In workloads where this_cpu operations are frequently performed,
enabling DEBUG_PREEMPT may result in significant increase in
runtime overhead due to frequent invocation of
__this_cpu_preempt_check() function.
This can be demonstrated through benchmarks such as hackbench where this
configuration results in a 10% reduction in performance, primarily due to
the added overhead within memcg charging path.
Therefore, do not to enable DEBUG_PREEMPT by default and make users aware
of its potential impact on performance in some workloads.
hackbench-process-sockets
debug_preempt no_debug_preempt
Amean 1 0.4743 ( 0.00%) 0.4295 * 9.45%*
Amean 4 1.4191 ( 0.00%) 1.2650 * 10.86%*
Amean 7 2.2677 ( 0.00%) 2.0094 * 11.39%*
Amean 12 3.6821 ( 0.00%) 3.2115 * 12.78%*
Amean 21 6.6752 ( 0.00%) 5.7956 * 13.18%*
Amean 30 9.6646 ( 0.00%) 8.5197 * 11.85%*
Amean 48 15.3363 ( 0.00%) 13.5559 * 11.61%*
Amean 79 24.8603 ( 0.00%) 22.0597 * 11.27%*
Amean 96 30.1240 ( 0.00%) 26.8073 * 11.01%*
Link: https://lkml.kernel.org/r/20230121033942.350387-1-42.hyeyoo@gmail.com
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ben Segall <bsegall@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since hardware inflate does not support Z_PACKET_FLUSH option (used
exclusively by kernel PPP driver), always switch to software like we
already do for Z_BLOCK flush option. Without this patch, PPP might get
Z_DATA_ERROR return code from zlib_inflate() and disable zlib compression
for the packets.
Link: https://lkml.kernel.org/r/20230126131428.1222214-9-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There is no hardware control for DFLTCC window size. After this change,
software and hardware window formats no longer match: the software will
use wbits and wsize, and the hardware will use HB_BITS and HB_SIZE.
Since neither dictionary manipulation nor internal allocation functions
are relevant to kernel zlib and zlib_inflate_workspacesize() always use
MAX_WBITS for window size calculation, only dfltcc_can_inflate() and
dfltcc_inflate() functions are affected by this patch.
This commit is based on:
https://github.com/zlib-ng/zlib-ng/commit/3eab317
Link: https://lkml.kernel.org/r/20230126131428.1222214-8-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently deflate and inflate both use a common state struct. There are
several variables in this struct that we don't need for inflate, and
more may be coming in the future. Therefore split them in two separate
structs.
Apart from that, introduce separate headers for dfltcc_deflate and
dfltcc_inflate.
This commit is based on:
https://github.com/zlib-ng/zlib-ng/commit/c592b1b
Link: https://lkml.kernel.org/r/20230126131428.1222214-7-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "lib/zlib: Set of s390 DFLTCC related patches for kernel zlib".
Patches 1-7 represent a set of s390 zlib hardware support (DFLTCC) related
fixes and enhancements integrated from zlib-ng repo relevant to kernel
zlib (https://github.com/zlib-ng/zlib-ng).
Since the official zlib repository never got DFLTCC support code merged,
all the patches have been picked from zlib-ng fork (zlib data compression
library for the next generation systems). This repo contains new
optimizations and fixes not getting implemented into the official zlib
repository and falls under the same zlib License. All of the original
patches from zlib-ng were authored by Ilya Leoshkevich
<iii@linux.ibm.com>. Coding style has been preserved for future
maintainability.
Patches 1-2 should have no effect for the kernel zlib but make the code
closer to zlib-ng for future maintainability.
Only Patch 3 touches common zlib_deflate code, other patches are relevant
to s390 tree only.
Patch 8 is separate and intends to resolve an issue with kernel PPP driver
which can use kernel zlib for packet compression. Without this patch PPP
decompression can fail due to error code returned by hardware
(dfltcc_inflate) and PPP disables zlib compression for further packets.
This patch (of 8):
This commit is based on:
https://github.com/zlib-ng/zlib-ng/commit/d8b67f5
Link: https://lkml.kernel.org/r/20230126131428.1222214-1-zaslonko@linux.ibm.com
Link: https://lkml.kernel.org/r/20230126131428.1222214-2-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com> (s390)
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If DAT metadata file block access fails due to corruption of the DAT file
or abnormal virtual block numbers held by b-trees or inodes, a kernel
warning is generated.
