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2022-09-12udf: Support splicing to fileJan Kara1-0/+1
Add explicit support for splicing from pipe to file through iter_file_splice_write(). Commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") removed the default .splice_write operation which effectively removed UDF support for splicing from pipe. Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Reported-by: kernel test robot <yujie.liu@intel.com> Link: https://lore.kernel.org/r/202209081443.593ab12-yujie.liu@intel.com Signed-off-by: Jan Kara <jack@suse.cz>
2022-09-12arm64: defconfig: enable ARCH_NXPMichael Walle1-0/+1
Commit 566e373fe047 ("arm64: Kconfig.platforms: Group NXP platforms together") introduced a new symbol ARCH_NXP and made ARCH_LAYERSCAPE (among others) depend on it, but didn't enable it in the defconfig. Thus, now the defconfig doesn't include support for any NXP architectures anymore. Fix it. Fixes: 566e373fe047 ("arm64: Kconfig.platforms: Group NXP platforms together") Signed-off-by: Michael Walle <michael@walle.cc> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2022-09-12arm64: dts: imx8mp-tqma8mpql-mba8mpxl: add missing pinctrl for RTC alarmAlexander Stein1-0/+6
Although the RTC is on the module, the RTC_EVENT# signal is connected on the mainboard. Already set by bootloader, but make it explicit in Linux as well. Fixes: 418d1d840e42 ("arm64: dts: freescale: add initial device tree for TQMa8MPQL with i.MX8MP") Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2022-09-12ASoC: rt5640: Fix the issue of the abnormal JD2 statusOder Chiou2-19/+59
The patch fixes the issue of the abnormal JD2 status. Signed-off-by: Oder Chiou <oder_chiou@realtek.com> Reported-by: Sameer Pujar <spujar@nvidia.com> Link: https://lore.kernel.org/r/20220912072931.1856-1-oder_chiou@realtek.com Signed-off-by: Mark Brown <broonie@kernel.org>
2022-09-12ARM: dts: imx: update sdma node name formatJoy Zou11-11/+11
Node names should be generic, so change the sdma node name format 'sdma' into 'dma-controller'. Acked-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Joy Zou <joy.zou@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2022-09-12Merge tag 'amd-drm-next-6.1-2022-09-08' of https://gitlab.freedesktop.org/agd5f/linux into drm-nextDave Airlie181-3687/+69774
amd-drm-next-6.1-2022-09-08: amdgpu: - Mode2 reset for RDNA2 - Lots of new DC documentation - Add documentation about different asic families - DSC improvements - Aldebaran fixes - Misc spelling and grammar fixes - GFXOFF stats support for vangogh - DC frame size fixes - NBIO 7.7 updates - DCN 3.2 updates - DCN 3.1.4 Updates - SMU 13.x updates - Misc bug fixes - Rework DC register offset handling - GC 11.x updates - PSP 13.x updates - SDMA 6.x updates - GMC 11.x updates - SR-IOV updates - PSP fixes for TA unloading - DSC passthrough support - Misc code cleanups amdkfd: - ISA fixes for some GC 10.3 IPs - Misc code cleanups radeon: - Delayed work flush fix - Use time_after for some jiffies calculations drm: - DSC passthrough aux support Signed-off-by: Dave Airlie <airlied@redhat.com> From: Alex Deucher <alexander.deucher@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220908155202.57862-1-alexander.deucher@amd.com
2022-09-12Merge drm/drm-next into drm-intel-nextJani Nikula545-17415/+22002
Backmerge to sync the DP MST atomic changes to drm-intel-next. Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2022-09-12ALSA: dummy: Add customizable volume min/max.YJ Lee1-10/+24
Add module parameters to support customized min/max volume leveling, which will be useful to test devices with different volume granularity. Signed-off-by: YJ Lee <yunjunlee@chromium.org> Link: https://lore.kernel.org/r/20220912072945.760949-1-yunjunlee@chromium.org Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-09-12block/drbd: remove unused w_start_resync declarationGaosheng Cui1-1/+0
w_start_resync has been removed since commit ac0acb9e39ac ("drbd: use drbd_device_post_work() in more places"), so remove it. Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12ALSA: dummy: Fix trailing whitespaces.YJ Lee1-4/+4
Fix checkpatch.pl ERROR: trailing whitespaces. Signed-off-by: YJ Lee <yunjunlee@chromium.org> Link: https://lore.kernel.org/r/20220912072854.760824-1-yunjunlee@chromium.org Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-09-12drm/aperture: Fix some kerneldoc commentsThierry Reding1-5/+5
