<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/arc/include, branch v5.13.2</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ARCv2: save ABI registers across signal handling</title>
<updated>2021-06-11T00:21:38+00:00</updated>
<author>
<name>Vineet Gupta</name>
<email>vgupta@synopsys.com</email>
</author>
<published>2021-06-09T02:39:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=96f1b00138cb8f04c742c82d0a7c460b2202e887'/>
<id>96f1b00138cb8f04c742c82d0a7c460b2202e887</id>
<content type='text'>
ARCv2 has some configuration dependent registers (r30, r58, r59) which
could be targetted by the compiler. To keep the ABI stable, these were
unconditionally part of the glibc ABI
(sysdeps/unix/sysv/linux/arc/sys/ucontext.h:mcontext_t) however we
missed populating them (by saving/restoring them across signal
handling).

This patch fixes the issue by
 - adding arcv2 ABI regs to kernel struct sigcontext
 - populating them during signal handling

Change to struct sigcontext might seem like a glibc ABI change (although
it primarily uses ucontext_t:mcontext_t) but the fact is
 - it has only been extended (existing fields are not touched)
 - the old sigcontext was ABI incomplete to begin with anyways

Fixes: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/53
Cc: &lt;stable@vger.kernel.org&gt;
Tested-by: kernel test robot &lt;lkp@intel.com&gt;
Reported-by: Vladimir Isaev &lt;isaev@synopsys.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
ARCv2 has some configuration dependent registers (r30, r58, r59) which
could be targetted by the compiler. To keep the ABI stable, these were
unconditionally part of the glibc ABI
(sysdeps/unix/sysv/linux/arc/sys/ucontext.h:mcontext_t) however we
missed populating them (by saving/restoring them across signal
handling).

This patch fixes the issue by
 - adding arcv2 ABI regs to kernel struct sigcontext
 - populating them during signal handling

Change to struct sigcontext might seem like a glibc ABI change (although
it primarily uses ucontext_t:mcontext_t) but the fact is
 - it has only been extended (existing fields are not touched)
 - the old sigcontext was ABI incomplete to begin with anyways

Fixes: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/53
Cc: &lt;stable@vger.kernel.org&gt;
Tested-by: kernel test robot &lt;lkp@intel.com&gt;
Reported-by: Vladimir Isaev &lt;isaev@synopsys.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: mm: PAE: use 40-bit physical page mask</title>
<updated>2021-05-10T19:38:59+00:00</updated>
<author>
<name>Vladimir Isaev</name>
<email>isaev@synopsys.com</email>
</author>
<published>2021-04-27T12:12:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c5f756d8c6265ebb1736a7787231f010a3b782e5'/>
<id>c5f756d8c6265ebb1736a7787231f010a3b782e5</id>
<content type='text'>
32-bit PAGE_MASK can not be used as a mask for physical addresses
when PAE is enabled. PAGE_MASK_PHYS must be used for physical
addresses instead of PAGE_MASK.

Without this, init gets SIGSEGV if pte_modify was called:

| potentially unexpected fatal signal 11.
| Path: /bin/busybox
| CPU: 0 PID: 1 Comm: init Not tainted 5.12.0-rc5-00003-g1e43c377a79f-dirty
| Insn could not be fetched
|     @No matching VMA found
|  ECR: 0x00040000 EFA: 0x00000000 ERET: 0x00000000
| STAT: 0x80080082 [IE U     ]   BTA: 0x00000000
|  SP: 0x5f9ffe44  FP: 0x00000000 BLK: 0xaf3d4
| LPS: 0x000d093e LPE: 0x000d0950 LPC: 0x00000000
| r00: 0x00000002 r01: 0x5f9fff14 r02: 0x5f9fff20
| ...
| Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

Signed-off-by: Vladimir Isaev &lt;isaev@synopsys.com&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
32-bit PAGE_MASK can not be used as a mask for physical addresses
when PAE is enabled. PAGE_MASK_PHYS must be used for physical
addresses instead of PAGE_MASK.