This replaces the WARN_ONs by error output, so that a kernel, booted with
panic_on_warn, does not panic. This patch also replaces the detected
return code -ENOENT with another internal code -EINVAL to notify the bmap
layer of metadata corruption. When the bmap layer sees -EINVAL, it
handles the abnormal situation with nilfs_bmap_convert_error() and finally
returns code -EIO as it should.
Link: https://lkml.kernel.org/r/0000000000005cc3d205ea23ddcf@google.com
Link: https://lkml.kernel.org/r/20230126164114.6911-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: <syzbot+5d5d25f90f195a3cfcb4@syzkaller.appspotmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When filesystem's ->get_block function does not map the buffer head when
called from __mpage_writepage(), __mpage_writepage() will happily go and
pass bogus bdev and block number to bio allocation routines which leads to
crashes sooner or later.
E.g. UDF can do this because it doesn't want to allocate blocks from
->writepages callbacks. It allocates blocks on write or page fault but
writeback can still spot dirty buffers without underlying blocks allocated
e.g. if blocksize < pagesize, the tail page is dirtied (which means all
its buffers are dirtied), and truncate extends the file so that some
buffer starts to be within i_size.
Link: https://lkml.kernel.org/r/20230126085155.26395-1-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Privately, Heinz Mauelshagen showed that the embedded filename test is not
specific enough.
> WARNING: It's generally not useful to have the filename in the file
> #113: FILE: errors.c:113:
> + block < registered_errors.blocks + registered_errors.count;
Extend the test to use the appropriate word boundary tests.
Link: https://lkml.kernel.org/r/36069dac5d07509dab1c7f1238f8cbb08db80ac6.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
ext4_update_bh_state. x86 CMPXCHG instruction returns success in ZF flag,
so this change saves a compare after cmpxchg (and related move instruction
in front of cmpxchg).
Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails. There is no need to re-read the value in the loop.
No functional change intended.
Link: https://lkml.kernel.org/r/20221102071147.6642-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When aops->write_begin() does not initialize fsdata, KMSAN may report an
error passing the latter to aops->write_end().
Fix this by unconditionally initializing fsdata.
Link: https://lkml.kernel.org/r/20221121112134.407362-5-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Chao Yu <chao@kernel.org>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When aops->write_begin() does not initialize fsdata, KMSAN may report an
error passing the latter to aops->write_end().
Fix this by unconditionally initializing fsdata.
Link: https://lkml.kernel.org/r/20221121112134.407362-4-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Chao Yu <chao@kernel.org>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Current Debian lintian tool flagged several (more) spelling errors, so
add them so they can hopefully be prevented in the future.
Link: https://lkml.kernel.org/r/20230122173256.52280-1-didi.debian@cknow.org
Signed-off-by: Diederik de Haas <didi.debian@cknow.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Instead of using an unnecessarily complicated approach to print a line
that is warned about, use `$herecurr` instead, just like everywhere else
in checkpatch.
While at it, remove a superfluous space in one of the changed lines, too.
In a unmodified line also remove a superfluous check for a space before a
signed-off-by tag, to me consistent with the check at the start of the
section.
All three problems were found by Joe Perches during review of new code
inspired by the code modified here.
Link: https://lkml.kernel.org/r/a6d455c5196219b2095c2ac3645498052845f32e.1674217480.git.linux@leemhuis.info
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Wasserbäch <kai@dev.carbon-project.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Encourage patch authors to link to reports by issuing a warning, if a
Reported-by: is not accompanied by a link to the report. Those links are
often extremely useful for any code archaeologist that wants to know more
about the backstory of a change than the commit message provides. That
includes maintainers higher up in the patch-flow hierarchy, which is why
Linus asks developers to add such links [1, 2, 3]. To quote [1]:
> Again, the commit has a link to the patch *submission*, which is
> almost entirely useless. There's no link to the actual problem the
> patch fixes.
>
> [...]
>
> Put another way: I can see that
>
> Reported-by: Zhangfei Gao <zhangfei.gao@foxmail.com>
>
> in the commit, but I don't have a clue what the actual report was, and
> there really isn't enough information in the commit itself, except for
> a fairly handwavy "Device drivers might, for instance, still need to
> flush operations.."
>
> I don't want to know what device drivers _might_ do. I would want to
> have an actual pointer to what they do and where.
Another reason why these links are wanted: the ongoing regression tracking
efforts can only scale with them, as they allow the regression tracking
bot 'regzbot' to automatically connect tracked reports with patches that
are posted or committed to fix tracked regressions.