Reword some kerneldoc comments for the DRM aperture handling code. Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20220905162241.391226-1-thierry.reding@gmail.com
2022-09-12drm/format-helper: Add drm_fb_build_fourcc_list() helperThomas Zimmermann3-43/+123
Add drm_fb_build_fourcc_list() function that builds a list of supported formats from native and emulated ones. Helpful for all drivers that do format conversion as part of their plane updates. Update current caller. v3: * improve warnings on ignored formats (Sam) v2: * use u32 instead of uint32_t (Sam) * print a warning if output array is too small (Sam) * comment fixes (Sam) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-5-tzimmermann@suse.de
2022-09-12drm/modes: Add initializer macro DRM_MODE_INIT()Thomas Zimmermann2-19/+39
The macro DRM_MODE_INIT() initializes an instance of struct drm_display_mode with typical parameters. Convert simpledrm and also update the macro DRM_SIMPLE_MODE(). v3: * fix DRM_MODE_INIT() docs (kernel test robot) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-4-tzimmermann@suse.de
2022-09-12drm/probe-helper: Add drm_crtc_helper_mode_valid_fixed()Thomas Zimmermann14-11/+69
Add drm_crtc_helper_mode_valid_fixed(), which validates a given mode against a display hardware's mode. Convert simpledrm and use it in a few other drivers with static modes. v4: * remove empty line after opening brace v2: * rename 'static' and 'hw' to 'fixed' everywhere Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-3-tzimmermann@suse.de
2022-09-12drm/probe-helper: Add drm_connector_helper_get_modes_fixed()Thomas Zimmermann5-51/+46
Add drm_connector_helper_get_modes_fixed(), which duplicates a single display mode for a connector. Convert drivers. v2: * rename 'static' and 'hw' to 'fixed' everywhere * fix typo 'there' to 'their' (Sam) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20220905141648.22013-2-tzimmermann@suse.de
2022-09-12blk-throttle: cleanup tg_update_disptime()Yu Kuai1-4/+7
tg_update_disptime() only need to adjust postion for 'tg' in 'parent_sq', there is no need to call throtl_enqueue/dequeue_tg(), since they will set/clear flag THROTL_TG_PENDING and increase/decrease nr_pending, which is useless. By the way, clear the flag/decrease nr_pending while there are still throttled bios is not good for debugging. There are no functional changes. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: calling throtl_dequeue/enqueue_tg in pairsYu Kuai1-2/+2
It's a little weird to call throtl_dequeue_tg() unconditionally in throtl_select_dispatch(), since it will be called in tg_update_disptime() again if some bio is still throttled. Thus call it later if there are no throttled bio. There are no functional changes. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: use 'READ/WRITE' instead of '0/1'Yu Kuai1-3/+3
Make the code easier to read, like everywhere else. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220827101637.1775111-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: fix io hung due to configuration updatesYu Kuai2-6/+61
If new configuration is submitted while a bio is throttled, then new waiting time is recalculated regardless that the bio might already wait for some time: tg_conf_updated throtl_start_new_slice tg_update_disptime throtl_schedule_next_dispatch Then io hung can be triggered by always submmiting new configuration before the throttled bio is dispatched. Fix the problem by respecting the time that throttled bio already waited. In order to do that, add new fields to record how many bytes/io are waited, and use it to calculate wait time for throttled bio under new configuration. Some simple test: 1) cd /sys/fs/cgroup/blkio/ echo $$ > cgroup.procs echo "8:0 2048" > blkio.throttle.write_bps_device { sleep 2 echo "8:0 1024" > blkio.throttle.write_bps_device } & dd if=/dev/zero of=/dev/sda bs=8k count=1 oflag=direct 2) cd /sys/fs/cgroup/blkio/ echo $$ > cgroup.procs echo "8:0 1024" > blkio.throttle.write_bps_device { sleep 4 echo "8:0 2048" > blkio.throttle.write_bps_device } & dd if=/dev/zero of=/dev/sda bs=8k count=1 oflag=direct test results: io finish time before this patch with this patch 1) 10s 6s 2) 8s 6s Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-5-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: factor out code to calculate ios/bytes_allowedYu Kuai1-24/+35
