<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/powerpc/lib, branch vsnprintf</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2024-11-23T18:44:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-11-23T18:44:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=42d9e8b7ccddee75989283cf7477305cfe3776ff'/>
<id>42d9e8b7ccddee75989283cf7477305cfe3776ff</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Rework kfence support for the HPT MMU to work on systems with &gt;= 16TB
   of RAM.

 - Remove the powerpc "maple" platform, used by the "Yellow Dog
   Powerstation".

 - Add support for DYNAMIC_FTRACE_WITH_CALL_OPS,
   DYNAMIC_FTRACE_WITH_DIRECT_CALLS &amp; BPF Trampolines.

 - Add support for running KVM nested guests on Power11.

 - Other small features, cleanups and fixes.

Thanks to Amit Machhiwal, Arnd Bergmann, Christophe Leroy, Costa
Shulyupin, David Hunter, David Wang, Disha Goel, Gautam Menghani, Geert
Uytterhoeven, Hari Bathini, Julia Lawall, Kajol Jain, Keith Packard,
Lukas Bulwahn, Madhavan Srinivasan, Markus Elfring, Michal Suchanek,
Ming Lei, Mukesh Kumar Chaurasiya, Nathan Chancellor, Naveen N Rao,
Nicholas Piggin, Nysal Jan K.A, Paulo Miguel Almeida, Pavithra Prakash,
Ritesh Harjani (IBM), Rob Herring (Arm), Sachin P Bappalige, Shen
Lichuan, Simon Horman, Sourabh Jain, Thomas Weißschuh, Thorsten Blum,
Thorsten Leemhuis, Venkat Rao Bagalkote, Zhang Zekun, and zhang jiao.

* tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (89 commits)
  EDAC/powerpc: Remove PPC_MAPLE drivers
  powerpc/perf: Add per-task/process monitoring to vpa_pmu driver
  powerpc/kvm: Add vpa latency counters to kvm_vcpu_arch
  docs: ABI: sysfs-bus-event_source-devices-vpa-pmu: Document sysfs event format entries for vpa_pmu
  powerpc/perf: Add perf interface to expose vpa counters
  MAINTAINERS: powerpc: Mark Maddy as "M"
  powerpc/Makefile: Allow overriding CPP
  powerpc-km82xx.c: replace of_node_put() with __free
  ps3: Correct some typos in comments
  powerpc/kexec: Fix return of uninitialized variable
  macintosh: Use common error handling code in via_pmu_led_init()
  powerpc/powermac: Use of_property_match_string() in pmac_has_backlight_type()
  powerpc: remove dead config options for MPC85xx platform support
  powerpc/xive: Use cpumask_intersects()
  selftests/powerpc: Remove the path after initialization.
  powerpc/xmon: symbol lookup length fixed
  powerpc/ep8248e: Use %pa to format resource_size_t
  powerpc/ps3: Reorganize kerneldoc parameter names
  KVM: PPC: Book3S HV: Fix kmv -&gt; kvm typo
  powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:

 - Rework kfence support for the HPT MMU to work on systems with &gt;= 16TB
   of RAM.

 - Remove the powerpc "maple" platform, used by the "Yellow Dog
   Powerstation".

 - Add support for DYNAMIC_FTRACE_WITH_CALL_OPS,
   DYNAMIC_FTRACE_WITH_DIRECT_CALLS &amp; BPF Trampolines.

 - Add support for running KVM nested guests on Power11.

 - Other small features, cleanups and fixes.

Thanks to Amit Machhiwal, Arnd Bergmann, Christophe Leroy, Costa
Shulyupin, David Hunter, David Wang, Disha Goel, Gautam Menghani, Geert
Uytterhoeven, Hari Bathini, Julia Lawall, Kajol Jain, Keith Packard,
Lukas Bulwahn, Madhavan Srinivasan, Markus Elfring, Michal Suchanek,
Ming Lei, Mukesh Kumar Chaurasiya, Nathan Chancellor, Naveen N Rao,
Nicholas Piggin, Nysal Jan K.A, Paulo Miguel Almeida, Pavithra Prakash,
Ritesh Harjani (IBM), Rob Herring (Arm), Sachin P Bappalige, Shen
Lichuan, Simon Horman, Sourabh Jain, Thomas Weißschuh, Thorsten Blum,
Thorsten Leemhuis, Venkat Rao Bagalkote, Zhang Zekun, and zhang jiao.

* tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (89 commits)
  EDAC/powerpc: Remove PPC_MAPLE drivers
  powerpc/perf: Add per-task/process monitoring to vpa_pmu driver
  powerpc/kvm: Add vpa latency counters to kvm_vcpu_arch
  docs: ABI: sysfs-bus-event_source-devices-vpa-pmu: Document sysfs event format entries for vpa_pmu
  powerpc/perf: Add perf interface to expose vpa counters
  MAINTAINERS: powerpc: Mark Maddy as "M"
  powerpc/Makefile: Allow overriding CPP
  powerpc-km82xx.c: replace of_node_put() with __free
  ps3: Correct some typos in comments
  powerpc/kexec: Fix return of uninitialized variable
  macintosh: Use common error handling code in via_pmu_led_init()
  powerpc/powermac: Use of_property_match_string() in pmac_has_backlight_type()
  powerpc: remove dead config options for MPC85xx platform support
  powerpc/xive: Use cpumask_intersects()
  selftests/powerpc: Remove the path after initialization.
  powerpc/xmon: symbol lookup length fixed
  powerpc/ep8248e: Use %pa to format resource_size_t
  powerpc/ps3: Reorganize kerneldoc parameter names
  KVM: PPC: Book3S HV: Fix kmv -&gt; kvm typo
  powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static</title>
<updated>2024-11-14T03:17:36+00:00</updated>
<author>
<name>Michal Suchanek</name>
<email>msuchanek@suse.de</email>
</author>
<published>2024-10-01T13:03:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b'/>
<id>a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b</id>
<content type='text'>
These functions are not used outside of sstep.c

Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek &lt;msuchanek@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
These functions are not used outside of sstep.c

Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek &lt;msuchanek@suse.de&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de

</pre>
</div>
</content>
</entry>
<entry>
<title>asm-generic: introduce text-patching.h</title>
<updated>2024-11-07T22:25:15+00:00</updated>
<author>
<name>Mike Rapoport (Microsoft)</name>
<email>rppt@kernel.org</email>
</author>
<published>2024-10-23T16:27:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0c3beacf681ec897e0b36685a9b49d01f5cb2dfb'/>
<id>0c3beacf681ec897e0b36685a9b49d01f5cb2dfb</id>
<content type='text'>
Several architectures support text patching, but they name the header
files that declare patching functions differently.

Make all such headers consistently named text-patching.h and add an empty
header in asm-generic for architectures that do not support text patching.

Link: https://lkml.kernel.org/r/20241023162711.2579610-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt; # m68k
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Tested-by: kdevops &lt;kdevops@lists.linux.dev&gt;
Cc: Andreas Larsson &lt;andreas@gaisler.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Brian Cain &lt;bcain@quicinc.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Dinh Nguyen &lt;dinguyen@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Huacai Chen &lt;chenhuacai@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: Liam R. Howlett &lt;Liam.Howlett@Oracle.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Song Liu &lt;song@kernel.org&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Uladzislau Rezki (Sony) &lt;urezki@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@kernel.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Several architectures support text patching, but they name the header
files that declare patching functions differently.

Make all such headers consistently named text-patching.h and add an empty
header in asm-generic for architectures that do not support text patching.

