<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/lib/Kconfig, branch linus/master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/lib/Kconfig?h=linus%2Fmaster</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/lib/Kconfig?h=linus%2Fmaster'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-06-12T06:51:51Z</updated>
<entry>
<title>crypto: memneq - move into lib/</title>
<updated>2022-06-12T06:51:51Z</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-05-28T10:24:29Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=abfed87e2a12bd246047d78c01d81eb9529f1d06'/>
<id>urn:sha1:abfed87e2a12bd246047d78c01d81eb9529f1d06</id>
<content type='text'>
This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a linker error Zheng pointed out when
CRYPTO_MANAGER_DISABLE_TESTS!=y and CRYPTO=m:

  lib/crypto/curve25519-selftest.o: In function `curve25519_selftest':
  curve25519-selftest.c:(.init.text+0x60): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0xec): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x114): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x154): undefined reference to `__crypto_memneq'

Reported-by: Zheng Bin &lt;zhengbin13@huawei.com&gt;
Cc: Eric Biggers &lt;ebiggers@kernel.org&gt;
Cc: stable@vger.kernel.org
Fixes: aa127963f1ca ("crypto: lib/curve25519 - re-add selftests")
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Reviewed-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>lib: add generic polynomial calculation</title>
<updated>2022-05-22T18:32:30Z</updated>
<author>
<name>Michael Walle</name>
<email>michael@walle.cc</email>
</author>
<published>2022-04-01T21:40:29Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=cd705ea857fdd859a9df09e8adda4cb4c906e8a2'/>
<id>urn:sha1:cd705ea857fdd859a9df09e8adda4cb4c906e8a2</id>
<content type='text'>
Some temperature and voltage sensors use a polynomial to convert between
raw data points and actual temperature or voltage. The polynomial is
usually the result of a curve fitting of the diode characteristic.

The BT1 PVT hwmon driver already uses such a polynonmial calculation
which is rather generic. Move it to lib/ so other drivers can reuse it.

Signed-off-by: Michael Walle &lt;michael@walle.cc&gt;
Reviewed-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Link: https://lore.kernel.org/r/20220401214032.3738095-2-michael@walle.cc
Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
</content>
</entry>
<entry>
<title>crypto: add rocksoft 64b crc guard tag framework</title>
<updated>2022-03-07T19:48:35Z</updated>
<author>
<name>Keith Busch</name>
<email>kbusch@kernel.org</email>
</author>
<published>2022-03-03T20:13:10Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=f3813f4b287e480b1fcd62ca798d8556644b8278'/>
<id>urn:sha1:f3813f4b287e480b1fcd62ca798d8556644b8278</id>
<content type='text'>
Hardware specific features may be able to calculate a crc64, so provide
a framework for drivers to register their implementation. If nothing is
registered, fallback to the generic table lookup implementation. The
implementation is modeled after the crct10dif equivalent.

Signed-off-by: Keith Busch &lt;kbusch@kernel.org&gt;
Link: https://lore.kernel.org/r/20220303201312.3255347-7-kbusch@kernel.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm</title>
<updated>2022-03-03T00:11:56Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-03T00:11:56Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=7e3d76139b5da7f58bda13c485e8e208ffce5c9c'/>
<id>urn:sha1:7e3d76139b5da7f58bda13c485e8e208ffce5c9c</id>
<content type='text'>
Pull ARM fixes from Russell King:

 - Fix kgdb breakpoint for Thumb2

 - Fix dependency for BITREVERSE kconfig

 - Fix nommu early_params and __setup returns

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9182/1: mmu: fix returns from early_param() and __setup() functions
  ARM: 9178/1: fix unmet dependency on BITREVERSE for HAVE_ARCH_BITREVERSE
  ARM: Fix kgdb breakpoint for Thumb2
</content>
</entry>
<entry>
<title>ARM: 9178/1: fix unmet dependency on BITREVERSE for HAVE_ARCH_BITREVERSE</title>
<updated>2022-02-21T14:58:34Z</updated>
<author>
<name>Julian Braha</name>
<email>julianbraha@gmail.com</email>
</author>
<published>2022-01-17T04:09:40Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=11c57c3ba94da74c3446924260e34e0b1950b5d7'/>
<id>urn:sha1:11c57c3ba94da74c3446924260e34e0b1950b5d7</id>
<content type='text'>
Resending this to properly add it to the patch tracker - thanks for letting
me know, Arnd :)

When ARM is enabled, and BITREVERSE is disabled,
Kbuild gives the following warning:

WARNING: unmet direct dependencies detected for HAVE_ARCH_BITREVERSE
  Depends on [n]: BITREVERSE [=n]
  Selected by [y]:
  - ARM [=y] &amp;&amp; (CPU_32v7M [=n] || CPU_32v7 [=y]) &amp;&amp; !CPU_32v6 [=n]

This is because ARM selects HAVE_ARCH_BITREVERSE
without selecting BITREVERSE, despite
HAVE_ARCH_BITREVERSE depending on BITREVERSE.