Without this, init gets SIGSEGV if pte_modify was called:

| potentially unexpected fatal signal 11.
| Path: /bin/busybox
| CPU: 0 PID: 1 Comm: init Not tainted 5.12.0-rc5-00003-g1e43c377a79f-dirty
| Insn could not be fetched
|     @No matching VMA found
|  ECR: 0x00040000 EFA: 0x00000000 ERET: 0x00000000
| STAT: 0x80080082 [IE U     ]   BTA: 0x00000000
|  SP: 0x5f9ffe44  FP: 0x00000000 BLK: 0xaf3d4
| LPS: 0x000d093e LPE: 0x000d0950 LPC: 0x00000000
| r00: 0x00000002 r01: 0x5f9fff14 r02: 0x5f9fff20
| ...
| Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

Signed-off-by: Vladimir Isaev &lt;isaev@synopsys.com&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arc: Fix typos/spellos</title>
<updated>2021-05-10T19:38:59+00:00</updated>
<author>
<name>Bhaskar Chowdhury</name>
<email>unixbhaskar@gmail.com</email>
</author>
<published>2021-03-22T12:28:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f79f7a2d96769d2a3e663a3e673066be77c30cc3'/>
<id>f79f7a2d96769d2a3e663a3e673066be77c30cc3</id>
<content type='text'>
s/commiting/committing/
s/defintion/definition/
s/gaurantees/guarantees/
s/interrpted/interrupted/
s/interrutps/interrupts/
s/succeded/succeeded/
s/unconditonally/unconditionally/

Reviewed-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
s/commiting/committing/
s/defintion/definition/
s/gaurantees/guarantees/
s/interrpted/interrupted/
s/interrutps/interrupts/
s/succeded/succeeded/
s/unconditonally/unconditionally/

Reviewed-by: Christian Brauner &lt;christian.brauner@ubuntu.com&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Bhaskar Chowdhury &lt;unixbhaskar@gmail.com&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arch/arc: add copy_user_page() to &lt;asm/page.h&gt; to fix build error on ARC</title>
<updated>2021-01-05T20:59:40+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2021-01-05T03:44:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8a48c0a3360bf2bf4f40c980d0ec216e770e58ee'/>
<id>8a48c0a3360bf2bf4f40c980d0ec216e770e58ee</id>
<content type='text'>
fs/dax.c uses copy_user_page() but ARC does not provide that interface,
resulting in a build error.

Provide copy_user_page() in &lt;asm/page.h&gt;.

../fs/dax.c: In function 'copy_cow_page_dax':
../fs/dax.c:702:2: error: implicit declaration of function 'copy_user_page'; did you mean 'copy_to_user_page'? [-Werror=implicit-function-declaration]

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: linux-snps-arc@lists.infradead.org
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
#Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt; # v1
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
#Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt; # v2
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
fs/dax.c uses copy_user_page() but ARC does not provide that interface,
resulting in a build error.

Provide copy_user_page() in &lt;asm/page.h&gt;.

../fs/dax.c: In function 'copy_cow_page_dax':
../fs/dax.c:702:2: error: implicit declaration of function 'copy_user_page'; did you mean 'copy_to_user_page'? [-Werror=implicit-function-declaration]

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: linux-snps-arc@lists.infradead.org
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
#Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt; # v1
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
#Reviewed-by: Ira Weiny &lt;ira.weiny@intel.com&gt; # v2
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>local64.h: make &lt;asm/local64.h&gt; mandatory</title>
<updated>2020-12-29T23:36:49+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2020-12-29T23:14:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=87dbc209ea04645fd2351981f09eff5d23f8e2e9'/>
<id>87dbc209ea04645fd2351981f09eff5d23f8e2e9</id>
<content type='text'>
Make &lt;asm-generic/local64.h&gt; mandatory in include/asm-generic/Kbuild and
remove all arch/*/include/asm/local64.h arch-specific files since they
only #include &lt;asm-generic/local64.h&gt;.

This fixes build errors on arch/c6x/ and arch/nios2/ for
block/blk-iocost.c.