Link: https://lore.kernel.org/all/CAHk-=wjMmSZzMJ3Xnskdg4+GGz=5p5p+GSYyFBTh0f-DgvdBWg@mail.gmail.com/ [1]
Link: https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@mail.gmail.com/ [2]
Link: https://lore.kernel.org/all/CAHk-=wjxzafG-=J8oT30s7upn4RhBs6TX-uVFZ5rME+L5_DoJA@mail.gmail.com/ [3]
Link: https://lkml.kernel.org/r/bb5dfd55ea2026303ab2296f4a6df3da7dd64006.1674217480.git.linux@leemhuis.info
Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Co-developed-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "checkpatch.pl: warn about discouraged tags and missing Link:
tags", v4.
The first two changes make checkpatch.pl check for a few mistakes wrt to
links to bug reports Linus recently complained about a few times.
Avoiding those is also important for my regression tracking efforts a lot,
as the automated tracking performed by regzbot relies on the proper usage
of the Link: tag.
The third patch fixes a few small oddities noticed in existing code during
review of the two changes.
This patch (of 3):
Issue a warning when encountering URLs behind unknown tags, as Linus
recently stated ```please stop making up random tags that make no sense.
Just use "Link:"```[1]. That statement was triggered by an use of
'BugLink', but that's not the only tag people invented:
$ git log -100000 --no-merges --format=email -P \
--grep='^\w+:[ ]*http' | grep -Poh '^\w+:[ ]*http' | \
sort | uniq -c | sort -rn | head -n 20
103958 Link: http
418 BugLink: http
372 Patchwork: http
280 Closes: http
224 Bug: http
123 References: http
84 Bugzilla: http
61 URL: http
42 v1: http
38 Datasheet: http
20 v2: http
9 Ref: http
9 Fixes: http
9 Buglink: http
8 v3: http
8 Reference: http
7 See: http
6 1: http
5 link: http
3 Link:http
Some of these non-standard tags make it harder for external tools that
rely on use of proper tags. One of those tools is the regression tracking
bot 'regzbot', which looks out for "Link:" tags pointing to reports of
tracked regressions.
The initial idea was to use a disallow list to raise an error when
encountering known unwanted tags like BugLink:; during review it was
requested to use a list of allowed tags instead[2].
Link: https://lkml.kernel.org/r/cover.1674217480.git.linux@leemhuis.info
Link: https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@mail.gmail.com/ [1]
Link: https://lore.kernel.org/all/15f7df96d49082fb7799dda6e187b33c84f38831.camel@perches.com/ [2]
Link: https://lkml.kernel.org/r/3b036087d80b8c0e07a46a1dbaaf4ad0d018f8d5.1674217480.git.linux@leemhuis.info
Signed-off-by: Kai Wasserbäch <kai@dev.carbon-project.org>
Co-developed-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
{set,clear}_bits_ll. x86 CMPXCHG instruction returns success in ZF flag,
so this change saves a compare after cmpxchg (and related move instruction
in front of cmpxchg).
Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails.
Note that the value from *ptr should be read using READ_ONCE to prevent
the compiler from merging, refetching or reordering the read.
The patch also declares these two functions inline, to ensure inlining.
No functional change intended.
Link: https://lkml.kernel.org/r/20230118150703.4024-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
strtobool() is the same as kstrtobool(). However, the latter is more used
within the kernel.
In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.
While at it, include the corresponding header file (<linux/kstrtox.h>)
Link: https://lkml.kernel.org/r/2597e80cb7059ec6ad63a01b77d7c944dcc99195.1673716768.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Disseldorp <ddiss@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Martin Wilck <mwilck@suse.com>
Cc: wuchi <wuchi.zero@gmail.com>
Cc: XU pengfei <xupengfei@nfschina.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
kexec allows replacing the current kernel with a different one. This is
usually a source of concerns for sysadmins that want to harden a system.
Linux already provides a way to disable loading new kexec kernel via
kexec_load_disabled, but that control is very coard, it is all or nothing
and does not make distinction between a panic kexec and a normal kexec.
This patch introduces new sysctl parameters, with finer tuning to specify
how many times a kexec kernel can be loaded. The sysadmin can set
different limits for kexec panic and kexec reboot kernels. The value can
be modified at runtime via sysctl, but only with a stricter value.
