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2021-05-06hpfs: replace one-element array with flexible-array memberGravatar Gustavo A. R. Silva 1-1/+2
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. Also, this helps with the ongoing efforts to enable -Warray-bounds by fixing the following warning: CC [M] fs/hpfs/dir.o fs/hpfs/dir.c: In function `hpfs_readdir': fs/hpfs/dir.c:163:41: warning: array subscript 1 is above array bounds of `u8[1]' {aka `unsigned char[1]'} [-Warray-bounds] 163 | || de ->name[0] != 1 || de->name[1] != 1)) | ~~~~~~~~^~~ [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/109 Link: https://lkml.kernel.org/r/20210326173510.GA81212@embeddedor Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06nilfs2: fix typos in commentsGravatar Lu Jialin 3-4/+4
numer -> number in fs/nilfs2/cpfile.c Decription -> Description in fs/nilfs2/ioctl.c isntance -> instance in fs/nilfs2/the_nilfs.c Link: https://lkml.kernel.org/r/1617942951-14631-1-git-send-email-konishi.ryusuke@gmail.com Link: https://lore.kernel.org/r/20210409022519.176988-1-lujialin4@huawei.com Signed-off-by: Lu Jialin <lujialin4@huawei.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06fs/nilfs2: fix misspellings using codespell toolGravatar Liu xuzhi 1-2/+2
Two typos are found out by codespell tool \ in 2217th and 2254th lines of segment.c: $ codespell ./fs/nilfs2/ ./segment.c:2217 :retured ==> returned ./segment.c:2254: retured ==> returned Fix two typos found by codespell. Link: https://lkml.kernel.org/r/1617864087-8198-1-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Liu xuzhi <liu.xuzhi@zte.com.cn> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06isofs: fix fall-through warnings for ClangGravatar Gustavo A. R. Silva 1-0/+1
In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning by explicitly adding a break statement instead of just letting the code fall through to the next case. Link: https://github.com/KSPP/linux/issues/115 Link: https://lkml.kernel.org/r/5b7caa73958588065fabc59032c340179b409ef5.1605896059.git.gustavoars@kernel.org Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06fs/epoll: restore waking from ep_done_scan()Gravatar Davidlohr Bueso 1-0/+6
Commit 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") changed the userspace visible behavior of exclusive waiters blocked on a common epoll descriptor upon a single event becoming ready. Previously, all tasks doing epoll_wait would awake, and now only one is awoken, potentially causing missed wakeups on applications that rely on this behavior, such as Apache Qpid. While the aforementioned commit aims at having only a wakeup single path in ep_poll_callback (with the exceptions of epoll_ctl cases), we need to restore the wakeup in what was the old ep_scan_ready_list() such that the next thread can be awoken, in a cascading style, after the waker's corresponding ep_send_events(). Link: https://lkml.kernel.org/r/20210405231025.33829-3-dave@stgolabs.net Fixes: 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll") Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Jason Baron <jbaron@akamai.com> Cc: Roman Penyaev <rpenyaev@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kselftest: introduce new epoll test caseGravatar Davidlohr Bueso 1-0/+44
Patch series "fs/epoll: restore user-visible behavior upon event ready". This series tries to address a change in user visible behavior, reported in https://bugzilla.kernel.org/show_bug.cgi?id=208943. Epoll does not report an event to all the threads running epoll_wait() on the same epoll descriptor. Unsurprisingly, this was bisected back to 339ddb53d373 (fs/epoll: remove unnecessary wakeups of nested epoll), which has had various problems in the past, beyond only nested epoll usage. This patch (of 2): This incorporates the testcase originally reported in: https://bugzilla.kernel.org/show_bug.cgi?id=208943 Which ensures an event is reported to all threads blocked on the same epoll descriptor, otherwise only a single thread will receive the wakeup once the event become ready. Link: https://lkml.kernel.org/r/20210405231025.33829-1-dave@stgolabs.net Link: https://lkml.kernel.org/r/20210405231025.33829-2-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Jason Baron <jbaron@akamai.com> Cc: Roman Penyaev <rpenyaev@suse.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06checkpatch: improve ALLOC_ARRAY_ARGS testGravatar Christophe JAILLET 1-1/+1
