kernel/linux.git/fs/iomap, branch v7.0.10

iomap: fix lockdep complaint when reads fail

2026-03-24T08:14:46+00:00

Zorro Lang reported the following lockdep splat: "While running fstests xfs/556 on kernel 7.0.0-rc4+ (HEAD=04a9f1766954), a lockdep warning was triggered indicating an inconsistent lock state for sb->s_type->i_lock_key. "The deadlock might occur because iomap_read_end_io (called from a hardware interrupt completion path) invokes fserror_report, which then calls igrab. igrab attempts to acquire the i_lock spinlock. However, the i_lock is frequently acquired in process context with interrupts enabled. If an interrupt occurs while a process holds the i_lock, and that interrupt handler calls fserror_report, the system deadlocks. "I hit this warning several times by running xfs/556 (mostly) or generic/648 on xfs. More details refer to below console log." along with this dmesg, for which I've cleaned up the stacktraces: run fstests xfs/556 at 2026-03-18 20:05:30 XFS (sda3): Mounting V5 Filesystem 396e9164-c45a-4e05-be9d-b38c2c5c6477 XFS (sda3): Ending clean mount XFS (sda3): Unmounting Filesystem 396e9164-c45a-4e05-be9d-b38c2c5c6477 XFS (sda3): Mounting V5 Filesystem bf3f89c3-3c45-4650-a9c7-744f39c0191e XFS (sda3): Ending clean mount XFS (sda3): Unmounting Filesystem bf3f89c3-3c45-4650-a9c7-744f39c0191e XFS (dm-0): Mounting V5 Filesystem bf3f89c3-3c45-4650-a9c7-744f39c0191e XFS (dm-0): Ending clean mount device-mapper: table: 253:0: adding target device (start sect 209 len 1) caused an alignment inconsistency device-mapper: table: 253:0: adding target device (start sect 210 len 62914350) caused an alignment inconsistency buffer_io_error: 6 callbacks suppressed Buffer I/O error on dev dm-0, logical block 209, async page read Buffer I/O error on dev dm-0, logical block 209, async page read XFS (dm-0): Unmounting Filesystem bf3f89c3-3c45-4650-a9c7-744f39c0191e XFS (dm-0): Mounting V5 Filesystem bf3f89c3-3c45-4650-a9c7-744f39c0191e XFS (dm-0): Ending clean mount ================================ WARNING: inconsistent lock state 7.0.0-rc4+ #1 Tainted: G S W -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. od/2368602 [HC1[1]:SC0[0]:HE0:SE1] takes: ff1100069f2b4a98 (&sb->s_type->i_lock_key#31){?.+.}-{3:3}, at: igrab+0x28/0x1a0 {HARDIRQ-ON-W} state was registered at: __lock_acquire+0x40d/0xbd0 lock_acquire.part.0+0xbd/0x260 _raw_spin_lock+0x37/0x80 unlock_new_inode+0x66/0x2a0 xfs_iget+0x67b/0x7b0 [xfs] xfs_mountfs+0xde4/0x1c80 [xfs] xfs_fs_fill_super+0xe86/0x17a0 [xfs] get_tree_bdev_flags+0x312/0x590 vfs_get_tree+0x8d/0x2f0 vfs_cmd_create+0xb2/0x240 __do_sys_fsconfig+0x3d8/0x9a0 do_syscall_64+0x13a/0x1520 entry_SYSCALL_64_after_hwframe+0x76/0x7e irq event stamp: 3118 hardirqs last enabled at (3117): [] _raw_spin_unlock_irq+0x28/0x50 hardirqs last disabled at (3118): [] common_interrupt+0x19/0xe0 softirqs last enabled at (3040): [] handle_softirqs+0x6b8/0x950 softirqs last disabled at (3023): [] __irq_exit_rcu+0xfd/0x250 