With these new parameters on place, a system with loadpin and verity
enabled, using the following kernel parameters:
sysctl.kexec_load_limit_reboot=0 sysct.kexec_load_limit_panic=1 can have a
good warranty that if initrd tries to load a panic kernel, a malitious
user will have small chances to replace that kernel with a different one,
even if they can trigger timeouts on the disk where the panic kernel
lives.
Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-3-6a8531a09b9a@chromium.org
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Philipp Rudo <prudo@redhat.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Both syscalls (kexec and kexec_file) do the same check, let's factor it
out.
Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-2-6a8531a09b9a@chromium.org
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Guilherme G. Piccoli <gpiccoli@igalia.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Philipp Rudo <prudo@redhat.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "kexec: Add new parameter to limit the access to kexec", v6.
Add two parameter to specify how many times a kexec kernel can be loaded.
These parameter allow hardening the system.
While we are at it, fix a documentation issue and refactor some code.
This patch (of 3):
kexec_load_disabled affects both ``kexec_load`` and ``kexec_file_load``
syscalls. Make it explicit.
Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-0-6a8531a09b9a@chromium.org
Link: https://lkml.kernel.org/r/20221114-disable-kexec-reset-v6-1-6a8531a09b9a@chromium.org
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Guilherme G. Piccoli <gpiccoli@igalia.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Philipp Rudo <prudo@redhat.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the 'struct' keyword for a struct's kernel-doc notation to avoid a
kernel-doc warning:
kernel/user_namespace.c:232: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* idmap_key struct holds the information necessary to find an idmapping in a
Link: https://lkml.kernel.org/r/20230108021243.16683-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix many W=1 kernel-doc warnings in fs/ntfs/:
fs/ntfs/aops.c:30: warning: Incorrect use of kernel-doc format: * ntfs_end_buffer_async_read - async io completion for reading attributes
fs/ntfs/aops.c:46: warning: expecting prototype for aops.c(). Prototype was for ntfs_end_buffer_async_read() instead
fs/ntfs/aops.c:1655: warning: cannot understand function prototype: 'const struct address_space_operations ntfs_normal_aops = '
fs/ntfs/aops.c:1670: warning: cannot understand function prototype: 'const struct address_space_operations ntfs_compressed_aops = '
fs/ntfs/aops.c:1685: warning: cannot understand function prototype: 'const struct address_space_operations ntfs_mst_aops = '
fs/ntfs/compress.c:22: warning: Incorrect use of kernel-doc format: * ntfs_compression_constants - enum of constants used in the compression code
fs/ntfs/compress.c:24: warning: cannot understand function prototype: 'typedef enum '
fs/ntfs/compress.c:47: warning: cannot understand function prototype: 'u8 *ntfs_compression_buffer; '
fs/ntfs/compress.c:52: warning: expecting prototype for ntfs_cb_lock(). Prototype was for DEFINE_SPINLOCK() instead
fs/ntfs/dir.c:21: warning: Incorrect use of kernel-doc format: * The little endian Unicode string $I30 as a global constant.
fs/ntfs/dir.c:23: warning: cannot understand function prototype: 'ntfschar I30[5] = '
fs/ntfs/inode.c:31: warning: Incorrect use of kernel-doc format: * ntfs_test_inode - compare two (possibly fake) inodes for equality
fs/ntfs/inode.c:47: warning: expecting prototype for inode.c(). Prototype was for ntfs_test_inode() instead
fs/ntfs/inode.c:2956: warning: expecting prototype for ntfs_write_inode(). Prototype was for __ntfs_write_inode() instead
fs/ntfs/mft.c:24: warning: expecting prototype for mft.c - NTFS kernel mft record operations. Part of the Linux(). Prototype was for MAX_BHS() instead
fs/ntfs/namei.c:263: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Inode operations for directories.
fs/ntfs/namei.c:368: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Export operations allowing NFS exporting of mounted NTFS partitions.
fs/ntfs/runlist.c:16: warning: Incorrect use of kernel-doc format: * ntfs_rl_mm - runlist memmove
fs/ntfs/runlist.c:22: warning: expecting prototype for runlist.c - NTFS runlist handling code. Part of the Linux(). Prototype was for ntfs_rl_mm() instead
fs/ntfs/super.c:61: warning: missing initial short description on line:
* simple_getbool -
fs/ntfs/super.c:2661: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* The complete super operations.