This unmet dependency bug was found by Kismet,
a static analysis tool for Kconfig. Please advise if this
is not the appropriate solution.

Signed-off-by: Julian Braha &lt;julianbraha@gmail.com&gt;
Signed-off-by: Russell King (Oracle) &lt;rmk+kernel@armlinux.org.uk&gt;
</content>
</entry>
<entry>
<title>Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linux</title>
<updated>2022-01-23T04:20:44Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-01-23T04:20:44Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=3689f9f8b0c52dfd8f5995e4b58917f8f3ac3ee3'/>
<id>urn:sha1:3689f9f8b0c52dfd8f5995e4b58917f8f3ac3ee3</id>
<content type='text'>
Pull bitmap updates from Yury Norov:

 - introduce for_each_set_bitrange()

 - use find_first_*_bit() instead of find_next_*_bit() where possible

 - unify for_each_bit() macros

* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
  vsprintf: rework bitmap_list_string
  lib: bitmap: add performance test for bitmap_print_to_pagebuf
  bitmap: unify find_bit operations
  mm/percpu: micro-optimize pcpu_is_populated()
  Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
  find: micro-optimize for_each_{set,clear}_bit()
  include/linux: move for_each_bit() macros from bitops.h to find.h
  cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
  tools: sync tools/bitmap with mother linux
  all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
  cpumask: use find_first_and_bit()
  lib: add find_first_and_bit()
  arch: remove GENERIC_FIND_FIRST_BIT entirely
  include: move find.h from asm_generic to linux
  bitops: move find_bit_*_le functions from le.h to find.h
  bitops: protect find_first_{,zero}_bit properly
</content>
</entry>
<entry>
<title>lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()</title>
<updated>2022-01-22T06:33:37Z</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@suse.cz</email>
</author>
<published>2022-01-22T06:14:27Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=2dba5eb1c73b6ba2988ced07250edeac0f8cbf5a'/>
<id>urn:sha1:2dba5eb1c73b6ba2988ced07250edeac0f8cbf5a</id>
<content type='text'>
Currently, enabling CONFIG_STACKDEPOT means its stack_table will be
allocated from memblock, even if stack depot ends up not actually used.
The default size of stack_table is 4MB on 32-bit, 8MB on 64-bit.

This is fine for use-cases such as KASAN which is also a config option
and has overhead on its own.  But it's an issue for functionality that
has to be actually enabled on boot (page_owner) or depends on hardware
(GPU drivers) and thus the memory might be wasted.  This was raised as
an issue [1] when attempting to add stackdepot support for SLUB's debug
object tracking functionality.  It's common to build kernels with
CONFIG_SLUB_DEBUG and enable slub_debug on boot only when needed, or
create only specific kmem caches with debugging for testing purposes.

It would thus be more efficient if stackdepot's table was allocated only
when actually going to be used.  This patch thus makes the allocation
(and whole stack_depot_init() call) optional:

 - Add a CONFIG_STACKDEPOT_ALWAYS_INIT flag to keep using the current
   well-defined point of allocation as part of mem_init(). Make
   CONFIG_KASAN select this flag.

 - Other users have to call stack_depot_init() as part of their own init
   when it's determined that stack depot will actually be used. This may
   depend on both config and runtime conditions. Convert current users
   which are page_owner and several in the DRM subsystem. Same will be
   done for SLUB later.

 - Because the init might now be called after the boot-time memblock
   allocation has given all memory to the buddy allocator, change
   stack_depot_init() to allocate stack_table with kvmalloc() when
   memblock is no longer available. Also handle allocation failure by
   disabling stackdepot (could have theoretically happened even with
   memblock allocation previously), and don't unnecessarily align the
   memblock allocation to its own size anymore.

[1] https://lore.kernel.org/all/CAMuHMdW=eoVzM1Re5FVoEN87nKfiLmM2+Ah7eNu2KXEhCvbZyA@mail.gmail.com/

Link: https://lkml.kernel.org/r/20211013073005.11351-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Acked-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Reviewed-by: Marco Elver &lt;elver@google.com&gt; # stackdepot
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Vijayanand Jitta &lt;vjitta@codeaurora.org&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Oliver Glitta &lt;glittao@gmail.com&gt;
Cc: Imran Khan &lt;imran.f.khan@oracle.com&gt;
From: Colin Ian King &lt;colin.king@canonical.com&gt;
Subject: lib/stackdepot: fix spelling mistake and grammar in pr_err message

There is a spelling mistake of the work allocation so fix this and
re-phrase the message to make it easier to read.

Link: https://lkml.kernel.org/r/20211015104159.11282-1-colin.king@canonical.com
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
From: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup

On FLATMEM, we call page_ext_init_flatmem_late() just before
kmem_cache_init() which means stack_depot_init() (called by page owner
init) will not recognize properly it should use kvmalloc() and not
memblock_alloc().  memblock_alloc() will also not issue a warning and
return a block memory that can be invalid and cause kernel page fault when
saving stacks, as reported by the kernel test robot [1].