The devm_ variant of 'kcalloc()' and 'kmalloc_array()' are not tested Add the corresponding check. Link: https://lkml.kernel.org/r/205fc4847972fb6779abcc8818f39c14d1b45af1.1618595794.git.christophe.jaillet@wanadoo.fr Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06checkpatch: exclude four preprocessor sub-expressions from MACRO_ARG_REUSEGravatar Vincent Mailhol 1-1/+1
__must_be_array, offsetof, sizeof_field and __stringify are all preprocessor macros and do not evaluate their arguments. As such, it is safe not to warn when arguments are being reused in those four sub-expressions. Exclude those so that they can pass checkpatch. Link: https://lkml.kernel.org/r/20210407105042.25380-1-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Acked-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06checkpatch: warn when missing newline in return sysfs_emit() formatsGravatar Joe Perches 1-0/+11
return sysfs_emit() uses should include a newline. Suggest adding a newline when one is missing. Add one using --fix too. Link: https://lkml.kernel.org/r/aa1819fa5faf786573df298e5e2e7d357ba7d4ad.camel@perches.com Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06include/linux/compat.h: remove unneeded declaration from ↵Gravatar Masahiro Yamada 1-1/+0
COMPAT_SYSCALL_DEFINEx() compat_sys##name is declared twice, just one line below. With this removal SYSCALL_DEFINEx() (defined in <linux/syscalls.h>) and COMPAT_SYSCALL_DEFINEx() look symmetrical. Link: https://lkml.kernel.org/r/20210223114924.854794-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: parser: clean up kernel-docGravatar Randy Dunlap 1-23/+38
Mark match_uint() as kernel-doc notation since it is already fully annotated as such. Use % prefix on constants in kernel-doc comments. Convert function return descriptions to use the "Return:" kernel-doc notation. Link: https://lkml.kernel.org/r/20210407034514.5651-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib/genalloc: add parameter description to fix doc compile warningGravatar Alex Shi 1-0/+5
Commit 52fbf1134d47 ("lib/genalloc.c: fix allocation of aligned buffer from non-aligned chunk") added a new parameter 'start_addr' w/o description for it. That causes some doc compile warning: lib/genalloc.c:649: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit' lib/genalloc.c:667: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit_align' lib/genalloc.c:694: warning: Function parameter or member 'start_addr' not described in 'gen_pool_fixed_alloc' lib/genalloc.c:729: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit_order_align' lib/genalloc.c:752: warning: Function parameter or member 'start_addr' not described in 'gen_pool_best_fit' This fixes it by adding a parameter descriptions. Link: https://lkml.kernel.org/r/20210405132021.131231-1-alexs@kernel.org Signed-off-by: Alex Shi <alexs@kernel.org> Cc: Alexey Skidanov <alexey.skidanov@intel.com> Cc: Huang Shijie <sjhuang@iluvatar.ai> Cc: Alex Shi <alexs@kernel.org> Cc: Bhaskar Chowdhury <unixbhaskar@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib/percpu_counter: tame kernel-doc compile warningGravatar Alex Shi 1-1/+1
commit 3e8f399da490 ("writeback: rework wb_[dec|inc]_stat family of functions") add some function description of percpu_counter_add_batch. but the double '*' in comments means a kernel-doc format comment which isn't right. Since the whole file of lib/percpu_counter.c has no any other kernel-doc format comments, we'd better to remove this incomplete one to tame the kernel-doc warning: lib/percpu_counter.c:83: warning: Function parameter or member 'fbc' not described in 'percpu_counter_add_batch' lib/percpu_counter.c:83: warning: Function parameter or member 'amount' not described in 'percpu_counter_add_batch' lib/percpu_counter.c:83: warning: Function parameter or member 'batch' not described in 'percpu_counter_add_batch' Link: https://lkml.kernel.org/r/20210405135505.132446-1-alexs@kernel.org Signed-off-by: Alex Shi <alexs@kernel.org> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: stackdepot: turn depot_lock spinlock to raw_spinlockGravatar Zqiang 1-3/+3