Link: https://lkml.kernel.org/r/20241023162711.2579610-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt; # m68k
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Reviewed-by: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Tested-by: kdevops &lt;kdevops@lists.linux.dev&gt;
Cc: Andreas Larsson &lt;andreas@gaisler.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Brian Cain &lt;bcain@quicinc.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Dinh Nguyen &lt;dinguyen@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Huacai Chen &lt;chenhuacai@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Kent Overstreet &lt;kent.overstreet@linux.dev&gt;
Cc: Liam R. Howlett &lt;Liam.Howlett@Oracle.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Song Liu &lt;song@kernel.org&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Suren Baghdasaryan &lt;surenb@google.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Uladzislau Rezki (Sony) &lt;urezki@gmail.com&gt;
Cc: Vineet Gupta &lt;vgupta@kernel.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/vdso32: Fix use of crtsavres for PPC64</title>
<updated>2024-09-20T09:06:19+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2024-09-19T18:55:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=699d53f04829d6b8855ff458f86e4b75ef3e5f0c'/>
<id>699d53f04829d6b8855ff458f86e4b75ef3e5f0c</id>
<content type='text'>
crtsavres.S content is encloded by a #ifndef CONFIG_PPC64

To be used on VDSO32 on PPC64 it's content must available on PPC64 as
well.

Replace #ifndef CONFIG_PPC64 by #ifndef __powerpc64__ as __powerpc64__
is not set when building VDSO32 on PPC64.

Reported-by: Christian Zigotzky &lt;chzigotzky@xenosoft.de&gt;
Closes: https://lore.kernel.org/linuxppc-dev/047b7503-af0c-4bb0-b12a-2f6b1e461752@csgroup.eu/T/
Fixes: b163596a5b6f ("powerpc/vdso32: Add crtsavres")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/aded2b257018fe654db759fdfa4ab1a0b5426b1b.1726772140.git.christophe.leroy@csgroup.eu
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
crtsavres.S content is encloded by a #ifndef CONFIG_PPC64

To be used on VDSO32 on PPC64 it's content must available on PPC64 as
well.

Replace #ifndef CONFIG_PPC64 by #ifndef __powerpc64__ as __powerpc64__
is not set when building VDSO32 on PPC64.

Reported-by: Christian Zigotzky &lt;chzigotzky@xenosoft.de&gt;
Closes: https://lore.kernel.org/linuxppc-dev/047b7503-af0c-4bb0-b12a-2f6b1e461752@csgroup.eu/T/
Fixes: b163596a5b6f ("powerpc/vdso32: Add crtsavres")
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/aded2b257018fe654db759fdfa4ab1a0b5426b1b.1726772140.git.christophe.leroy@csgroup.eu
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2024-09-19T06:03:00+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-09-19T06:03:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3a7101e9b27fe97240c2fd430c71e61262447dd1'/>
<id>3a7101e9b27fe97240c2fd430c71e61262447dd1</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Reduce alignment constraints on STRICT_KERNEL_RWX and speed-up TLB
   misses on 8xx and 603

 - Replace kretprobe code with rethook and enable fprobe

 - Remove the "fast endian switch" syscall

 - Handle DLPAR device tree updates in kernel, allowing the deprecation
   of the binary /proc/powerpc/ofdt interface

Thanks to Abhishek Dubey, Alex Shi, Benjamin Gray, Christophe Leroy,
Gaosheng Cui, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari
Bathini, Huang Xiaojia, Jinjie Ruan, Madhavan Srinivasan, Miguel Ojeda,
Mina Almasry, Narayana Murty N, Naveen Rao, Rob Herring (Arm), Scott
Cheloha, Segher Boessenkool, Stephen Rothwell, Thomas Zimmermann, Uwe
Kleine-König, Vaibhav Jain, and Zhang Zekun.

* tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (59 commits)
  powerpc/atomic: Use YZ constraints for DS-form instructions
  MAINTAINERS: powerpc: Add Maddy
  powerpc: Switch back to struct platform_driver::remove()
  powerpc/pseries/eeh: Fix pseries_eeh_err_inject
  selftests/powerpc: Allow building without static libc
  macintosh/via-pmu: register_pmu_pm_ops() can be __init
  powerpc: Stop using no_llseek
  powerpc/64s: Remove the "fast endian switch" syscall
  powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages
  powerpc/mm/64s: Move THP reqs into a separate symbol
  powerpc/64s: Make mmu_hash_ops __ro_after_init
  powerpc: Replace kretprobe code with rethook on powerpc
  powerpc: pseries: Constify struct kobj_type
  powerpc: powernv: Constify struct kobj_type
  powerpc: Constify struct kobj_type
  powerpc/pseries/dlpar: Add device tree nodes for DLPAR IO add
  powerpc/pseries/dlpar: Remove device tree node for DLPAR IO remove
  powerpc/pseries: Use correct data types from pseries_hp_errorlog struct
  powerpc/vdso: Inconditionally use CFUNC macro
  powerpc/32: Implement validation of emergency stack
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:

 - Reduce alignment constraints on STRICT_KERNEL_RWX and speed-up TLB
   misses on 8xx and 603

 - Replace kretprobe code with rethook and enable fprobe

 - Remove the "fast endian switch" syscall

 - Handle DLPAR device tree updates in kernel, allowing the deprecation
   of the binary /proc/powerpc/ofdt interface

Thanks to Abhishek Dubey, Alex Shi, Benjamin Gray, Christophe Leroy,
Gaosheng Cui, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari
Bathini, Huang Xiaojia, Jinjie Ruan, Madhavan Srinivasan, Miguel Ojeda,
Mina Almasry, Narayana Murty N, Naveen Rao, Rob Herring (Arm), Scott
Cheloha, Segher Boessenkool, Stephen Rothwell, Thomas Zimmermann, Uwe
Kleine-König, Vaibhav Jain, and Zhang Zekun.

* tag 'powerpc-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (59 commits)
  powerpc/atomic: Use YZ constraints for DS-form instructions
  MAINTAINERS: powerpc: Add Maddy
  powerpc: Switch back to struct platform_driver::remove()
  powerpc/pseries/eeh: Fix pseries_eeh_err_inject
  selftests/powerpc: Allow building without static libc
  macintosh/via-pmu: register_pmu_pm_ops() can be __init
  powerpc: Stop using no_llseek
  powerpc/64s: Remove the "fast endian switch" syscall
  powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages
  powerpc/mm/64s: Move THP reqs into a separate symbol
  powerpc/64s: Make mmu_hash_ops __ro_after_init
  powerpc: Replace kretprobe code with rethook on powerpc
  powerpc: pseries: Constify struct kobj_type
  powerpc: powernv: Constify struct kobj_type
  powerpc: Constify struct kobj_type
  powerpc/pseries/dlpar: Add device tree nodes for DLPAR IO add
  powerpc/pseries/dlpar: Remove device tree node for DLPAR IO remove
  powerpc/pseries: Use correct data types from pseries_hp_errorlog struct
  powerpc/vdso: Inconditionally use CFUNC macro
  powerpc/32: Implement validation of emergency stack
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/qspinlock: Fix deadlock in MCS queue</title>
<updated>2024-08-29T05:12:51+00:00</updated>
<author>
<name>Nysal Jan K.A.</name>
<email>nysal@linux.ibm.com</email>
</author>
<published>2024-08-29T02:28:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=734ad0af3609464f8f93e00b6c0de1e112f44559'/>
<id>734ad0af3609464f8f93e00b6c0de1e112f44559</id>
<content type='text'>
If an interrupt occurs in queued_spin_lock_slowpath() after we increment
qnodesp-&gt;count and before node-&gt;lock is initialized, another CPU might
see stale lock values in get_tail_qnode(). If the stale lock value happens
to match the lock on that CPU, then we write to the "next" pointer of
the wrong qnode. This causes a deadlock as the former CPU, once it becomes
the head of the MCS queue, will spin indefinitely until it's "next" pointer
is set by its successor in the queue.