No functional changes, new apis will be used in later patches to calculate wait time for throttled bios when new configuration is submitted. Noted this patch also rename tg_with_in_iops/bps_limit() to tg_within_iops/bps_limit(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: prevent overflow while calculating wait timeYu Kuai1-5/+3
There is a problem found by code review in tg_with_in_bps_limit() that 'bps_limit * jiffy_elapsed_rnd' might overflow. Fix the problem by calling mul_u64_u64_div_u64() instead. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-3-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12blk-throttle: fix that io throttle can only work for single bioYu Kuai5-19/+9
Test scripts: cd /sys/fs/cgroup/blkio/ echo "8:0 1024" > blkio.throttle.write_bps_device echo $$ > cgroup.procs dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct & dd if=/dev/zero of=/dev/sda bs=10k count=1 oflag=direct & Test result: 10240 bytes (10 kB, 10 KiB) copied, 10.0134 s, 1.0 kB/s 10240 bytes (10 kB, 10 KiB) copied, 10.0135 s, 1.0 kB/s The problem is that the second bio is finished after 10s instead of 20s. Root cause: 1) second bio will be flagged: __blk_throtl_bio while (true) { ... if (sq->nr_queued[rw]) -> some bio is throttled already break }; bio_set_flag(bio, BIO_THROTTLED); -> flag the bio 2) flagged bio will be dispatched without waiting: throtl_dispatch_tg tg_may_dispatch tg_with_in_bps_limit if (bps_limit == U64_MAX || bio_flagged(bio, BIO_THROTTLED)) *wait = 0; -> wait time is zero return true; commit 9f5ede3c01f9 ("block: throttle split bio in case of iops limit") support to count split bios for iops limit, thus it adds flagged bio checking in tg_with_in_bps_limit() so that split bios will only count once for bps limit, however, it introduce a new problem that io throttle won't work if multiple bios are throttled. In order to fix the problem, handle iops/bps limit in different ways: 1) for iops limit, there is no flag to record if the bio is throttled, and iops is always applied. 2) for bps limit, original bio will be flagged with BIO_BPS_THROTTLED, and io throttle will ignore bio with the flag. Noted this patch also remove the code to set flag in __bio_clone(), it's introduced in commit 111be8839817 ("block-throttle: avoid double charge"), and author thinks split bio can be resubmited and throttled again, which is wrong because split bio will continue to dispatch from caller. Fixes: 9f5ede3c01f9 ("block: throttle split bio in case of iops limit") Cc: <stable@vger.kernel.org> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220829022240.3348319-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-12sbitmap: fix batched wait_cnt accountingKeith Busch3-16/+26
Batched completions can clear multiple bits, but we're only decrementing the wait_cnt by one each time. This can cause waiters to never be woken, stalling IO. Use the batched count instead. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215679 Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20220909184022.1709476-1-kbusch@fb.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-11latencytop: use the last element of latency_record of systemwuchi1-2/+2
In account_global_scheduler_latency(), when we don't find the matching latency_record we try to select one which is unused in latency_record[MAXLR], but the condition will skip the last one. if (i >= MAXLR-1) Fix that. Link: https://lkml.kernel.org/r/20220903135233.5225-1-wuchi.zero@gmail.com Signed-off-by: wuchi <wuchi.zero@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foudation.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11kernel/utsname_sysctl.c: print kernel archPetr Vorel2-0/+12
Print the machine hardware name (UTS_MACHINE) in /proc/sys/kernel/arch. This helps people who debug kernel with initramfs with minimal environment (i.e. without coreutils or even busybox) or allow to open sysfs file instead of run 'uname -m' in high level languages. Link: https://lkml.kernel.org/r/20220901194403.3819-1-pvorel@suse.cz Signed-off-by: Petr Vorel <pvorel@suse.cz> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Sterba <dsterba@suse.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11checkpatch: handle FILE pointer typeMickaël Salaün1-1/+5