Build-tested on 21 of 25 arch-es.  (tools problems on the others)

Yes, we could even rename &lt;asm-generic/local64.h&gt; to
&lt;linux/local64.h&gt; and change all #includes to use
&lt;linux/local64.h&gt; instead.

Link: https://lkml.kernel.org/r/20201227024446.17018-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Reviewed-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Aurelien Jacquiot &lt;jacquiot.aurelien@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Make &lt;asm-generic/local64.h&gt; mandatory in include/asm-generic/Kbuild and
remove all arch/*/include/asm/local64.h arch-specific files since they
only #include &lt;asm-generic/local64.h&gt;.

This fixes build errors on arch/c6x/ and arch/nios2/ for
block/blk-iocost.c.

Build-tested on 21 of 25 arch-es.  (tools problems on the others)

Yes, we could even rename &lt;asm-generic/local64.h&gt; to
&lt;linux/local64.h&gt; and change all #includes to use
&lt;linux/local64.h&gt; instead.

Link: https://lkml.kernel.org/r/20201227024446.17018-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Reviewed-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Ley Foon Tan &lt;ley.foon.tan@intel.com&gt;
Cc: Mark Salter &lt;msalter@redhat.com&gt;
Cc: Aurelien Jacquiot &lt;jacquiot.aurelien@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block</title>
<updated>2020-12-16T20:33:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-16T20:33:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=005b2a9dc819a1265a8c765595f8f6d88d6173d9'/>
<id>005b2a9dc819a1265a8c765595f8f6d88d6173d9</id>
<content type='text'>
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe:
 "This sits on top of of the core entry/exit and x86 entry branch from
  the tip tree, which contains the generic and x86 parts of this work.

  Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL.

  With that done, we can get rid of JOBCTL_TASK_WORK from task_work and
  signal.c, and also remove a deadlock work-around in io_uring around
  knowing that signal based task_work waking is invoked with the sighand
  wait queue head lock.

  The motivation for this work is to decouple signal notify based
  task_work, of which io_uring is a heavy user of, from sighand. The
  sighand lock becomes a huge contention point, particularly for
  threaded workloads where it's shared between threads. Even outside of
  threaded applications it's slower than it needs to be.

  Roman Gershman &lt;romger@amazon.com&gt; reported that his networked
  workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU
  after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all
  spent hammering on the sighand lock, showing 57% of the CPU time there
  [1].

  There are further cleanups possible on top of this. One example is
  TIF_PATCH_PENDING, where a patch already exists to use
  TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more
  consolidation, but the work stands on its own as well"

[1] https://github.com/axboe/liburing/issues/215

* tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits)
  io_uring: remove 'twa_signal_ok' deadlock work-around
  kernel: remove checking for TIF_NOTIFY_SIGNAL
  signal: kill JOBCTL_TASK_WORK
  io_uring: JOBCTL_TASK_WORK is no longer used by task_work
  task_work: remove legacy TWA_SIGNAL path
  sparc: add support for TIF_NOTIFY_SIGNAL
  riscv: add support for TIF_NOTIFY_SIGNAL
  nds32: add support for TIF_NOTIFY_SIGNAL
  ia64: add support for TIF_NOTIFY_SIGNAL
  h8300: add support for TIF_NOTIFY_SIGNAL
  c6x: add support for TIF_NOTIFY_SIGNAL
  alpha: add support for TIF_NOTIFY_SIGNAL
  xtensa: add support for TIF_NOTIFY_SIGNAL
  arm: add support for TIF_NOTIFY_SIGNAL
  microblaze: add support for TIF_NOTIFY_SIGNAL
  hexagon: add support for TIF_NOTIFY_SIGNAL
  csky: add support for TIF_NOTIFY_SIGNAL
  openrisc: add support for TIF_NOTIFY_SIGNAL
  sh: add support for TIF_NOTIFY_SIGNAL
  um: add support for TIF_NOTIFY_SIGNAL
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe:
 "This sits on top of of the core entry/exit and x86 entry branch from
  the tip tree, which contains the generic and x86 parts of this work.

  Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL.

  With that done, we can get rid of JOBCTL_TASK_WORK from task_work and
  signal.c, and also remove a deadlock work-around in io_uring around
  knowing that signal based task_work waking is invoked with the sighand
  wait queue head lock.