Running stress-ng on a 16 core (16EC/16VP) shared LPAR, results in
occasional lockups similar to the following:

   $ stress-ng --all 128 --vm-bytes 80% --aggressive \
               --maximize --oomable --verify  --syslog \
               --metrics  --times  --timeout 5m

   watchdog: CPU 15 Hard LOCKUP
   ......
   NIP [c0000000000b78f4] queued_spin_lock_slowpath+0x1184/0x1490
   LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90
   Call Trace:
    0xc000002cfffa3bf0 (unreliable)
    _raw_spin_lock+0x6c/0x90
    raw_spin_rq_lock_nested.part.135+0x4c/0xd0
    sched_ttwu_pending+0x60/0x1f0
    __flush_smp_call_function_queue+0x1dc/0x670
    smp_ipi_demux_relaxed+0xa4/0x100
    xive_muxed_ipi_action+0x20/0x40
    __handle_irq_event_percpu+0x80/0x240
    handle_irq_event_percpu+0x2c/0x80
    handle_percpu_irq+0x84/0xd0
    generic_handle_irq+0x54/0x80
    __do_irq+0xac/0x210
    __do_IRQ+0x74/0xd0
    0x0
    do_IRQ+0x8c/0x170
    hardware_interrupt_common_virt+0x29c/0x2a0
   --- interrupt: 500 at queued_spin_lock_slowpath+0x4b8/0x1490
   ......
   NIP [c0000000000b6c28] queued_spin_lock_slowpath+0x4b8/0x1490
   LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90
   --- interrupt: 500
    0xc0000029c1a41d00 (unreliable)
    _raw_spin_lock+0x6c/0x90
    futex_wake+0x100/0x260
    do_futex+0x21c/0x2a0
    sys_futex+0x98/0x270
    system_call_exception+0x14c/0x2f0
    system_call_vectored_common+0x15c/0x2ec

The following code flow illustrates how the deadlock occurs.
For the sake of brevity, assume that both locks (A and B) are
contended and we call the queued_spin_lock_slowpath() function.

        CPU0                                   CPU1
        ----                                   ----
  spin_lock_irqsave(A)                          |
  spin_unlock_irqrestore(A)                     |
    spin_lock(B)                                |
         |                                      |
         ▼                                      |
   id = qnodesp-&gt;count++;                       |
  (Note that nodes[0].lock == A)                |
         |                                      |
         ▼                                      |
      Interrupt                                 |
  (happens before "nodes[0].lock = B")          |
         |                                      |
         ▼                                      |
  spin_lock_irqsave(A)                          |
         |                                      |
         ▼                                      |
   id = qnodesp-&gt;count++                        |
   nodes[1].lock = A                            |
         |                                      |
         ▼                                      |
  Tail of MCS queue                             |
         |                             spin_lock_irqsave(A)
         ▼                                      |
  Head of MCS queue                             ▼
         |                             CPU0 is previous tail
         ▼                                      |
   Spin indefinitely                            ▼
  (until "nodes[1].next != NULL")      prev = get_tail_qnode(A, CPU0)
                                                |
                                                ▼
                                       prev == &amp;qnodes[CPU0].nodes[0]
                                     (as qnodes[CPU0].nodes[0].lock == A)
                                                |
                                                ▼
                                       WRITE_ONCE(prev-&gt;next, node)
                                                |
                                                ▼
                                        Spin indefinitely
                                     (until nodes[0].locked == 1)

Thanks to Saket Kumar Bhaskar for help with recreating the issue

Fixes: 84990b169557 ("powerpc/qspinlock: add mcs queueing for contended waiters")
Cc: stable@vger.kernel.org # v6.2+
Reported-by: Geetika Moolchandani &lt;geetika@linux.ibm.com&gt;
Reported-by: Vaishnavi Bhat &lt;vaish123@in.ibm.com&gt;
Reported-by: Jijo Varghese &lt;vargjijo@in.ibm.com&gt;
Signed-off-by: Nysal Jan K.A. &lt;nysal@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240829022830.1164355-1-nysal@linux.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If an interrupt occurs in queued_spin_lock_slowpath() after we increment
qnodesp-&gt;count and before node-&gt;lock is initialized, another CPU might
see stale lock values in get_tail_qnode(). If the stale lock value happens
to match the lock on that CPU, then we write to the "next" pointer of
the wrong qnode. This causes a deadlock as the former CPU, once it becomes
the head of the MCS queue, will spin indefinitely until it's "next" pointer
is set by its successor in the queue.