In RT system, the spin_lock will be replaced by sleepable rt_mutex lock, in __call_rcu(), disable interrupts before calling kasan_record_aux_stack(), will trigger this calltrace: BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:951 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 19, name: pgdatinit0 Call Trace: ___might_sleep.cold+0x1b2/0x1f1 rt_spin_lock+0x3b/0xb0 stack_depot_save+0x1b9/0x440 kasan_save_stack+0x32/0x40 kasan_record_aux_stack+0xa5/0xb0 __call_rcu+0x117/0x880 __exit_signal+0xafb/0x1180 release_task+0x1d6/0x480 exit_notify+0x303/0x750 do_exit+0x678/0xcf0 kthread+0x364/0x4f0 ret_from_fork+0x22/0x30 Replace spinlock with raw_spinlock. Link: https://lkml.kernel.org/r/20210329084009.27013-1-qiang.zhang@windriver.com Signed-off-by: Zqiang <qiang.zhang@windriver.com> Reported-by: Andrew Halaney <ahalaney@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Yogesh Lal <ylal@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: crc8: pointer to data block should be constGravatar Richard Fitzgerald 2-2/+2
crc8() does not change the data passed to it, so the pointer argument should be declared const. This avoids callers that receive const data having to cast it to a non-const pointer to call crc8(). Link: https://lkml.kernel.org/r/20210329122409.3291-1-rf@opensource.cirrus.com Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib/genalloc.c: Fix a typoGravatar Bhaskar Chowdhury 1-1/+1
s/macthing/matching/ Link: https://lkml.kernel.org/r/20210326131530.30481-1-unixbhaskar@gmail.com Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib/list_sort.c: fix typo in function descriptionGravatar ToastC 1-1/+1
Replace beautiully with beautifully Link: https://lkml.kernel.org/r/20210315090633.9759-1-mrtoastcheng@gmail.com Signed-off-by: ShihCheng Tu <mrtoastcheng@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: fix inconsistent indenting in process_bit1()Gravatar Wang Qing 1-1/+1
Smatch gives the warning: lib/decompress_unlzma.c:395 process_bit1() warn: inconsistent indenting Link: https://lkml.kernel.org/r/1614567775-4478-1-git-send-email-wangqing@vivo.com Signed-off-by: Wang Qing <wangqing@vivo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib/bch.c: fix a typo in the file bch.cGravatar Bhaskar Chowdhury 1-1/+1
s/buid/build/ Link: https://lkml.kernel.org/r/20210301123129.18754-1-unixbhaskar@gmail.com Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06MAINTAINERS: add entry for the bitmap APIGravatar Yury Norov 1-0/+16
Add myself as maintainer for bitmap API and Andy and Rasmus as reviewers. Link: https://lkml.kernel.org/r/20210401003153.97325-13-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: sync lib/find_bit implementationGravatar Yury Norov 2-5/+57
Add fast paths to find_*_bit() functions as per kernel implementation. Link: https://lkml.kernel.org/r/20210401003153.97325-12-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: add fast path for find_first_*_bit() and find_last_bit()Gravatar Yury Norov 3-22/+52
Similarly to bitmap functions, users would benefit if we'll handle a case of small-size bitmaps that fit into a single word. While here, move the find_last_bit() declaration to bitops/find.h where other find_*_bit() functions sit. Link: https://lkml.kernel.org/r/20210401003153.97325-11-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: add fast path for find_next_*_bit()Gravatar Yury Norov 2-0/+51
Similarly to bitmap functions, find_next_*_bit() users will benefit if we'll handle a case of bitmaps that fit into a single word inline. In the very best case, the compiler may replace a function call with a few instructions. This is the quite typical find_next_bit() user: unsigned int cpumask_next(int n, const struct cpumask *srcp) { /* -1 is a legal arg here. */ if (n != -1) cpumask_check(n); return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1); } EXPORT_SYMBOL(cpumask_next); Currently, on ARM64 the generated code looks like this: 0000000000000000 <cpumask_next>: 0: a9bf7bfd stp x29, x30, [sp, #-16]! 