  The motivation for this work is to decouple signal notify based
  task_work, of which io_uring is a heavy user of, from sighand. The
  sighand lock becomes a huge contention point, particularly for
  threaded workloads where it's shared between threads. Even outside of
  threaded applications it's slower than it needs to be.

  Roman Gershman &lt;romger@amazon.com&gt; reported that his networked
  workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU
  after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all
  spent hammering on the sighand lock, showing 57% of the CPU time there
  [1].

  There are further cleanups possible on top of this. One example is
  TIF_PATCH_PENDING, where a patch already exists to use
  TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more
  consolidation, but the work stands on its own as well"

[1] https://github.com/axboe/liburing/issues/215

* tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits)
  io_uring: remove 'twa_signal_ok' deadlock work-around
  kernel: remove checking for TIF_NOTIFY_SIGNAL
  signal: kill JOBCTL_TASK_WORK
  io_uring: JOBCTL_TASK_WORK is no longer used by task_work
  task_work: remove legacy TWA_SIGNAL path
  sparc: add support for TIF_NOTIFY_SIGNAL
  riscv: add support for TIF_NOTIFY_SIGNAL
  nds32: add support for TIF_NOTIFY_SIGNAL
  ia64: add support for TIF_NOTIFY_SIGNAL
  h8300: add support for TIF_NOTIFY_SIGNAL
  c6x: add support for TIF_NOTIFY_SIGNAL
  alpha: add support for TIF_NOTIFY_SIGNAL
  xtensa: add support for TIF_NOTIFY_SIGNAL
  arm: add support for TIF_NOTIFY_SIGNAL
  microblaze: add support for TIF_NOTIFY_SIGNAL
  hexagon: add support for TIF_NOTIFY_SIGNAL
  csky: add support for TIF_NOTIFY_SIGNAL
  openrisc: add support for TIF_NOTIFY_SIGNAL
  sh: add support for TIF_NOTIFY_SIGNAL
  um: add support for TIF_NOTIFY_SIGNAL
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'asm-generic-mmu-context-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic</title>
<updated>2020-12-16T07:58:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-16T07:58:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=157807123c94acc8dcddd08a2335bd0173c5d68d'/>
<id>157807123c94acc8dcddd08a2335bd0173c5d68d</id>
<content type='text'>
Pull asm-generic mmu-context cleanup from Arnd Bergmann:
 "This is a cleanup series from Nicholas Piggin, preparing for later
  changes. The asm/mmu_context.h header are generalized and common code
  moved to asm-gneneric/mmu_context.h.

  This saves a bit of code and makes it easier to change in the future"

* tag 'asm-generic-mmu-context-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (25 commits)
  h8300: Fix generic mmu_context build
  m68k: mmu_context: Fix Sun-3 build
  xtensa: use asm-generic/mmu_context.h for no-op implementations
  x86: use asm-generic/mmu_context.h for no-op implementations
  um: use asm-generic/mmu_context.h for no-op implementations
  sparc: use asm-generic/mmu_context.h for no-op implementations
  sh: use asm-generic/mmu_context.h for no-op implementations
  s390: use asm-generic/mmu_context.h for no-op implementations
  riscv: use asm-generic/mmu_context.h for no-op implementations
  powerpc: use asm-generic/mmu_context.h for no-op implementations
  parisc: use asm-generic/mmu_context.h for no-op implementations
  openrisc: use asm-generic/mmu_context.h for no-op implementations
  nios2: use asm-generic/mmu_context.h for no-op implementations
  nds32: use asm-generic/mmu_context.h for no-op implementations
  mips: use asm-generic/mmu_context.h for no-op implementations
  microblaze: use asm-generic/mmu_context.h for no-op implementations
  m68k: use asm-generic/mmu_context.h for no-op implementations
  ia64: use asm-generic/mmu_context.h for no-op implementations
  hexagon: use asm-generic/mmu_context.h for no-op implementations
  csky: use asm-generic/mmu_context.h for no-op implementations
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull asm-generic mmu-context cleanup from Arnd Bergmann:
 "This is a cleanup series from Nicholas Piggin, preparing for later
  changes. The asm/mmu_context.h header are generalized and common code
  moved to asm-gneneric/mmu_context.h.