When using a "FILE *" type, checkpatch considers this an error: ERROR: need consistent spacing around '*' (ctx:WxV) #32: FILE: f.c:8: +static void a(FILE *const b) ^ Fix this by explicitly defining "FILE" as a common type. This is useful for user space patches. With this patch, we now get: <E> <E> <_>WS( ) <E> <E> <_>IDENT(static) <E> <V> <_>WS( ) <E> <V> <_>DECLARE(void ) <E> <T> <_>FUNC(a) <E> <V> <V>PAREN('(') <EV> <N> <_>DECLARE(FILE *const ) <EV> <T> <_>IDENT(b) <EV> <V> <_>PAREN(')') -> V <E> <V> <_>WS( ) 32 > . static void a(FILE *const b) 32 > EEVVVVVVVTTTTTVNTTTTTTTTTTTTVVV 32 > ______________________________ Link: https://lkml.kernel.org/r/20220902111923.1488671-1-mic@digikod.net Link: https://lore.kernel.org/r/20220902111923.1488671-1-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net> Acked-by: Joe Perches <joe@perches.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11asm-generic: make parameter types consistent in _unaligned_be48()Andy Shevchenko1-1/+1
There is a convention to use internal kernel types, so replace __u8 by u8. Link: https://lkml.kernel.org/r/20220830172713.43686-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11kernel/profile.c: simplify duplicated code in profile_setup()wuchi1-18/+14
The code to parse option string "schedule/sleep/kvm" of cmdline in function profile_setup is redundant, so simplify that. Link: https://lkml.kernel.org/r/20220901003121.53597-1-wuchi.zero@gmail.com Signed-off-by: wuchi <wuchi.zero@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foudation.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11ntfs: check overflow when iterating ATTR_RECORDsHawkins Jiawei1-0/+8
Kernel iterates over ATTR_RECORDs in mft record in ntfs_attr_find(). Because the ATTR_RECORDs are next to each other, kernel can get the next ATTR_RECORD from end address of current ATTR_RECORD, through current ATTR_RECORD length field. The problem is that during iteration, when kernel calculates the end address of current ATTR_RECORD, kernel may trigger an integer overflow bug in executing `a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))`. This may wrap, leading to a forever iteration on 32bit systems. This patch solves it by adding some checks on calculating end address of current ATTR_RECORD during iteration. Link: https://lkml.kernel.org/r/20220831160935.3409-4-yin31149@gmail.com Link: https://lore.kernel.org/all/20220827105842.GM2030@kadam/ Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> Suggested-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: chenxiaosong (A) <chenxiaosong2@huawei.com> Cc: syzkaller-bugs <syzkaller-bugs@googlegroups.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11ntfs: fix out-of-bounds read in ntfs_attr_find()Hawkins Jiawei1-4/+16
Kernel iterates over ATTR_RECORDs in mft record in ntfs_attr_find(). To ensure access on these ATTR_RECORDs are within bounds, kernel will do some checking during iteration. The problem is that during checking whether ATTR_RECORD's name is within bounds, kernel will dereferences the ATTR_RECORD name_offset field, before checking this ATTR_RECORD strcture is within bounds. This problem may result out-of-bounds read in ntfs_attr_find(), reported by Syzkaller: ================================================================== BUG: KASAN: use-after-free in ntfs_attr_find+0xc02/0xce0 fs/ntfs/attrib.c:597 Read of size 2 at addr ffff88807e352009 by task syz-executor153/3607 [...] Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 ntfs_attr_find+0xc02/0xce0 fs/ntfs/attrib.c:597 ntfs_attr_lookup+0x1056/0x2070 fs/ntfs/attrib.c:1193 ntfs_read_inode_mount+0x89a/0x2580 fs/ntfs/inode.c:1845 ntfs_fill_super+0x1799/0x9320 fs/ntfs/super.c:2854 mount_bdev+0x34d/0x410 fs/super.c:1400 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] </TASK> The buggy address belongs to the physical page: page:ffffea0001f8d400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e350 head:ffffea0001f8d400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011842140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807e351f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e351f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e352000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e352080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e352100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== This patch solves it by moving the ATTR_RECORD strcture's bounds checking earlier, then checking whether ATTR_RECORD's name is within bounds. What's more, this patch also add some comments to improve its maintainability. Link: https://lkml.kernel.org/r/20220831160935.3409-3-yin31149@gmail.com Link: https://lore.kernel.org/all/1636796c-c85e-7f47-e96f-e074fee3c7d3@huawei.com/ Link: https://groups.google.com/g/syzkaller-bugs/c/t_XdeKPGTR4/m/LECAuIGcBgAJ Signed-off-by: chenxiaosong (A) <chenxiaosong2@huawei.