4: 11000402 add w2, w0, #0x1 8: aa0103e0 mov x0, x1 c: d2800401 mov x1, #0x40 // #64 10: 910003fd mov x29, sp 14: 93407c42 sxtw x2, w2 18: 94000000 bl 0 <find_next_bit> 1c: a8c17bfd ldp x29, x30, [sp], #16 20: d65f03c0 ret 24: d503201f nop After applying this patch: 0000000000000140 <cpumask_next>: 140: 11000400 add w0, w0, #0x1 144: 93407c00 sxtw x0, w0 148: f100fc1f cmp x0, #0x3f 14c: 54000168 b.hi 178 <cpumask_next+0x38> // b.pmore 150: f9400023 ldr x3, [x1] 154: 92800001 mov x1, #0xffffffffffffffff // #-1 158: 9ac02020 lsl x0, x1, x0 15c: 52800802 mov w2, #0x40 // #64 160: 8a030001 and x1, x0, x3 164: dac00020 rbit x0, x1 168: f100003f cmp x1, #0x0 16c: dac01000 clz x0, x0 170: 1a800040 csel w0, w2, w0, eq // eq = none 174: d65f03c0 ret 178: 52800800 mov w0, #0x40 // #64 17c: d65f03c0 ret find_next_bit() call is replaced with 6 instructions. find_next_bit() itself is 41 instructions plus function call overhead. Despite inlining, the scripts/bloat-o-meter report smaller .text size after applying the series: add/remove: 11/9 grow/shrink: 233/176 up/down: 5780/-6768 (-988) Link: https://lkml.kernel.org/r/20210401003153.97325-10-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: sync find_next_bit implementationGravatar Yury Norov 2-37/+42
Sync the implementation with recent kernel changes. Link: https://lkml.kernel.org/r/20210401003153.97325-9-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: inline _find_next_bit() wrappersGravatar Yury Norov 3-64/+37
lib/find_bit.c declares five single-line wrappers for _find_next_bit(). We may turn those wrappers to inline functions. It eliminates unneeded function calls and opens room for compile-time optimizations. Link: https://lkml.kernel.org/r/20210401003153.97325-8-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: sync small_const_nbits() macro with the kernelGravatar Yury Norov 2-3/+3
Sync implementation with the kernel and move the macro from tools/include/linux/bitmap.h to tools/include/asm-generic/bitsperlong.h Link: https://lkml.kernel.org/r/20210401003153.97325-7-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06lib: extend the scope of small_const_nbits() macroGravatar Yury Norov 2-8/+12
find_bit would also benefit from small_const_nbits() optimizations. The detailed comment is provided by Rasmus Villemoes. Link: https://lkml.kernel.org/r/20210401003153.97325-6-yury.norov@gmail.com Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06arch: rearrange headers inclusion order in asm/bitops for m68k, sh and h8300Gravatar Yury Norov 3-9/+10
m68k and sh include bitmap/{find,le}.h prior to ffs/fls headers. New fast-path implementation in find.h requires ffs/fls. Reordering the headers inclusion sequence helps to prevent compile-time implicit function declaration error. [yury.norov@gmail.com: h8300: rearrange headers inclusion order in asm/bitops] Link: https://lkml.kernel.org/r/20210406183625.794227-1-yury.norov@gmail.com Link: https://lkml.kernel.org/r/20210401003153.97325-5-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: sync BITMAP_LAST_WORD_MASK() macro with the kernelGravatar Yury Norov 1-6/+1
Kernel version generates better code. Link: https://lkml.kernel.org/r/20210401003153.97325-4-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: bitmap: sync function declarations with the kernelGravatar Yury Norov 2-6/+6
Some functions in tools/include/linux/bitmap.h declare nbits as int. In the kernel nbits is declared as unsigned int. Link: https://lkml.kernel.org/r/20210401003153.97325-3-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06tools: disable -Wno-type-limitsGravatar Yury Norov 1-0/+1
Patch series "lib/find_bit: fast path for small bitmaps", v6. Bitmap operations are much simpler and faster in case of small bitmaps which fit into a single word. In linux/bitmap.c we have a machinery that allows compiler to replace actual function call with a few instructions if bitmaps passed into the function are small and their size is known at compile time. find_*_bit() API lacks this functionality; but users will benefit from it a lot. One important example is cpumask subsystem when NR_CPUS <= BITS_PER_LONG. This patch (of 12): GENMASK(h, l) may be passed with unsigned types. In such case, type-limits warning is generated for example in case of GENMASK(h, 0). Link: https://lkml.kernel.org/r/20210401003153.97325-1-yury.norov@gmail.com Link: https://lkml.kernel.org/r/20210401003153.97325-2-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Alexey Klimov <aklimov@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Sterba <dsterba@suse.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jianpeng Ma <jianpeng.ma@intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/cred.c: make init_groups staticGravatar Rasmus Villemoes 3-3/+1
init_groups is declared in both cred.h and init_task.h, but it is not actually referenced anywhere outside of cred.c where it is defined. So make it static and remove the declarations. Link: https://lkml.kernel.org/r/20210310220102.2484201-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/async.c: fix pr_debug statementGravatar Rasmus Villemoes 1-1/+1