Link: https://lkml.kernel.org/r/20230109010041.21442-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix multiple kernel-doc warnings in freevxfs:
fs/freevxfs/vxfs_subr.c:45: warning: Function parameter or member 'mapping' not described in 'vxfs_get_page'
fs/freevxfs/vxfs_subr.c:45: warning: Excess function parameter 'ip' description in 'vxfs_get_page'
2 warnings
fs/freevxfs/vxfs_subr.c:101: warning: expecting prototype for vxfs_get_block(). Prototype was for vxfs_getblk() instead
fs/freevxfs/vxfs_super.c:184: warning: expecting prototype for vxfs_read_super(). Prototype was for vxfs_fill_super() instead
Link: https://lkml.kernel.org/r/20230109022915.17504-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The sort function has the inbuilt reversal option. We can use it to save
some time.
Link: https://lkml.kernel.org/r/20230106091319.3824-1-apantykhin@gmail.com
Signed-off-by: Alexander Pantyukhin <apantykhin@gmail.com>
Cc: Nikolay Borisov <nborisov@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This command provides a way to traverse the entire page hierarchy by a
given virtual address on x86. In addition to qemu's commands info
tlb/info mem it provides the complete information about the paging
structure for an arbitrary virtual address. It supports 4KB/2MB/1GB and 5
level paging.
Here is an example output for 2MB success translation:
(gdb) translate-vm address
cr3:
cr3 binary data 0x1085be003
next entry physical address 0x1085be000
---
bit 3 page level write through False
bit 4 page level cache disabled False
level 4:
entry address 0xffff8881085be7f8
page entry binary data 0x800000010ac83067
next entry physical address 0x10ac83000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable True
level 3:
entry address 0xffff88810ac83a48
page entry binary data 0x101af7067
next entry physical address 0x101af7000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size False
bit 11 restart to ordinary False
bit 63 execute disable False
level 2:
entry address 0xffff888101af7368
page entry binary data 0x80000001634008e7
page size 2MB
page physical address 0x163400000
---
bit 0 entry present True
bit 1 read/write access allowed True
bit 2 user access allowed True
bit 3 page level write through False
bit 4 page level cache disabled False
bit 5 entry has been accessed True
bit 7 page size True
bit 6 page dirty True
bit 8 global translation False
bit 11 restart to ordinary True
bit 12 pat False
bits (59, 62) protection key 0
bit 63 execute disable True
[dmitrii.bundin.a@gmail.com: add SPDX line, other tweaks]
Link: https://lkml.kernel.org/r/20230113175151.22278-1-dmitrii.bundin.a@gmail.com
[akpm@linux-foundation.org: s/physicall/physical/]
Link: https://lkml.kernel.org/r/20230102171014.31408-1-dmitrii.bundin.a@gmail.com
Signed-off-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Acked by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When destroying a kthread worker warn if there are still some pending
delayed works. This indicates that the caller should clear all pending
delayed works before destroying the kthread worker.
Link: https://lkml.kernel.org/r/20230104144230.938521-1-qiang1.zhang@intel.com
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
/proc/cmdline is never removed, mark is as permanent for slightly faster
open and close.
Link: https://lkml.kernel.org/r/Y66xAveh2yUsP7m9@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It was suggested by Fabio that kunmap() be marked deprecated in
checkpatch.[1] This did not seem necessary until an invalid conversion of
kmap_local_page() appeared in mainline.[2][3] The introduction of this bug
would have been flagged with kunmap() being marked deprecated.
Add kunmap() and kunmap_atomic() to checkpatch to help prevent further
confusion.
[1] https://lore.kernel.org/all/1884934.6tgchFWduM@suse/
[2] d406d26745 ("cifs: skip alloc when request has no pages")
[3] https://lore.kernel.org/r/20221229-cifs-kmap-v1-1-c70d0e9a53eb@intel.com
Link: https://lkml.kernel.org/r/20221229-kmap-checkpatch-v2-1-919fc4d4e3c2@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "spelling: Fix some trivial typos".
Seems like permitted has two t's :), Lets add that to spellings to help
others.
This patch (of 3):
Add another common typo. Noticed when I sent a patch with the typo and
in kvm and of.
[ribalda@chromium.org: fix trivial typo]
Link: https://lkml.kernel.org/r/20221220-permited-v1-2-52ea9857fa61@chromium.org
Link: https://lkml.kernel.org/r/20221220-permited-v1-1-52ea9857fa61@chromium.org
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Variables are assigned first and then used. Initialization is not
required.