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> Reported-by: syzbot+5f8dcabe4a3b2c51c607@syzkaller.appspotmail.com Tested-by: syzbot+5f8dcabe4a3b2c51c607@syzkaller.appspotmail.com Cc: Anton Altaparmakov <anton@tuxera.com> Cc: syzkaller-bugs <syzkaller-bugs@googlegroups.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11ntfs: fix use-after-free in ntfs_attr_find()Hawkins Jiawei1-0/+7
Patch series "ntfs: fix bugs about Attribute", v2. This patchset fixes three bugs relative to Attribute in record: Patch 1 adds a sanity check to ensure that, attrs_offset field in first mft record loading from disk is within bounds. Patch 2 moves the ATTR_RECORD's bounds checking earlier, to avoid dereferencing ATTR_RECORD before checking this ATTR_RECORD is within bounds. Patch 3 adds an overflow checking to avoid possible forever loop in ntfs_attr_find(). Without patch 1 and patch 2, the kernel triggersa KASAN use-after-free detection as reported by Syzkaller. Although one of patch 1 or patch 2 can fix this, we still need both of them. Because patch 1 fixes the root cause, and patch 2 not only fixes the direct cause, but also fixes the potential out-of-bounds bug. This patch (of 3): Syzkaller reported use-after-free read as follows: ================================================================== BUG: KASAN: use-after-free in ntfs_attr_find+0xc02/0xce0 fs/ntfs/attrib.c:597 Read of size 2 at addr ffff88807e352009 by task syz-executor153/3607 [...] Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 ntfs_attr_find+0xc02/0xce0 fs/ntfs/attrib.c:597 ntfs_attr_lookup+0x1056/0x2070 fs/ntfs/attrib.c:1193 ntfs_read_inode_mount+0x89a/0x2580 fs/ntfs/inode.c:1845 ntfs_fill_super+0x1799/0x9320 fs/ntfs/super.c:2854 mount_bdev+0x34d/0x410 fs/super.c:1400 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] </TASK> The buggy address belongs to the physical page: page:ffffea0001f8d400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e350 head:ffffea0001f8d400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011842140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88807e351f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e351f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e352000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e352080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e352100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Kernel will loads $MFT/$DATA's first mft record in ntfs_read_inode_mount(). Yet the problem is that after loading, kernel doesn't check whether attrs_offset field is a valid value. To be more specific, if attrs_offset field is larger than bytes_allocated field, then it may trigger the out-of-bounds read bug(reported as use-after-free bug) in ntfs_attr_find(), when kernel tries to access the corresponding mft record's attribute. This patch solves it by adding the sanity check between attrs_offset field and bytes_allocated field, after loading the first mft record. Link: https://lkml.kernel.org/r/20220831160935.3409-1-yin31149@gmail.com Link: https://lkml.kernel.org/r/20220831160935.3409-2-yin31149@gmail.com Signed-off-by: Hawkins Jiawei <yin31149@gmail.com> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: ChenXiaoSong <chenxiaosong2@huawei.com> Cc: syzkaller-bugs <syzkaller-bugs@googlegroups.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11initramfs: mark my_inptr as __initdatawuchi1-1/+1
As my_inptr is only used in __init function unpack_to_rootfs(), mark it as __initdata to allow it be freed after boot. Link: https://lkml.kernel.org/r/20220827071116.83078-1-wuchi.zero@gmail.com Signed-off-by: wuchi <wuchi.zero@gmail.com> Reviewed-by: David Disseldorp <ddiss@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Martin Wilck <mwilck@suse.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11fail_function: fix wrong use of fei_attr_remove()Yang Yingliang1-1/+1