Fix this by moving page_ext_init_flatmem_late() below kmem_cache_init() so
that slab_is_available() is true during stack_depot_init().  SPARSEMEM
doesn't have this issue, as it doesn't do page_ext_init_flatmem_late(),
but a different page_ext_init() even later in the boot process.

Thanks to Mike Rapoport for pointing out the FLATMEM init ordering issue.

While at it, also actually resolve a checkpatch warning in stack_depot_init()
from DRM CI, which was supposed to be in the original patch already.

[1] https://lore.kernel.org/all/20211014085450.GC18719@xsang-OptiPlex-9020/

Link: https://lkml.kernel.org/r/6abd9213-19a9-6d58-cedc-2414386d2d81@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Cc: Mike Rapoport &lt;rppt@kernel.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
From: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup3

Due to cd06ab2fd48f ("drm/locking: add backtrace for locking contended
locks without backoff") landing recently to -next adding a new stack depot
user in drivers/gpu/drm/drm_modeset_lock.c we need to add an appropriate
call to stack_depot_init() there as well.

Link: https://lkml.kernel.org/r/2a692365-cfa1-64f2-34e0-8aa5674dce5e@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Jani Nikula &lt;jani.nikula@intel.com&gt;
Cc: Naresh Kamboju &lt;naresh.kamboju@linaro.org&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Vijayanand Jitta &lt;vjitta@codeaurora.org&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Oliver Glitta &lt;glittao@gmail.com&gt;
Cc: Imran Khan &lt;imran.f.khan@oracle.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
From: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup4

Due to 4e66934eaadc ("lib: add reference counting tracking
infrastructure") landing recently to net-next adding a new stack depot
user in lib/ref_tracker.c we need to add an appropriate call to
stack_depot_init() there as well.

Link: https://lkml.kernel.org/r/45c1b738-1a2f-5b5f-2f6d-86fab206d01c@suse.cz
Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jiri Slab &lt;jirislaby@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;
</content>
</entry>
<entry>
<title>lib/crypto: add prompts back to crypto libraries</title>
<updated>2022-01-18T12:03:55Z</updated>
<author>
<name>Justin M. Forbes</name>
<email>jforbes@fedoraproject.org</email>
</author>
<published>2022-01-12T14:01:38Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=e56e18985596617ae426ed5997fb2e737cffb58b'/>
<id>urn:sha1:e56e18985596617ae426ed5997fb2e737cffb58b</id>
<content type='text'>
Commit 6048fdcc5f269 ("lib/crypto: blake2s: include as built-in") took
away a number of prompt texts from other crypto libraries. This makes
values flip from built-in to module when oldconfig runs, and causes
problems when these crypto libs need to be built in for thingslike
BIG_KEYS.

Fixes: 6048fdcc5f269 ("lib/crypto: blake2s: include as built-in")
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Justin M. Forbes &lt;jforbes@fedoraproject.org&gt;
[Jason: - moved menu into submenu of lib/ instead of root menu
        - fixed chacha sub-dependencies for CONFIG_CRYPTO]
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>arch: remove GENERIC_FIND_FIRST_BIT entirely</title>
<updated>2022-01-15T16:47:31Z</updated>
<author>
<name>Yury Norov</name>
<email>yury.norov@gmail.com</email>
</author>
<published>2021-08-14T21:17:00Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=c126a53c276048125b4a950072bab37ad0fea120'/>
<id>urn:sha1:c126a53c276048125b4a950072bab37ad0fea120</id>
<content type='text'>
In 5.12 cycle we enabled GENERIC_FIND_FIRST_BIT config option for ARM64
and MIPS. It increased performance and shrunk .text size; and so far
I didn't receive any negative feedback on the change.

https://lore.kernel.org/linux-arch/20210225135700.1381396-1-yury.norov@gmail.com/

Now I think it's a good time to switch all architectures to use
find_{first,last}_bit() unconditionally, and so remove corresponding
config option.

The patch does't introduce functioal changes for arc, arm, arm64, mips,
m68k, s390 and x86, for other architectures I expect improvement both in
performance and .text size.

Signed-off-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Tested-by: Alexander Lobakin &lt;alobakin@pm.me&gt; (mips)
Reviewed-by: Alexander Lobakin &lt;alobakin@pm.me&gt; (mips)
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Acked-by: Will Deacon &lt;will@kernel.org&gt;
Tested-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
</content>
</entry>
<entry>
<title>lib: add reference counting tracking infrastructure</title>
<updated>2021-12-07T00:04:44Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-12-05T04:21:55Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=4e66934eaadc83b27ada8d42b60894018f3bfabf'/>
<id>urn:sha1:4e66934eaadc83b27ada8d42b60894018f3bfabf</id>
<content type='text'>
It can be hard to track where references are taken and released.

In networking, we have annoying issues at device or netns dismantles,
and we had various proposals to ease root causing them.

This patch adds new infrastructure pairing refcount increases
and decreases. This will self document code, because programmers
will have to associate increments/decrements.

This is controled by CONFIG_REF_TRACKER which can be selected
by users of this feature.

This adds both cpu and memory costs, and thus should probably be
used with care.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reviewed-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
</feed>