Running stress-ng on a 16 core (16EC/16VP) shared LPAR, results in
occasional lockups similar to the following:

   $ stress-ng --all 128 --vm-bytes 80% --aggressive \
               --maximize --oomable --verify  --syslog \
               --metrics  --times  --timeout 5m

   watchdog: CPU 15 Hard LOCKUP
   ......
   NIP [c0000000000b78f4] queued_spin_lock_slowpath+0x1184/0x1490
   LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90
   Call Trace:
    0xc000002cfffa3bf0 (unreliable)
    _raw_spin_lock+0x6c/0x90
    raw_spin_rq_lock_nested.part.135+0x4c/0xd0
    sched_ttwu_pending+0x60/0x1f0
    __flush_smp_call_function_queue+0x1dc/0x670
    smp_ipi_demux_relaxed+0xa4/0x100
    xive_muxed_ipi_action+0x20/0x40
    __handle_irq_event_percpu+0x80/0x240
    handle_irq_event_percpu+0x2c/0x80
    handle_percpu_irq+0x84/0xd0
    generic_handle_irq+0x54/0x80
    __do_irq+0xac/0x210
    __do_IRQ+0x74/0xd0
    0x0
    do_IRQ+0x8c/0x170
    hardware_interrupt_common_virt+0x29c/0x2a0
   --- interrupt: 500 at queued_spin_lock_slowpath+0x4b8/0x1490
   ......
   NIP [c0000000000b6c28] queued_spin_lock_slowpath+0x4b8/0x1490
   LR [c000000001037c5c] _raw_spin_lock+0x6c/0x90
   --- interrupt: 500
    0xc0000029c1a41d00 (unreliable)
    _raw_spin_lock+0x6c/0x90
    futex_wake+0x100/0x260
    do_futex+0x21c/0x2a0
    sys_futex+0x98/0x270
    system_call_exception+0x14c/0x2f0
    system_call_vectored_common+0x15c/0x2ec

The following code flow illustrates how the deadlock occurs.
For the sake of brevity, assume that both locks (A and B) are
contended and we call the queued_spin_lock_slowpath() function.

        CPU0                                   CPU1
        ----                                   ----
  spin_lock_irqsave(A)                          |
  spin_unlock_irqrestore(A)                     |
    spin_lock(B)                                |
         |                                      |
         ▼                                      |
   id = qnodesp-&gt;count++;                       |
  (Note that nodes[0].lock == A)                |
         |                                      |
         ▼                                      |
      Interrupt                                 |
  (happens before "nodes[0].lock = B")          |
         |                                      |
         ▼                                      |
  spin_lock_irqsave(A)                          |
         |                                      |
         ▼                                      |
   id = qnodesp-&gt;count++                        |
   nodes[1].lock = A                            |
         |                                      |
         ▼                                      |
  Tail of MCS queue                             |
         |                             spin_lock_irqsave(A)
         ▼                                      |
  Head of MCS queue                             ▼
         |                             CPU0 is previous tail
         ▼                                      |
   Spin indefinitely                            ▼
  (until "nodes[1].next != NULL")      prev = get_tail_qnode(A, CPU0)
                                                |
                                                ▼
                                       prev == &amp;qnodes[CPU0].nodes[0]
                                     (as qnodes[CPU0].nodes[0].lock == A)
                                                |
                                                ▼
                                       WRITE_ONCE(prev-&gt;next, node)
                                                |
                                                ▼
                                        Spin indefinitely
                                     (until nodes[0].locked == 1)

Thanks to Saket Kumar Bhaskar for help with recreating the issue

Fixes: 84990b169557 ("powerpc/qspinlock: add mcs queueing for contended waiters")
Cc: stable@vger.kernel.org # v6.2+
Reported-by: Geetika Moolchandani &lt;geetika@linux.ibm.com&gt;
Reported-by: Vaishnavi Bhat &lt;vaish123@in.ibm.com&gt;
Reported-by: Jijo Varghese &lt;vargjijo@in.ibm.com&gt;
Signed-off-by: Nysal Jan K.A. &lt;nysal@linux.ibm.com&gt;
Reviewed-by: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240829022830.1164355-1-nysal@linux.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/code-patching: Add boot selftest for data patching</title>
<updated>2024-08-21T10:15:13+00:00</updated>
<author>
<name>Benjamin Gray</name>
<email>bgray@linux.ibm.com</email>
</author>
<published>2024-05-15T02:44:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b7d47339d00d89af559a7068f4a640fc828177ad'/>
<id>b7d47339d00d89af559a7068f4a640fc828177ad</id>
<content type='text'>
Extend the code patching selftests with some basic coverage of the new
data patching variants too.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-6-bgray@linux.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Extend the code patching selftests with some basic coverage of the new
data patching variants too.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-6-bgray@linux.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/code-patching: Add data patch alignment check</title>
<updated>2024-08-21T10:15:12+00:00</updated>
<author>
<name>Benjamin Gray</name>
<email>bgray@linux.ibm.com</email>
</author>
<published>2024-05-15T02:44:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dbf828aab466c6534711d1f1454c409ea68d18d0'/>
<id>dbf828aab466c6534711d1f1454c409ea68d18d0</id>
<content type='text'>
The new data patching still needs to be aligned within a
cacheline too for the flushes to work correctly. To simplify
this requirement, we just say data patches must be aligned.

Detect when data patching is not aligned, returning an invalid
argument error.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Acked-by: Naveen N Rao &lt;naveen@kernel.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-3-bgray@linux.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The new data patching still needs to be aligned within a
cacheline too for the flushes to work correctly. To simplify
this requirement, we just say data patches must be aligned.

Detect when data patching is not aligned, returning an invalid
argument error.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Acked-by: Naveen N Rao &lt;naveen@kernel.org&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-3-bgray@linux.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/code-patching: Add generic memory patching</title>
<updated>2024-08-21T10:15:12+00:00</updated>
<author>
<name>Benjamin Gray</name>
<email>bgray@linux.ibm.com</email>
</author>
<published>2024-05-15T02:44:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e6b8940e7e80cdfe98ba8493214922998920dd9c'/>
<id>e6b8940e7e80cdfe98ba8493214922998920dd9c</id>
<content type='text'>
patch_instruction() is designed for patching instructions in otherwise
readonly memory. Other consumers also sometimes need to patch readonly
memory, so have abused patch_instruction() for arbitrary data patches.

This is a problem on ppc64 as patch_instruction() decides on the patch
width using the 'instruction' opcode to see if it's a prefixed
instruction. Data that triggers this can lead to larger writes, possibly
crossing a page boundary and failing the write altogether.

Introduce patch_uint(), and patch_ulong(), with aliases patch_u32(), and
patch_u64() (on ppc64) designed for aligned data patches. The patch
size is now determined by the called function, and is passed as an
additional parameter to generic internals.

While the instruction flushing is not required for data patches, it
remains unconditional in this patch. A followup series is possible if
benchmarking shows fewer flushes gives an improvement in some
data-patching workload.

ppc32 does not support prefixed instructions, so is unaffected by the
original issue. Care is taken in not exposing the size parameter in the
public (non-static) interface, so the compiler can const-propagate it
away.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-2-bgray@linux.ibm.com

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
patch_instruction() is designed for patching instructions in otherwise
readonly memory. Other consumers also sometimes need to patch readonly
memory, so have abused patch_instruction() for arbitrary data patches.

This is a problem on ppc64 as patch_instruction() decides on the patch
width using the 'instruction' opcode to see if it's a prefixed
instruction. Data that triggers this can lead to larger writes, possibly
crossing a page boundary and failing the write altogether.

Introduce patch_uint(), and patch_ulong(), with aliases patch_u32(), and
patch_u64() (on ppc64) designed for aligned data patches. The patch
size is now determined by the called function, and is passed as an
additional parameter to generic internals.