  This saves a bit of code and makes it easier to change in the future"

* tag 'asm-generic-mmu-context-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (25 commits)
  h8300: Fix generic mmu_context build
  m68k: mmu_context: Fix Sun-3 build
  xtensa: use asm-generic/mmu_context.h for no-op implementations
  x86: use asm-generic/mmu_context.h for no-op implementations
  um: use asm-generic/mmu_context.h for no-op implementations
  sparc: use asm-generic/mmu_context.h for no-op implementations
  sh: use asm-generic/mmu_context.h for no-op implementations
  s390: use asm-generic/mmu_context.h for no-op implementations
  riscv: use asm-generic/mmu_context.h for no-op implementations
  powerpc: use asm-generic/mmu_context.h for no-op implementations
  parisc: use asm-generic/mmu_context.h for no-op implementations
  openrisc: use asm-generic/mmu_context.h for no-op implementations
  nios2: use asm-generic/mmu_context.h for no-op implementations
  nds32: use asm-generic/mmu_context.h for no-op implementations
  mips: use asm-generic/mmu_context.h for no-op implementations
  microblaze: use asm-generic/mmu_context.h for no-op implementations
  m68k: use asm-generic/mmu_context.h for no-op implementations
  ia64: use asm-generic/mmu_context.h for no-op implementations
  hexagon: use asm-generic/mmu_context.h for no-op implementations
  csky: use asm-generic/mmu_context.h for no-op implementations
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2020-12-15T20:53:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-15T20:53:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ac73e3dc8acd0a3be292755db30388c3580f5674'/>
<id>ac73e3dc8acd0a3be292755db30388c3580f5674</id>
<content type='text'>
Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>arc: use FLATMEM with freeing of unused memory map instead of DISCONTIGMEM</title>
<updated>2020-12-15T20:13:42+00:00</updated>
<author>
<name>Mike Rapoport</name>
<email>rppt@linux.ibm.com</email>
</author>
<published>2020-12-15T03:10:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=050b2da268f8fc4f8123f6462c430a61547b2f7b'/>
<id>050b2da268f8fc4f8123f6462c430a61547b2f7b</id>
<content type='text'>
Currently ARC uses DISCONTIGMEM to cope with sparse physical memory address
space on systems with 2 memory banks. While DISCONTIGMEM avoids wasting
memory on unpopulated memory map, it adds both memory and CPU overhead
relatively to FLATMEM. Moreover, DISCONTINGMEM is generally considered
deprecated.

The obvious replacement for DISCONTIGMEM would be SPARSEMEM, but it is also
less efficient than FLATMEM in pfn_to_page() and page_to_pfn() conversions.
Besides it requires tuning of SECTION_SIZE which is not trivial for
possible ARC memory configuration.

Since the memory map for both banks is always allocated from the "lowmem"
bank, it is possible to use FLATMEM for two-bank configuration and simply
free the unused hole in the memory map. All is required for that is to
provide ARC-specific pfn_valid() that will take into account actual
physical memory configuration and define HAVE_ARCH_PFN_VALID.

The resulting kernel image configured with defconfig + HIGHMEM=y is
smaller:

  $ size a/vmlinux b/vmlinux
     text    data     bss     dec     hex filename
  4673503 1245456  279756 6198715  5e95bb a/vmlinux
  4658706 1246864  279756 6185326  5e616e b/vmlinux

  $ ./scripts/bloat-o-meter a/vmlinux b/vmlinux
  add/remove: 28/30 grow/shrink: 42/399 up/down: 10986/-29025 (-18039)
  ...
  Total: Before=4709315, After = 4691276, chg -0.38%