An async_func_t returns void - any errors encountered it has to stash somewhere for consumers to discover later. Link: https://lkml.kernel.org/r/20210226124355.2503524-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06linux/profile.h: remove unnecessary declarationGravatar Wan Jiabing 1-3/+0
Declaring struct pt_regs is unnecessary. On the one hand, there is no function using it; on the other hand, struct pt_regs has been declared in linux/kernel.h. Remove them. Link: https://lkml.kernel.org/r/20210401104834.1009157-1-wanjiabing@vivo.com Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel.h: drop inclusion in bitmap.hGravatar Andy Shevchenko 3-9/+18
The bitmap.h header is used in a lot of code around the kernel. Besides that it includes kernel.h which sometimes makes a loop. The problem here is many unneeded loops that make header hell dependencies. For example, how may you move bitmap_zalloc() from C-file to the header? Currently it's impossible. And bitmap.h here is only the tip of an iceberg. kerne.h is a dump of everything that even has nothing in common at all. We may still have it, but in my new code I prefer to include only the headers that I want to use, without the bulk of unneeded kernel code. Break the loop by introducing align.h, including it in kernel.h and bitmap.h followed by replacing kernel.h with limits.h. Link: https://lkml.kernel.org/r/20210326170347.37441-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Yury Norov <yury.norov@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06include: remove pagemap.h from blkdev.hGravatar Matthew Wilcox (Oracle) 9-1/+8
My UEK-derived config has 1030 files depending on pagemap.h before this change. Afterwards, just 326 files need to be rebuilt when I touch pagemap.h. I think blkdev.h is probably included too widely, but untangling that dependency is harder and this solves my problem. x86 allmodconfig builds, but there may be implicit include problems on other architectures. Link: https://lkml.kernel.org/r/20210309195747.283796-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Dan Williams <dan.j.williams@intel.com> [nvdimm] Acked-by: Jens Axboe <axboe@kernel.dk> [block] Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: Martin K. Petersen <martin.petersen@oracle.com> [scsi] Reviewed-by: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06proc/sysctl: fix function name error in commentsGravatar zhouchuangao 1-1/+1
The function name should be modified to register_sysctl_paths instead of register_sysctl_table_path. Link: https://lkml.kernel.org/r/1615807194-79646-1-git-send-email-zhouchuangao@vivo.com Signed-off-by: zhouchuangao <zhouchuangao@vivo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06selftests: proc: test subset=pidGravatar Alexey Dobriyan 2-0/+122
Test that /proc instance mounted with mount -t proc -o subset=pid contains only ".", "..", "self", "thread-self" and pid directories. Note: Currently "subset=pid" doesn't return "." and ".." via readdir. This must be a bug. Link: https://lkml.kernel.org/r/YFYZZ7WGaZlsnChS@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06proc: delete redundant subset=pid checkGravatar Alexey Dobriyan 1-4/+0
Two checks in lookup and readdir code should be enough to not have third check in open code. Can't open what can't be looked up? Link: https://lkml.kernel.org/r/YFYYwIBIkytqnkxP@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06proc: mandate ->proc_lseek in "struct proc_ops"Gravatar Alexey Dobriyan 6-13/+9
Now that proc_ops are separate from file_operations and other operations it easy to check all instances to have ->proc_lseek hook and remove check in main code. Note: nonseekable_open() files naturally don't require ->proc_lseek. Garbage collect pde_lseek() function. [adobriyan@gmail.com: smoke test lseek()] Link: https://lkml.kernel.org/r/YG4OIhChOrVTPgdN@localhost.localdomain Link: https://lkml.kernel.org/r/YFYX0Bzwxlc7aBa/@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06proc: save LOC in __xlate_proc_name()Gravatar Alexey Dobriyan 1-9/+2
Can't look at this verbosity anymore. Link: https://lkml.kernel.org/r/YFYXAp/fgq405qcy@localhost.localdomain Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06fs/proc/generic.c: fix incorrect pde_is_permanent checkGravatar Colin Ian King 1-1/+1