[akpm@linux-foundation.org: give hfsplus_listxattr:key_len narrower scope]
Link: https://lkml.kernel.org/r/20221221032119.10037-1-xupengfei@nfschina.com
Signed-off-by: XU pengfei <xupengfei@nfschina.com>
Reviewed-by: Andrew Morton <akpm@linux-foudation.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When working on SoC bring-up, (a full) userspace may not be available,
making it hard to benchmark the CPU performance of the system under
development. Still, one may want to have a rough idea of the (relative)
performance of one or more CPU cores, especially when working on e.g. the
clock driver that controls the CPU core clock(s).
Hence make the classical Dhrystone 2.1 benchmark available as a Linux
kernel test module, based on[1].
When built-in, this benchmark can be run without any userspace present.
Parallel runs (run on multiple CPU cores) are supported, just kick the
"run" file multiple times.
Note that the actual figures depend on the configuration options that
control compiler optimization (e.g. CONFIG_CC_OPTIMIZE_FOR_SIZE vs.
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE), and on the compiler options used when
building the kernel in general. Hence numbers may differ from those
obtained by running similar benchmarks in userspace.
[1] https://github.com/qris/dhrystone-deb.git
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/4d07ad990740a5f1e426ce4566fb514f60ec9bdd.1670509558.git.geert+renesas@glider.be
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
[geert+renesas@glider.be: fix uninitialized use of ret]
Link: https://lkml.kernel.org/r/alpine.DEB.2.22.394.2212190857310.137329@ramsan.of.borg
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The percpu interface is supposed to be preempt and irq safe.
But:
The uniprocessor implementation of percpu_counter_add() is not irq safe:
if an interrupt happens during the +=, then the result is undefined.
Therefore: switch from preempt_disable() to local_irq_save().
This prevents interrupts from interrupting the +=, and as a side effect
prevents preemption.
Link: https://lkml.kernel.org/r/20221216150441.200533-2-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: "Sun, Jiebin" <jiebin.sun@intel.com>
Cc: <1vier1@web.de>
Cc: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "various irq handling fixes/docu updates".
If an interrupt happens between __this_cpu_read(*fbc->counters) and
this_cpu_add(*fbc->counters, amount), and that interrupt modifies the
per_cpu_counter, then the this_cpu_add() after the interrupt returns may
under/overflow.
Link: https://lkml.kernel.org/r/20221216150155.200389-1-manfred@colorfullife.com
Link: https://lkml.kernel.org/r/20221216150441.200533-1-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: "Sun, Jiebin" <jiebin.sun@intel.com>
Cc: <1vier1@web.de>
Cc: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add a section about the requirements of the error injectable functions and
the type of errors.
Since this section must be read before using ALLOW_ERROR_INJECTION()
macro, that section is referred from the comment of the macro too.
Link: https://lkml.kernel.org/r/167081321427.387937.15475445689482551048.stgit@devnote3
Link: https://lore.kernel.org/all/20221211115218.2e6e289bb85f8cf53c11aa97@kernel.org/T/#u
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Chris Mason <clm@meta.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Florent Revest <revest@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "error-injection: Clarify the requirements of error
injectable functions".
Patches for clarifying the requirement of error injectable functions and
to remove the confusing EI_ETYPE_NONE.
This patch (of 2):
Since the EI_ETYPE_NONE is confusing type, replace it with appropriate
errno. The EI_ETYPE_NONE has been introduced for a dummy (error) value,
but it can mislead people that they can use ALLOW_ERROR_INJECTION(func,
NONE). So remove it from the EI_ETYPE and use appropriate errno instead.
[akpm@linux-foundation.org: include/linux/error-injection.h needs errno.h]
Link: https://lkml.kernel.org/r/167081319306.387937.10079195394503045678.stgit@devnote3
Link: https://lkml.kernel.org/r/167081320421.387937.4259807348852421112.stgit@devnote3
Fixes: 663faf9f7b ("error-injection: Add injectable error types")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Chris Mason <clm@meta.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Florent Revest <revest@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
generic_ptr is a void * type and does not require a cast.
Link: https://lkml.kernel.org/r/20221213073633.3586-1-zeming@nfschina.com
Signed-off-by: Li zeming <zeming@nfschina.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The void * type pointer does not need to be cast and assigned to another
pointer.
Link: https://lkml.kernel.org/r/20221213074522.3738-1-zeming@nfschina.com
Signed-off-by: Li zeming <zeming@nfschina.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tom Rix