If register_kprobe() fails, the new attr is not added to the list yet, so it should call fei_attr_free() intstead. Link: https://lkml.kernel.org/r/20220826073337.2085798-3-yangyingliang@huawei.com Fixes: 4b1a29a7f542 ("error-injection: Support fault injection framework") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11fail_function: refactor code of checking return value of register_kprobe()Yang Yingliang1-6/+5
Refactor the error handling of register_kprobe() to improve readability. No functional change. Link: https://lkml.kernel.org/r/20220826073337.2085798-2-yangyingliang@huawei.com Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11fail_function: switch to memdup_user_nul() helperYang Yingliang1-9/+4
Use memdup_user_nul() helper instead of open-coding to simplify the code. Link: https://lkml.kernel.org/r/20220826073337.2085798-1-yangyingliang@huawei.com Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11smpboot: use atomic_try_cmpxchg in cpu_wait_death and cpu_report_deathUros Bizjak1-7/+8
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old in cpu_wait_death and cpu_report_death. 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, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. No functional change intended. Link: https://lkml.kernel.org/r/20220825145603.5811-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11task_work: use try_cmpxchg in task_work_add, task_work_cancel_match and task_work_runUros Bizjak1-7/+9
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in task_work_add, task_work_cancel_match and task_work_run. 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, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. The patch avoids extra memory read in case cmpxchg fails. Link: https://lkml.kernel.org/r/20220823152632.4517-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11lib: move from strlcpy with unused retval to strscpyWolfram Sang1-1/+1
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818210203.8251-1-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11init: move from strlcpy with unused retval to strscpyWolfram Sang2-4/+4
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818210200.8203-1-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11reiserfs: move from strlcpy with unused retval to strscpyWolfram Sang1-2/+2
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818210153.8095-1-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11ocfs2: move from strlcpy with unused retval to strscpyWolfram Sang2-3/+3
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818210123.7637-4-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11ia64: move from strlcpy with unused retval to strscpyWolfram Sang1-1/+1
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818205940.6216-1-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11alpha: move from strlcpy with unused retval to strscpyWolfram Sang1-2/+2
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220818205936.6144-1-wsa+renesas@sang-engineering.com Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.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>
2022-09-11bitops: use try_cmpxchg in set_mask_bits and bit_clear_unlessUros Bizjak1-5/+6
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in set_mask_bits and bit_clear_unless. 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, enabling further code simplifications. Link: https://lkml.kernel.org/r/20220822143851.3290-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11hfs: replace kmap() with kmap_local_page() in btree.cFabio M. De Francesco1-14/+16
kmap() is being deprecated in favor of kmap_local_page(). Two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap's pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and still valid. Since its use in btree.c is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in btree.c. Where possible, use the suited standard helpers (memzero_page(), memcpy_page()) instead of open coding kmap_local_page() plus memset() or memcpy(). Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Link: https://lkml.kernel.org/r/20220821180400.8198-4-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Chaitanya Kulkarni <kch@nvidia.com> Cc: Christian Brauner (Microsoft) <brauner@kernel.org> Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kees Cook <keescook@chromium.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11hfs: replace kmap() with kmap_local_page() in bnode.cFabio M. De Francesco1-20/+12