Booting nSIM with haps_ns.dts results in the following memory usage
reports:

  a:
  Memory: 1559104K/1572864K available (3531K kernel code, 595K rwdata, 752K rodata, 136K init, 275K bss, 13760K reserved, 0K cma-reserved, 1048576K highmem)

  b:
  Memory: 1559112K/1572864K available (3519K kernel code, 594K rwdata, 752K rodata, 136K init, 280K bss, 13752K reserved, 0K cma-reserved, 1048576K highmem)

Link: https://lkml.kernel.org/r/20201101170454.9567-11-rppt@kernel.org
Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Meelis Roos &lt;mroos@linux.ee&gt;
Cc: Michael Schmitz &lt;schmitzmic@gmail.com&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently ARC uses DISCONTIGMEM to cope with sparse physical memory address
space on systems with 2 memory banks. While DISCONTIGMEM avoids wasting
memory on unpopulated memory map, it adds both memory and CPU overhead
relatively to FLATMEM. Moreover, DISCONTINGMEM is generally considered
deprecated.

The obvious replacement for DISCONTIGMEM would be SPARSEMEM, but it is also
less efficient than FLATMEM in pfn_to_page() and page_to_pfn() conversions.
Besides it requires tuning of SECTION_SIZE which is not trivial for
possible ARC memory configuration.

Since the memory map for both banks is always allocated from the "lowmem"
bank, it is possible to use FLATMEM for two-bank configuration and simply
free the unused hole in the memory map. All is required for that is to
provide ARC-specific pfn_valid() that will take into account actual
physical memory configuration and define HAVE_ARCH_PFN_VALID.

The resulting kernel image configured with defconfig + HIGHMEM=y is
smaller:

  $ size a/vmlinux b/vmlinux
     text    data     bss     dec     hex filename
  4673503 1245456  279756 6198715  5e95bb a/vmlinux
  4658706 1246864  279756 6185326  5e616e b/vmlinux

  $ ./scripts/bloat-o-meter a/vmlinux b/vmlinux
  add/remove: 28/30 grow/shrink: 42/399 up/down: 10986/-29025 (-18039)
  ...
  Total: Before=4709315, After = 4691276, chg -0.38%

Booting nSIM with haps_ns.dts results in the following memory usage
reports:

  a:
  Memory: 1559104K/1572864K available (3531K kernel code, 595K rwdata, 752K rodata, 136K init, 275K bss, 13760K reserved, 0K cma-reserved, 1048576K highmem)

  b:
  Memory: 1559112K/1572864K available (3519K kernel code, 594K rwdata, 752K rodata, 136K init, 280K bss, 13752K reserved, 0K cma-reserved, 1048576K highmem)

Link: https://lkml.kernel.org/r/20201101170454.9567-11-rppt@kernel.org
Signed-off-by: Mike Rapoport &lt;rppt@linux.ibm.com&gt;
Cc: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Matt Turner &lt;mattst88@gmail.com&gt;
Cc: Meelis Roos &lt;mroos@linux.ee&gt;
Cc: Michael Schmitz &lt;schmitzmic@gmail.com&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-12-15T02:35:53+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-12-15T02:35:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=edd7ab76847442e299af64a761febd180d71f98d'/>
<id>edd7ab76847442e299af64a761febd180d71f98d</id>
<content type='text'>
Pull kmap updates from Thomas Gleixner:
 "The new preemtible kmap_local() implementation:

   - Consolidate all kmap_atomic() internals into a generic
     implementation which builds the base for the kmap_local() API and
     make the kmap_atomic() interface wrappers which handle the
     disabling/enabling of preemption and pagefaults.

   - Switch the storage from per-CPU to per task and provide scheduler
     support for clearing mapping when scheduling out and restoring them
     when scheduling back in.

   - Merge the migrate_disable/enable() code, which is also part of the
     scheduler pull request. This was required to make the kmap_local()
     interface available which does not disable preemption when a
     mapping is established. It has to disable migration instead to
     guarantee that the virtual address of the mapped slot is the same
     across preemption.

   - Provide better debug facilities: guard pages and enforced
     utilization of the mapping mechanics on 64bit systems when the
     architecture allows it.

   - Provide the new kmap_local() API which can now be used to cleanup
     the kmap_atomic() usage sites all over the place. Most of the usage
     sites do not require the implicit disabling of preemption and
     pagefaults so the penalty on 64bit and 32bit non-highmem systems is
     removed and quite some of the code can be simplified. A wholesale
     conversion is not possible because some usage depends on the
     implicit side effects and some need to be cleaned up because they
     work around these side effects.

     The migrate disable side effect is only effective on highmem
     systems and when enforced debugging is enabled. On 64bit and 32bit
     non-highmem systems the overhead is completely avoided"

* tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  ARM: highmem: Fix cache_is_vivt() reference
  x86/crashdump/32: Simplify copy_oldmem_page()
  io-mapping: Provide iomap_local variant
  mm/highmem: Provide kmap_local*
  sched: highmem: Store local kmaps in task struct
  x86: Support kmap_local() forced debugging
  mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL
  microblaze/mm/highmem: Add dropped #ifdef back
  xtensa/mm/highmem: Make generic kmap_atomic() work correctly
  mm/highmem: Take kmap_high_get() properly into account
  highmem: High implementation details and document API
  Documentation/io-mapping: Remove outdated blurb
  io-mapping: Cleanup atomic iomap
  mm/highmem: Remove the old kmap_atomic cruft
  highmem: Get rid of kmap_types.h
  xtensa/mm/highmem: Switch to generic kmap atomic
  sparc/mm/highmem: Switch to generic kmap atomic
  powerpc/mm/highmem: Switch to generic kmap atomic
  nds32/mm/highmem: Switch to generic kmap atomic
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kmap updates from Thomas Gleixner:
 "The new preemtible kmap_local() implementation:

   - Consolidate all kmap_atomic() internals into a generic
     implementation which builds the base for the kmap_local() API and
     make the kmap_atomic() interface wrappers which handle the
     disabling/enabling of preemption and pagefaults.

   - Switch the storage from per-CPU to per task and provide scheduler
     support for clearing mapping when scheduling out and restoring them
     when scheduling back in.

   - Merge the migrate_disable/enable() code, which is also part of the
     scheduler pull request. This was required to make the kmap_local()
     interface available which does not disable preemption when a
     mapping is established. It has to disable migration instead to
     guarantee that the virtual address of the mapped slot is the same
     across preemption.

   - Provide better debug facilities: guard pages and enforced
     utilization of the mapping mechanics on 64bit systems when the
     architecture allows it.

   - Provide the new kmap_local() API which can now be used to cleanup
     the kmap_atomic() usage sites all over the place. Most of the usage
     sites do not require the implicit disabling of preemption and
     pagefaults so the penalty on 64bit and 32bit non-highmem systems is
     removed and quite some of the code can be simplified. A wholesale
     conversion is not possible because some usage depends on the
     implicit side effects and some need to be cleaned up because they
     work around these side effects.

     The migrate disable side effect is only effective on highmem
     systems and when enforced debugging is enabled. On 64bit and 32bit
     non-highmem systems the overhead is completely avoided"

* tag 'core-mm-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  ARM: highmem: Fix cache_is_vivt() reference
  x86/crashdump/32: Simplify copy_oldmem_page()
  io-mapping: Provide iomap_local variant
  mm/highmem: Provide kmap_local*
  sched: highmem: Store local kmaps in task struct
  x86: Support kmap_local() forced debugging
  mm/highmem: Provide CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL
  microblaze/mm/highmem: Add dropped #ifdef back
  xtensa/mm/highmem: Make generic kmap_atomic() work correctly
  mm/highmem: Take kmap_high_get() properly into account
  highmem: High implementation details and document API
  Documentation/io-mapping: Remove outdated blurb
  io-mapping: Cleanup atomic iomap
  mm/highmem: Remove the old kmap_atomic cruft
  highmem: Get rid of kmap_types.h
  xtensa/mm/highmem: Switch to generic kmap atomic
  sparc/mm/highmem: Switch to generic kmap atomic
  powerpc/mm/highmem: Switch to generic kmap atomic
  nds32/mm/highmem: Switch to generic kmap atomic
  ...
</pre>
</div>
</content>
</entry>
</feed>
