kernel/linux.git/drivers/md/md-bitmap.c, branch v6.1.124

md: fix resync softlockup when bitmap size is less than array size

2024-06-12T09:03:06+00:00

[ Upstream commit f0e729af2eb6bee9eb58c4df1087f14ebaefe26b ] Is is reported that for dm-raid10, lvextend + lvchange --syncaction will trigger following softlockup: kernel:watchdog: BUG: soft lockup - CPU#3 stuck for 26s! [mdX_resync:6976] CPU: 7 PID: 3588 Comm: mdX_resync Kdump: loaded Not tainted 6.9.0-rc4-next-20240419 #1 RIP: 0010:_raw_spin_unlock_irq+0x13/0x30 Call Trace: md_bitmap_start_sync+0x6b/0xf0 raid10_sync_request+0x25c/0x1b40 [raid10] md_do_sync+0x64b/0x1020 md_thread+0xa7/0x170 kthread+0xcf/0x100 ret_from_fork+0x30/0x50 ret_from_fork_asm+0x1a/0x30 And the detailed process is as follows: md_do_sync j = mddev->resync_min while (j < max_sectors) sectors = raid10_sync_request(mddev, j, &skipped) if (!md_bitmap_start_sync(..., &sync_blocks)) // md_bitmap_start_sync set sync_blocks to 0 return sync_blocks + sectors_skippe; // sectors = 0; j += sectors; // j never change Root cause is that commit 301867b1c168 ("md/raid10: check slab-out-of-bounds in md_bitmap_get_counter") return early from md_bitmap_get_counter(), without setting returned blocks. Fix this problem by always set returned blocks from md_bitmap_get_counter"(), as it used to be. Noted that this patch just fix the softlockup problem in kernel, the case that bitmap size doesn't match array size still need to be fixed. Fixes: 301867b1c168 ("md/raid10: check slab-out-of-bounds in md_bitmap_get_counter") Reported-and-tested-by: Nigel Croxon Closes: https://lore.kernel.org/all/71ba5272-ab07-43ba-8232-d2da642acb4e@redhat.com/ Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20240422065824.2516-1-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Sasha Levin

md/md-bitmap: hold 'reconfig_mutex' in backlog_store()

2023-09-13T07:42:41+00:00

[ Upstream commit 44abfa6a95df425c0660d56043020b67e6d93ab8 ] Several reasons why 'reconfig_mutex' should be held: 1) rdev_for_each() is not safe to be called without the lock, because rdev can be removed concurrently. 2) mddev_destroy_serial_pool() and mddev_create_serial_pool() should not be called concurrently. 3) mddev_suspend() from mddev_destroy/create_serial_pool() should be protected by the lock. Fixes: 10c92fca636e ("md-bitmap: create and destroy wb_info_pool with the change of backlog") Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20230706083727.608914-3-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Sasha Levin

md/md-bitmap: remove unnecessary local variable in backlog_store()

2023-09-13T07:42:41+00:00

[ Upstream commit b4d129640f194ffc4cc64c3e97f98ae944c072e8 ] Local variable is definied first in the beginning of backlog_store(), there is no need to define it again. Fixes: 8c13ab115b57 ("md/bitmap: don't set max_write_behind if there is no write mostly device") Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20230706083727.608914-2-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Sasha Levin

md/raid1-10: submit write io directly if bitmap is not enabled

2023-07-19T14:20:58+00:00

[ Upstream commit 7db922bae3abdf0a1db81ef7228cc0b996a0c1e3 ] Commit 6cce3b23f6f8 ("[PATCH] md: write intent bitmap support for raid10") add bitmap support, and it changed that write io is submitted through daemon thread because bitmap need to be updated before write io. And later, plug is used to fix performance regression because all the write io will go to demon thread, which means io can't be issued concurrently. However, if bitmap is not enabled, the write io should not go to daemon thread in the first place, and plug is not needed as well. Fixes: 6cce3b23f6f8 ("[PATCH] md: write intent bitmap support for raid10") Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230529131106.2123367-5-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin

md/raid10: check slab-out-of-bounds in md_bitmap_get_counter

2023-07-19T14:20:57+00:00

[ Upstream commit 301867b1c16805aebbc306aafa6ecdc68b73c7e5 ] If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage() will return -EINVAL because 'page >= bitmap->pages', but the return value was not checked immediately in md_bitmap_get_counter() in order to set *blocks value and slab-out-of-bounds occurs. Move check of 'page >= bitmap->pages' to md_bitmap_get_counter() and return directly if true. Fixes: ef4256733506 ("md/bitmap: optimise scanning of empty bitmaps.") Signed-off-by: Li Nan Reviewed-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230515134808.3936750-2-linan666@huaweicloud.com Signed-off-by: Sasha Levin

md/bitmap: Fix bitmap chunk size overflow issues

2023-01-07T10:11:51+00:00

commit 4555211190798b6b6fa2c37667d175bf67945c78 upstream. - limit bitmap chunk size internal u64 variable to values not overflowing the u32 bitmap superblock structure variable stored on persistent media - assign bitmap chunk size internal u64 variable from unsigned values to avoid possible sign extension artifacts when assigning from a s32 value The bug has been there since at least kernel 4.0. Steps to reproduce it: 1: mdadm -C /dev/mdx -l 1 --bitmap=internal --bitmap-chunk=256M -e 1.2 -n2 /dev/rnbd1 /dev/rnbd2 2 resize member device rnbd1 and rnbd2 to 8 TB 3 mdadm --grow /dev/mdx --size=max The bitmap_chunksize will overflow without patch. Cc: stable@vger.kernel.org Signed-off-by: Florian-Ewald Mueller Signed-off-by: Jack Wang Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

drivers/md/md-bitmap: check the return value of md_bitmap_get_counter()

2022-12-31T12:33:01+00:00

[ Upstream commit 3bd548e5b819b8c0f2c9085de775c5c7bff9052f ] Check the return value of md_bitmap_get_counter() in case it returns NULL pointer, which will result in a null pointer dereference. v2: update the check to include other dereference Signed-off-by: Li Zhong Signed-off-by: Song Liu Signed-off-by: Sasha Levin

fs/buffer: Combine two submit_bh() and ll_rw_block() arguments

2022-07-14T18:14:32+00:00

Both submit_bh() and ll_rw_block() accept a request operation type and request flags as their first two arguments. Micro-optimize these two functions by combining these first two arguments into a single argument. This patch does not change the behavior of any of the modified code. Cc: Alexander Viro Cc: Jan Kara Acked-by: Song Liu (for the md changes) Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20220714180729.1065367-48-bvanassche@acm.org Signed-off-by: Jens Axboe

md/core: Combine two sync_page_io() arguments

2022-07-14T18:14:31+00:00

Improve uniformity in the kernel of handling of request operation and flags by passing these as a single argument. Cc: Song Liu Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20220714180729.1065367-32-bvanassche@acm.org Signed-off-by: Jens Axboe

md: replace deprecated strlcpy & remove duplicated line

2022-04-25T21:00:36+00:00

This commit includes two topics: 1> replace deprecated strlcpy change strlcpy to strscpy for strlcpy is marked as deprecated in Documentation/process/deprecated.rst 2> remove duplicated strlcpy line in md_bitmap_read_sb@md-bitmap.c there are two duplicated strlcpy(), the history: - commit cf921cc19cf7 ("Add node recovery callbacks") introduced the first usage of strlcpy(). - commit b97e92574c0b ("Use separate bitmaps for each nodes in the cluster") introduced the second strlcpy(). this time, the two strlcpy() are same, we can remove anyone safely. - commit d3b178adb3a3 ("md: Skip cluster setup for dm-raid") added dm-raid special handling. And the "nodes" value is the key of this patch. but from this patch, strlcpy() which was introduced by b97e92574c0bf become necessary. - commit 3c462c880b52 ("md: Increment version for clustered bitmaps") used clustered major version to only handle in clustered env. this patch could look a polishment for clustered code logic. So cf921cc19cf7 became useless after d3b178adb3a3a, we could remove it safely. Signed-off-by: Heming Zhao Signed-off-by: Song Liu