While the instruction flushing is not required for data patches, it
remains unconditional in this patch. A followup series is possible if
benchmarking shows fewer flushes gives an improvement in some
data-patching workload.

ppc32 does not support prefixed instructions, so is unaffected by the
original issue. Care is taken in not exposing the size parameter in the
public (non-static) interface, so the compiler can const-propagate it
away.

Signed-off-by: Benjamin Gray &lt;bgray@linux.ibm.com&gt;
Reviewed-by: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://msgid.link/20240515024445.236364-2-bgray@linux.ibm.com

</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2024-05-17T16:05:46+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-17T16:05:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ff2632d7d08edc11e8bd0629e9fcfebab25c78b4'/>
<id>ff2632d7d08edc11e8bd0629e9fcfebab25c78b4</id>
<content type='text'>
Pull powerpc updates from Michael Ellerman:

 - Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.

 - Allow per-process DEXCR (Dynamic Execution Control Register) settings
   via prctl, notably NPHIE which controls hashst/hashchk for ROP
   protection.

 - Install powerpc selftests in sub-directories. Note this changes the
   way run_kselftest.sh needs to be invoked for powerpc selftests.

 - Change fadump (Firmware Assisted Dump) to better handle memory
   add/remove.

 - Add support for passing additional parameters to the fadump kernel.

 - Add support for updating the kdump image on CPU/memory add/remove
   events.

 - Other small features, cleanups and fixes.

Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd
Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe
Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David
Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff
Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin
Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan
Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang,
Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth
Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui.

* tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits)
  powerpc/fadump: Fix section mismatch warning
  powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP
  powerpc/fadump: update documentation about bootargs_append
  powerpc/fadump: pass additional parameters when fadump is active
  powerpc/fadump: setup additional parameters for dump capture kernel
  powerpc/pseries/fadump: add support for multiple boot memory regions
  selftests/powerpc/dexcr: Fix spelling mistake "predicition" -&gt; "prediction"
  KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
  KVM: PPC: Fix documentation for ppc mmu caps
  KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
  KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
  powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
  powerpc/code-patching: Use dedicated memory routines for patching
  powerpc/code-patching: Test patch_instructions() during boot
  powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region()
  powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
  powerpc: Fix typos
  powerpc/eeh: Fix spelling of the word "auxillary" and update comment
  macintosh/ams: Fix unused variable warning
  powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc updates from Michael Ellerman:

 - Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.

 - Allow per-process DEXCR (Dynamic Execution Control Register) settings
   via prctl, notably NPHIE which controls hashst/hashchk for ROP
   protection.

 - Install powerpc selftests in sub-directories. Note this changes the
   way run_kselftest.sh needs to be invoked for powerpc selftests.

 - Change fadump (Firmware Assisted Dump) to better handle memory
   add/remove.

 - Add support for passing additional parameters to the fadump kernel.

 - Add support for updating the kdump image on CPU/memory add/remove
   events.

 - Other small features, cleanups and fixes.

Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd
Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe
Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David
Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff
Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin
Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan
Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang,
Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth
Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui.

* tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits)
  powerpc/fadump: Fix section mismatch warning
  powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP
  powerpc/fadump: update documentation about bootargs_append
  powerpc/fadump: pass additional parameters when fadump is active
  powerpc/fadump: setup additional parameters for dump capture kernel
  powerpc/pseries/fadump: add support for multiple boot memory regions
  selftests/powerpc/dexcr: Fix spelling mistake "predicition" -&gt; "prediction"
  KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
  KVM: PPC: Fix documentation for ppc mmu caps
  KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
  KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
  powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
  powerpc/code-patching: Use dedicated memory routines for patching
  powerpc/code-patching: Test patch_instructions() during boot
  powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region()
  powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
  powerpc: Fix typos
  powerpc/eeh: Fix spelling of the word "auxillary" and update comment
  macintosh/ams: Fix unused variable warning
  powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large
  ...
</pre>
</div>
</content>
</entry>
</feed>
