kernel/linux.git/drivers/md/md.c, branch v7.0.11

md/md-bitmap: add a none backend for bitmap grow

2026-05-23T11:09:30+00:00

[ Upstream commit f2926a533d03fe70d753b512b713e06a2aa174af ] Add a real none bitmap backend that exposes the common bitmap sysfs group and use it to keep bitmap/location available when an array has no bitmap. Then switch the bitmap location sysfs path to move only between none and the classic bitmap backend, using the no-sysfs bitmap helpers while merging or unmerging the internal bitmap sysfs group. This restores mdadm --grow bitmap addition through bitmap/location. Fixes: fb8cc3b0d9db ("md/md-bitmap: delay registration of bitmap_ops until creating bitmap") Reviewed-by: Su Yue Link: https://lore.kernel.org/r/20260425024615.1696892-4-yukuai@fnnas.com Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin

md/md-bitmap: split bitmap sysfs groups

2026-05-23T11:09:30+00:00

[ Upstream commit aba3d6d6cb55c6e1116d1215140559dd7ecdf9a9 ] Split the classic bitmap sysfs files into a common bitmap group with the location attribute and a separate internal bitmap group for the remaining files. At the same time, convert bitmap operations from a single sysfs group to a sysfs group array so backends can share part of their sysfs layout while adding backend-specific attributes separately. Switch the bitmap sysfs helpers to use sysfs_update_groups() for the add and update path, and remove groups in reverse order so shared named groups are unmerged before the last group removes the directory. Also make bitmap operation lookup depend only on the currently selected bitmap id matching the installed backend. This prepares the lookup path for a later registered none backend. Reviewed-by: Su Yue Link: https://lore.kernel.org/r/20260425024615.1696892-3-yukuai@fnnas.com Signed-off-by: Yu Kuai Stable-dep-of: f2926a533d03 ("md/md-bitmap: add a none backend for bitmap grow") Signed-off-by: Sasha Levin

md: factor bitmap creation away from sysfs handling

2026-05-23T11:09:30+00:00

[ Upstream commit 8776d342cf8fa0b98ca5e6fb2d956966fb5ca364 ] Factor bitmap creation and destruction into helpers that do not touch bitmap sysfs registration. This prepares the bitmap sysfs rework so callers such as the sysfs bitmap location path can create or destroy a bitmap backend without coupling that to sysfs group lifetime management. Reviewed-by: Su Yue Link: https://lore.kernel.org/r/20260425024615.1696892-2-yukuai@fnnas.com Signed-off-by: Yu Kuai Stable-dep-of: f2926a533d03 ("md/md-bitmap: add a none backend for bitmap grow") Signed-off-by: Sasha Levin

md: add fallback to correct bitmap_ops on version mismatch

2026-05-23T11:09:30+00:00

[ Upstream commit 09af773650024279a60348e7319d599e6571b15c ] If default bitmap version and on-disk version doesn't match, and mdadm is not the latest version to set bitmap_type, set bitmap_ops based on the disk version. Link: https://lore.kernel.org/linux-raid/20260323054644.3351791-2-yukuai@fnnas.com/ Signed-off-by: Yu Kuai Stable-dep-of: f2926a533d03 ("md/md-bitmap: add a none backend for bitmap grow") Signed-off-by: Sasha Levin

md: wake raid456 reshape waiters before suspend

2026-05-23T11:08:27+00:00

[ Upstream commit cf86bb53b9c92354904a328e947a05ffbfdd1840 ] During raid456 reshape, direct IO across the reshape position can sleep in raid5_make_request() waiting for reshape progress while still holding an active_io reference. If userspace then freezes reshape and writes md/suspend_lo or md/suspend_hi, mddev_suspend() kills active_io and waits for all in-flight IO to drain. This can deadlock: the IO needs reshape progress to continue, but the reshape thread is already frozen, so the active_io reference is never dropped and suspend never completes. raid5_prepare_suspend() already wakes wait_for_reshape for dm-raid. Do the same for normal md suspend when reshape is already interrupted, so waiting raid456 IO can abort, drop its reference, and let suspend finish. The mdadm test tests/25raid456-reshape-deadlock reproduces the hang. Fixes: 714d20150ed8 ("md: add new helpers to suspend/resume array") Link: https://lore.kernel.org/linux-raid/20260327140729.2030564-1-yukuai@fnnas.com/ Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin

md: remove unused static md_wq workqueue

2026-05-23T11:08:27+00:00

[ Upstream commit e4979f4fac4d6bbe757be50441b45e28e6bf7360 ] The md_wq workqueue is defined as static and initialized in md_init(), but it is not used anywhere within md.c. All asynchronous and deferred work in this file is handled via md_misc_wq or dedicated md threads. Fixes: b75197e86e6d3 ("md: Remove flush handling") Signed-off-by: Abd-Alrhman Masalkhi Link: https://lore.kernel.org/linux-raid/20260328193522.3624-1-abd.masalkhi@gmail.com/ Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin

md: fix array_state=clear sysfs deadlock

2026-05-23T11:08:27+00:00

[ Upstream commit 2aa72276fab9851dbd59c2daeb4b590c5a113908 ] When "clear" is written to array_state, md_attr_store() breaks sysfs active protection so the array can delete itself from its own sysfs store method. However, md_attr_store() currently drops the mddev reference before calling sysfs_unbreak_active_protection(). Once do_md_stop(..., 0) has made the mddev eligible for delayed deletion, the temporary kobject reference taken by sysfs_break_active_protection() can become the last kobject reference protecting the md kobject. That allows sysfs_unbreak_active_protection() to drop the last kobject reference from the current sysfs writer context. kobject teardown then recurses into kernfs removal while the current sysfs node is still being unwound, and lockdep reports recursive locking on kn->active with kernfs_drain() in the call chain. Reproducer on an existing level: 1. Create an md0 linear array and activate it: mknod /dev/md0 b 9 0 echo none > /sys/block/md0/md/metadata_version echo linear > /sys/block/md0/md/level echo 1 > /sys/block/md0/md/raid_disks echo "$(cat /sys/class/block/sdb/dev)" > /sys/block/md0/md/new_dev echo "$(($(cat /sys/class/block/sdb/size) / 2))" > \ /sys/block/md0/md/dev-sdb/size echo 0 > /sys/block/md0/md/dev-sdb/slot echo active > /sys/block/md0/md/array_state 2. Wait briefly for the array to settle, then clear it: sleep 2 echo clear > /sys/block/md0/md/array_state The warning looks like: WARNING: possible recursive locking detected bash/588 is trying to acquire lock: (kn->active#65) at __kernfs_remove+0x157/0x1d0 but task is already holding lock: (kn->active#65) at sysfs_unbreak_active_protection+0x1f/0x40 ... Call Trace: kernfs_drain __kernfs_remove kernfs_remove_by_name_ns sysfs_remove_group sysfs_remove_groups __kobject_del kobject_put md_attr_store kernfs_fop_write_iter vfs_write ksys_write Restore active protection before mddev_put() so the extra sysfs kobject reference is dropped while the mddev is still held alive. The actual md kobject deletion is then deferred until after the sysfs write path has fully returned. Fixes: 9e59d609763f ("md: call del_gendisk in control path") Reviewed-by: Xiao Ni Link: https://lore.kernel.org/linux-raid/20260330055213.3976052-1-yukuai@fnnas.com/ Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin

md: suppress spurious superblock update error message for dm-raid

2026-05-23T11:08:26+00:00

[ Upstream commit eff0d74c6c8fd358bc9474c05002e51fa5aa56ad ] dm-raid has external metadata management (mddev->external = 1) and no persistent superblock (mddev->persistent = 0). For these arrays, there's no superblock to update, so the error message is spurious. The error appears as: md_update_sb: can't update sb for read-only array md0 Fixes: 8c9e376b9d1a ("md: warn about updating super block failure") Reported-by: Tj Closes: https://lore.kernel.org/all/20260128082430.96788-1-tj.iam.tj@proton.me/ Signed-off-by: Chen Cheng Reviewed-by: Paul Menzel Link: https://lore.kernel.org/linux-raid/20260210133847.269986-1-chencheng@fnnas.com Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook