kernel/git/stable/linux-stable.git/drivers/md/md.c, branch linux-6.5.y

md: don't rely on 'mddev->pers' to be set in mddev_suspend()

2023-11-28T17:14:44+00:00

[ Upstream commit b721e7885eb242aa2459ee66bb42ceef1bcf0f0c ] 'active_io' used to be initialized while the array is running, and 'mddev->pers' is set while the array is running as well. Hence caller must hold 'reconfig_mutex' and guarantee 'mddev->pers' is set before calling mddev_suspend(). Now that 'active_io' is initialized when mddev is allocated, such restriction doesn't exist anymore. In the meantime, follow up patches will refactor mddev_suspend(), hence add checking for 'mddev->pers' to prevent null-ptr-deref. Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230825030956.1527023-4-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin

md: Put the right device in md_seq_next

2023-09-23T09:14:34+00:00

commit c8870379a21fbd9ad14ca36204ccfbe9d25def43 upstream. If there are multiple arrays in system and one mddevice is marked with MD_DELETED and md_seq_next() is called in the middle of removal then it _get()s proper device but it may _put() deleted one. As a result, active counter may never be zeroed for mddevice and it cannot be removed. Put the device which has been _get with previous md_seq_next() call. Cc: stable@vger.kernel.org Fixes: 12a6caf27324 ("md: only delete entries from all_mddevs when the disk is freed") Reported-by: AceLan Kao Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217798 Cc: Yu Kuai Signed-off-by: Mariusz Tkaczyk Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230914152416.10819-1-mariusz.tkaczyk@linux.intel.com Signed-off-by: Greg Kroah-Hartman

md: fix warning for holder mismatch from export_rdev()

2023-09-23T09:14:32+00:00

[ Upstream commit 99892147f028d711f9d40fefad4f33632593864c ] Commit a1d767191096 ("md: use mddev->external to select holder in export_rdev()") fix the problem that 'claim_rdev' is used for blkdev_get_by_dev() while 'rdev' is used for blkdev_put(). However, if mddev->external is changed from 0 to 1, then 'rdev' is used for blkdev_get_by_dev() while 'claim_rdev' is used for blkdev_put(). And this problem can be reporduced reliably by following: New file: mdadm/tests/23rdev-lifetime devname=${dev0##*/} devt=`cat /sys/block/$devname/dev` pid="" runtime=2 clean_up_test() { pill -9 $pid echo clear > /sys/block/md0/md/array_state } trap 'clean_up_test' EXIT add_by_sysfs() { while true; do echo $devt > /sys/block/md0/md/new_dev done } remove_by_sysfs(){ while true; do echo remove > /sys/block/md0/md/dev-${devname}/state done } echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed" add_by_sysfs & pid="$pid $!" remove_by_sysfs & pid="$pid $!" sleep $runtime exit 0 Test cmd: ./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime Test result: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 960 at block/bdev.c:618 blkdev_put+0x27c/0x330 Modules linked in: multipath md_mod loop CPU: 0 PID: 960 Comm: test Not tainted 6.5.0-rc2-00121-g01e55c376936-dirty #50 RIP: 0010:blkdev_put+0x27c/0x330 Call Trace: export_rdev.isra.23+0x50/0xa0 [md_mod] mddev_unlock+0x19d/0x300 [md_mod] rdev_attr_store+0xec/0x190 [md_mod] sysfs_kf_write+0x52/0x70 kernfs_fop_write_iter+0x19a/0x2a0 vfs_write+0x3b5/0x770 ksys_write+0x74/0x150 __x64_sys_write+0x22/0x30 do_syscall_64+0x40/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix the problem by recording if 'rdev' is used as holder. Fixes: a1d767191096 ("md: use mddev->external to select holder in export_rdev()") Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230825025532.1523008-3-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin

md: don't dereference mddev after export_rdev()