kmap() is being deprecated in favor of kmap_local_page(). Two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap's pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and still valid. Since its use in bnode.c is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in bnode.c. Where possible, use the suited standard helpers (memzero_page(), memcpy_page()) instead of open coding kmap_local_page() plus memset() or memcpy(). Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Link: https://lkml.kernel.org/r/20220821180400.8198-3-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Chaitanya Kulkarni <kch@nvidia.com> Cc: Christian Brauner (Microsoft) <brauner@kernel.org> Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kees Cook <keescook@chromium.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11hfs: unmap the page in the "fail_page" labelFabio M. De Francesco1-0/+1
Patch series "hfs: Replace kmap() with kmap_local_page()". kmap() is being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmaps pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and still valid. Since its use in fs/hfs is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in fs/hfs. Where possible, use the suited standard helpers (memzero_page(), memcpy_page()) instead of open coding kmap_local_page() plus memset() or memcpy(). Fix a bug due to a page being not unmapped if the code jumps to the "fail_page" label (1/3). Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. This patch (of 3): Several paths within hfs_btree_open() jump to the "fail_page" label where put_page() is called while the page is still mapped. Call kunmap() to unmap the page soon before put_page(). Link: https://lkml.kernel.org/r/20220821180400.8198-1-fmdefrancesco@gmail.com Link: https://lkml.kernel.org/r/20220821180400.8198-2-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Chaitanya Kulkarni <kch@nvidia.com> Cc: Christian Brauner (Microsoft) <brauner@kernel.org> Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com> Cc: Matthew Wilcox <willy@infradead.org>] Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kees Cook <keescook@chromium.org> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11kexec: replace kmap() with kmap_local_page()Fabio M. De Francesco1-4/+4
kmap() is being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap's pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and are still valid. Since its use in kexec_core.c is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in kexec_core.c. Tested on a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Link: https://lkml.kernel.org/r/20220821182519.9483-1-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11iversion: use atomic64_try_cmpxchg)Uros Bizjak1-23/+9
Use atomic64_try_cmpxchg instead of atomic64_cmpxchg (*ptr, old, new) == old in inode_set_max_iversion_raw, inode_maybe_inc_version and inode_query_iversion. 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, enabling further code simplifications. The loop in inode_maybe_inc_iversion improves from: 5563: 48 89 ca mov %rcx,%rdx 5566: 48 89 c8 mov %rcx,%rax 5569: 48 83 e2 fe and $0xfffffffffffffffe,%rdx 556d: 48 83 c2 02 add $0x2,%rdx 5571: f0 48 0f b1 16 lock cmpxchg %rdx,(%rsi) 5576: 48 39 c1 cmp %rax,%rcx 5579: 0f 84 85 fc ff ff je 5204 <...> 557f: 48 89 c1 mov %rax,%rcx 5582: eb df jmp 5563 <...> to: 5563: 48 89 c2 mov %rax,%rdx 5566: 48 83 e2 fe and $0xfffffffffffffffe,%rdx 556a: 48 83 c2 02 add $0x2,%rdx 556e: f0 48 0f b1 11 lock cmpxchg %rdx,(%rcx) 5573: 0f 84 8b fc ff ff je 5204 <...> 5579: eb e8 jmp 5563 <...> Link: https://lkml.kernel.org/r/20220821193011.88208-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11aio: use atomic_try_cmpxchg in __get_reqs_availableUros Bizjak1-6/+3
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old in __get_reqs_available. 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, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. No functional change intended. Link: https://lkml.kernel.org/r/20220714164851.3055-1-ubizjak@gmail.com Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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