlu.sh.intel.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