2023-09-23T09:14:31+00:00

[ Upstream commit 7deac114be5fb25a4e865212ed0feaf5f85f2a28 ] Except for initial reference, mddev->kobject is referenced by rdev->kobject, and if the last rdev is freed, there is no guarantee that mddev is still valid. Hence mddev should not be used anymore after export_rdev(). This problem can be triggered by following test for mdadm at very low rate: New file: mdadm/tests/23rdev-lifetime devname=${dev0##*/} devt=`cat /sys/block/$devname/dev` pid="" runtime=2 clean_up_test() { pill -9 $pid echo clear > /sys/block/md0/md/array_state } trap 'clean_up_test' EXIT add_by_sysfs() { while true; do echo $devt > /sys/block/md0/md/new_dev done } remove_by_sysfs(){ while true; do echo remove > /sys/block/md0/md/dev-${devname}/state done } echo md0 > /sys/module/md_mod/parameters/new_array || die "create md0 failed" add_by_sysfs & pid="$pid $!" remove_by_sysfs & pid="$pid $!" sleep $runtime exit 0 Test cmd: ./test --save-logs --logdir=/tmp/ --keep-going --dev=loop --tests=23rdev-lifetime Test result: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bcb: 0000 [#4] PREEMPT SMP CPU: 0 PID: 1292 Comm: test Tainted: G D W 6.5.0-rc2-00121-g01e55c376936 #562 RIP: 0010:md_wakeup_thread+0x9e/0x320 [md_mod] Call Trace: mddev_unlock+0x1b6/0x310 [md_mod] rdev_attr_store+0xec/0x190 [md_mod] sysfs_kf_write+0x52/0x70 kernfs_fop_write_iter+0x19a/0x2a0 vfs_write+0x3b5/0x770 ksys_write+0x74/0x150 __x64_sys_write+0x22/0x30 do_syscall_64+0x40/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fix this problem by don't dereference mddev after export_rdev(). Fixes: 3ce94ce5d05a ("md: fix duplicate filename for rdev") Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230825025532.1523008-2-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin

md: restore 'noio_flag' for the last mddev_resume()

2023-09-13T07:53:20+00:00

[ Upstream commit e24ed04389f9619e0aaef615a8948633c182a8b0 ] memalloc_noio_save() is called for the first mddev_suspend(), and repeated mddev_suspend() only increase 'suspended'. However, memalloc_noio_restore() is also called for the first mddev_resume(), which means that memory reclaim will be enabled before the last mddev_resume() is called, while the array is still suspended. Fix this problem by restore 'noio_flag' for the last mddev_resume(). Fixes: 78f57ef9d50a ("md: use memalloc scope APIs in mddev_suspend()/mddev_resume()") Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20230628012931.88911-3-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Sasha Levin

dm raid: protect md_stop() with 'reconfig_mutex'

2023-07-25T15:55:50+00:00

__md_stop_writes() and __md_stop() will modify many fields that are protected by 'reconfig_mutex', and all the callers will grab 'reconfig_mutex' except for md_stop(). Also, update md_stop() to make certain 'reconfig_mutex' is held using lockdep_assert_held(). Fixes: 9d09e663d550 ("dm: raid456 basic support") Signed-off-by: Yu Kuai Signed-off-by: Mike Snitzer

md: fix 'delete_mutex' deadlock

2023-06-23T16:41:47+00:00

Commit 3ce94ce5d05a ("md: fix duplicate filename for rdev") introduce a new lock 'delete_mutex', and trigger a new deadlock: t1: remove rdev t2: sysfs writer rdev_attr_store rdev_attr_store mddev_lock state_store md_kick_rdev_from_array lock delete_mutex list_add mddev->deleting unlock delete_mutex mddev_unlock mddev_lock ... lock delete_mutex kobject_del // wait for sysfs writers to be done mddev_unlock lock delete_mutex // wait for delete_mutex, deadlock 'delete_mutex' is used to protect the list 'mddev->deleting', turns out that this list can be protected by 'reconfig_mutex' directly, and this lock can be removed. Fix this problem by removing the lock, and use 'reconfig_mutex' to protect the list. mddev_unlock() will move this list to a local list to be handled after 'reconfig_mutex' is dropped. Fixes: 3ce94ce5d05a ("md: fix duplicate filename for rdev") Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230621142933.1395629-1-yukuai1@huaweicloud.com

md: use mddev->external to select holder in export_rdev()