Currently the pde_is_permanent() check is being run on root multiple times rather than on the next proc directory entry. This looks like a copy-paste error. Fix this by replacing root with next. Addresses-Coverity: ("Copy-paste error") Link: https://lkml.kernel.org/r/20210318122633.14222-1-colin.king@canonical.com Fixes: d919b33dafb3 ("proc: faster open/read/close with "permanent" files") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Greg Kroah-Hartman <gregkh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06alpha: csum_partial_copy.c: add function prototypes from <net/checksum.h>Gravatar Randy Dunlap 1-0/+1
Fix "no previous prototype" W=1 warnings from the kernel test robot: arch/alpha/lib/csum_partial_copy.c:349:1: error: no previous prototype for 'csum_and_copy_from_user' [-Werror=missing-prototypes] 349 | csum_and_copy_from_user(const void __user *src, void *dst, int len) | ^~~~~~~~~~~~~~~~~~~~~~~ arch/alpha/lib/csum_partial_copy.c:358:1: error: no previous prototype for 'csum_partial_copy_nocheck' [-Werror=missing-prototypes] 358 | csum_partial_copy_nocheck(const void *src, void *dst, int len) | ^~~~~~~~~~~~~~~~~~~~~~~~~ Link: https://lkml.kernel.org/r/20210425235749.19113-1-rdunlap@infradead.org Fixes: 808b49da54e6 ("alpha: turn csum_partial_copy_from_user() into csum_and_copy_from_user()") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06alpha: eliminate old-style function definitionsGravatar Randy Dunlap 1-2/+2
'make ARCH=alpha W=1' reports a couple of old-style function definitions with missing parameter list, so fix those. arch/alpha/kernel/pc873xx.c: In function 'pc873xx_get_base': arch/alpha/kernel/pc873xx.c:16:21: warning: old-style function definition [-Wold-style-definition] 16 | unsigned int __init pc873xx_get_base() arch/alpha/kernel/pc873xx.c: In function 'pc873xx_get_model': arch/alpha/kernel/pc873xx.c:21:14: warning: old-style function definition [-Wold-style-definition] 21 | char *__init pc873xx_get_model() Link: https://lkml.kernel.org/r/20210421061312.30097-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05kfence: use power-efficient work queue to run delayed workGravatar Marco Elver 1-2/+3
Use the power-efficient work queue, to avoid the pathological case where we keep pinning ourselves on the same possibly idle CPU on systems that want to be power-efficient (https://lwn.net/Articles/731052/). Link: https://lkml.kernel.org/r/20210421105132.3965998-4-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Jann Horn <jannh@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05kfence: maximize allocation wait timeout durationGravatar Marco Elver 1-1/+11
The allocation wait timeout was initially added because of warnings due to CONFIG_DETECT_HUNG_TASK=y [1]. While the 1 sec timeout is sufficient to resolve the warnings (given the hung task timeout must be 1 sec or larger) it may cause unnecessary wake-ups if the system is idle: https://lkml.kernel.org/r/CADYN=9J0DQhizAGB0-jz4HOBBh+05kMBXb4c0cXMS7Qi5NAJiw@mail.gmail.com Fix it by computing the timeout duration in terms of the current sysctl_hung_task_timeout_secs value. Link: https://lkml.kernel.org/r/20210421105132.3965998-3-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Jann Horn <jannh@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05kfence: await for allocation using wait_eventGravatar Marco Elver 2-16/+30
Patch series "kfence: optimize timer scheduling", v2. We have observed that mostly-idle systems with KFENCE enabled wake up otherwise idle CPUs, preventing such to enter a lower power state. Debugging revealed that KFENCE spends too much active time in toggle_allocation_gate(). While the first version of KFENCE was using all the right bits to be scheduling optimal, and thus power efficient, by simply using wait_event() + wake_up(), that code was unfortunately removed. As KFENCE was exposed to various different configs and tests, the scheduling optimal code slowly disappeared. First because of hung task warnings, and finally because of deadlocks when an allocation is made by timer code with debug objects enabled. Clearly, the "fixes" were not too friendly for devices that want to be power efficient. Therefore, let's try a little harder to fix the hung task and deadlock problems that we have with wait_event() + wake_up(), while