2023-06-23T16:39:00+00:00

mdadm test "10ddf-create-fail-rebuild" triggers warnings like the following [ 215.526357] ------------[ cut here ]------------ [ 215.527243] WARNING: CPU: 18 PID: 1264 at block/bdev.c:617 blkdev_put+0x269/0x350 [ 215.528334] Modules linked in: [ 215.528806] CPU: 18 PID: 1264 Comm: mdmon Not tainted 6.4.0-rc2+ #768 [ 215.529863] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS [ 215.531464] RIP: 0010:blkdev_put+0x269/0x350 [ 215.532167] Code: ff ff 49 8d 7d 10 e8 56 bf b8 ff 4d 8b 65 10 49 8d bc 24 58 05 00 00 e8 05 be b8 ff 41 83 ac 24 58 05 00 00 01 e9 44 ff ff ff <0f> 0b e9 52 fe ff ff 0f 0b e9 6b fe ff ff1 [ 215.534780] RSP: 0018:ffffc900040bfbf0 EFLAGS: 00010283 [ 215.535635] RAX: ffff888174001000 RBX: ffff88810b1c3b00 RCX: ffffffff819a4061 [ 215.536645] RDX: dffffc0000000000 RSI: dffffc0000000000 RDI: ffff88810b1c3ba0 [ 215.537657] RBP: ffff88810dbde800 R08: fffffbfff0fca983 R09: fffffbfff0fca983 [ 215.538674] R10: ffffc900040bfbf0 R11: fffffbfff0fca982 R12: ffff88810b1c3b38 [ 215.539687] R13: ffff88810b1c3b10 R14: ffff88810dbdecb8 R15: ffff88810b1c3b00 [ 215.540833] FS: 00007f2aabdff700(0000) GS:ffff888dfb400000(0000) knlGS:0000000000000000 [ 215.541961] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 215.542775] CR2: 00007fa19a85d934 CR3: 000000010c076006 CR4: 0000000000370ee0 [ 215.543814] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 215.544840] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 215.545885] Call Trace: [ 215.546257] [ 215.546608] export_rdev.isra.63+0x71/0xe0 [ 215.547338] mddev_unlock+0x1b1/0x2d0 [ 215.547898] array_state_store+0x28d/0x450 [ 215.548519] md_attr_store+0xd7/0x150 [ 215.549059] ? __pfx_sysfs_kf_write+0x10/0x10 [ 215.549702] kernfs_fop_write_iter+0x1b9/0x260 [ 215.550351] vfs_write+0x491/0x760 [ 215.550863] ? __pfx_vfs_write+0x10/0x10 [ 215.551445] ? __fget_files+0x156/0x230 [ 215.552053] ksys_write+0xc0/0x160 [ 215.552570] ? __pfx_ksys_write+0x10/0x10 [ 215.553141] ? ktime_get_coarse_real_ts64+0xec/0x100 [ 215.553878] do_syscall_64+0x3a/0x90 [ 215.554403] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 215.555125] RIP: 0033:0x7f2aade11847 [ 215.555696] Code: c3 66 90 41 54 49 89 d4 55 48 89 f5 53 89 fb 48 83 ec 10 e8 1b fd ff ff 4c 89 e2 48 89 ee 89 df 41 89 c0 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 48 89 448 [ 215.558398] RSP: 002b:00007f2aabdfeba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 [ 215.559516] RAX: ffffffffffffffda RBX: 0000000000000010 RCX: 00007f2aade11847 [ 215.560515] RDX: 0000000000000005 RSI: 0000000000438b8b RDI: 0000000000000010 [ 215.561512] RBP: 0000000000438b8b R08: 0000000000000000 R09: 00007f2aaecf0060 [ 215.562511] R10: 000000000e3ba40b R11: 0000000000000293 R12: 0000000000000005 [ 215.563647] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000c70750 [ 215.564693] [ 215.565029] irq event stamp: 15979 [ 215.565584] hardirqs last enabled at (15991): [] __up_console_sem+0x52/0x60 [ 215.566806] hardirqs last disabled at (16000): [] __up_console_sem+0x37/0x60 [ 215.568022] softirqs last enabled at (15716): [] __do_softirq+0x3eb/0x531 [ 215.569239] softirqs last disabled at (15711): [] irq_exit_rcu+0x115/0x160 [ 215.570434] ---[ end trace 0000000000000000 ]--- This means export_rdev() calls blkdev_put with a different holder than the one used by blkdev_get_by_dev(). This is because mddev->major_version == -2 is not a good check for external metadata. Fix this by using mddev->external instead. Also, do not clear mddev->external in md_clean(), as the flag might be used later in export_rdev(). Fixes: 2736e8eeb0cc ("block: use the holder as indication for exclusive opens") Cc: Christoph Hellwig Cc: Jens Axboe Signed-off-by: Song Liu Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230617052405.305871-1-song@kernel.org

md/md-bitmap: add a new helper to unplug bitmap asynchrously

2023-06-13T22:25:44+00:00

If bitmap is enabled, bitmap must update before submitting write io, this is why unplug callback must move these io to 'conf->pending_io_list' if 'current->bio_list' is not empty, which will suffer performance degradation. A new helper md_bitmap_unplug_async() is introduced to submit bitmap io in a kworker, so that submit bitmap io in raid10_unplug() doesn't require that 'current->bio_list' is empty. This patch prepare to limit the number of plugged bio. Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230529131106.2123367-6-yukuai1@huaweicloud.com

md/raid10: clean up md_add_new_disk()

2023-06-13T22:25:42+00:00

Commit 1a855a060665 ("md: fix bug with re-adding of partially recovered device.") only add device which is set to In_sync. But it let devices without metadata cannot be added when they should be. Commit bf572541ab44 ("md: fix regression with re-adding devices to arrays with no metadata") fix the above issue, it set device without metadata to In_sync when add new disk. However, after commit f466722ca614 ("md: Change handling of save_raid_disk and metadata update during recovery.") deletes changes of the first patch, setting In_sync for devcie without metadata is meanless because the flag will be cleared soon and will not be used during this period. Clean it up. Signed-off-by: Li Nan Reviewed-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230527101851.3266500-2-linan666@huaweicloud.com