remaining as scheduling friendly and power efficient as possible. Crucially, we need to defer the wake_up() to an irq_work, avoiding any potential for deadlock. The result with this series is that on the devices where we observed a power regression, power usage returns back to baseline levels. This patch (of 3): On mostly-idle systems, we have observed that toggle_allocation_gate() is a cause of frequent wake-ups, preventing an otherwise idle CPU to go into a lower power state. A late change in KFENCE's development, due to a potential deadlock [1], required changing the scheduling-friendly wait_event_timeout() and wake_up() to an open-coded wait-loop using schedule_timeout(). [1] https://lkml.kernel.org/r/000000000000c0645805b7f982e4@google.com To avoid unnecessary wake-ups, switch to using wait_event_timeout(). Unfortunately, we still cannot use a version with direct wake_up() in __kfence_alloc() due to the same potential for deadlock as in [1]. Instead, add a level of indirection via an irq_work that is scheduled if we determine that the kfence_timer requires a wake_up(). Link: https://lkml.kernel.org/r/20210421105132.3965998-1-elver@google.com Link: https://lkml.kernel.org/r/20210421105132.3965998-2-elver@google.com Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jann Horn <jannh@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Hillf Danton <hdanton@sina.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05kfence: zero guard page after out-of-bounds accessGravatar Marco Elver 1-0/+1
After an out-of-bounds accesses, zero the guard page before re-protecting in kfence_guarded_free(). On one hand this helps make the failure mode of subsequent out-of-bounds accesses more deterministic, but could also prevent certain information leaks. Link: https://lkml.kernel.org/r/20210312121653.348518-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Acked-by: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05mm/process_vm_access.c: remove duplicate includeGravatar Zhang Yunkai 1-1/+0
'linux/compat.h' included in 'process_vm_access.c' is duplicated. Link: https://lkml.kernel.org/r/20210306132122.220431-1-zhang.yunkai@zte.com.cn Signed-off-by: Zhang Yunkai <zhang.yunkai@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05mm/mempool: minor coding style tweaksGravatar Zhiyuan Dai 14-23/+27
Various coding style tweaks to various files under mm/ [daizhiyuan@phytium.com.cn: mm/swapfile: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614223624-16055-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/sparse: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614227288-19363-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/vmscan: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614227649-19853-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/compaction: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614228218-20770-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/oom_kill: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614228360-21168-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/shmem: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614228504-21491-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/page_alloc: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614228613-21754-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/filemap: minor coding style tweaks] Link: https://lkml.kernel.org/r/1614228936-22337-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/mlock: minor coding style tweaks] Link: https://lkml.kernel.org/r/1613956588-2453-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/frontswap: minor coding style tweaks] Link: https://lkml.kernel.org/r/1613962668-15045-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/vmalloc: minor coding style tweaks] Link: https://lkml.kernel.org/r/1613963379-15988-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/memory_hotplug: minor coding style tweaks] Link: https://lkml.kernel.org/r/1613971784-24878-1-git-send-email-daizhiyuan@phytium.com.cn [daizhiyuan@phytium.com.cn: mm/mempolicy: minor coding style tweaks] Link: https://lkml.kernel.org/r/1613972228-25501-1-git-send-email-daizhiyuan@phytium.com.cn Link: https://lkml.kernel.org/r/1614222374-13805-1-git-send-email-daizhiyuan@phytium.com.cn Signed-off-by: Zhiyuan Dai <daizhiyuan@phytium.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>