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sb->s_type->i_lock_key#31); lock(&sb->s_type->i_lock_key#31); *** DEADLOCK *** 1 lock held by od/2368602: #0: ff1100069f2b4b58 (&sb->s_type->i_mutex_key#19){++++}-{4:4}, at: xfs_ilock+0x324/0x4b0 [xfs] stack backtrace: CPU: 15 UID: 0 PID: 2368602 Comm: od Kdump: loaded Tainted: G S W 7.0.0-rc4+ #1 PREEMPT(full) Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN Hardware name: Dell Inc. PowerEdge R660/0R5JJC, BIOS 2.1.5 03/14/2024 Call Trace: dump_stack_lvl+0x6f/0xb0 print_usage_bug.part.0+0x230/0x2c0 mark_lock_irq+0x3ce/0x5b0 mark_lock+0x1cb/0x3d0 mark_usage+0x109/0x120 __lock_acquire+0x40d/0xbd0 lock_acquire.part.0+0xbd/0x260 _raw_spin_lock+0x37/0x80 igrab+0x28/0x1a0 fserror_report+0x127/0x2d0 iomap_finish_folio_read+0x13c/0x280 iomap_read_end_io+0x10e/0x2c0 clone_endio+0x37e/0x780 [dm_mod] blk_update_request+0x448/0xf00 scsi_end_request+0x74/0x750 scsi_io_completion+0xe9/0x7c0 _scsih_io_done+0x6ba/0x1ca0 [mpt3sas] _base_process_reply_queue+0x249/0x15b0 [mpt3sas] _base_interrupt+0x95/0xe0 [mpt3sas] __handle_irq_event_percpu+0x1f0/0x780 handle_irq_event+0xa9/0x1c0 handle_edge_irq+0x2ef/0x8a0 __common_interrupt+0xa0/0x170 common_interrupt+0xb7/0xe0 asm_common_interrupt+0x26/0x40 RIP: 0010:_raw_spin_unlock_irq+0x2e/0x50 Code: 0f 1f 44 00 00 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 b5 73 5e fd 48 89 df e8 ed e2 5e fd e8 08 78 8f fd fb bf 01 00 00 00 8d 56 4d fd 65 8b 05 46 d5 1d 03 85 c0 74 06 5b c3 cc cc cc cc RSP: 0018:ffa0000027d07538 EFLAGS: 00000206 RAX: 0000000000000c2d RBX: ffffffffb6614bc8 RCX: 0000000000000080 RDX: 0000000000000000 RSI: ffffffffb6306a01 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffffb75efc67 R11: 0000000000000001 R12: ff1100015ada0000 R13: 0000000000000083 R14: 0000000000000002 R15: ffffffffb6614c10 folio_wait_bit_common+0x407/0x780 filemap_update_page+0x8e7/0xbd0 filemap_get_pages+0x904/0xc50 filemap_read+0x320/0xc20 xfs_file_buffered_read+0x2aa/0x380 [xfs] xfs_file_read_iter+0x263/0x4a0 [xfs] vfs_read+0x6cb/0xb70 ksys_read+0xf9/0x1d0 do_syscall_64+0x13a/0x1520 Zorro's diagnosis makes sense, so the solution is to kick the failed read handling to a workqueue much like we added for writeback ioends in commit 294f54f849d846 ("fserror: fix lockdep complaint when igrabbing inode"). Cc: Zorro Lang Link: https://lore.kernel.org/linux-xfs/20260319194303.efw4wcu7c4idhthz@doltdoltdolt/ Fixes: a9d573ee88af98 ("iomap: report file I/O errors to the VFS") Signed-off-by: "Darrick J. Wong" Link: https://patch.msgid.link/20260323210017.GL6223@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

iomap: fix invalid folio access when i_blkbits differs from I/O granularity

2026-03-18T09:42:08+00:00

Commit aa35dd5cbc06 ("iomap: fix invalid folio access after folio_end_read()") partially addressed invalid folio access for folios without an ifs attached, but it did not handle the case where 1 << inode->i_blkbits matches the folio size but is different from the granularity used for the IO, which means IO can be submitted for less than the full folio for the !ifs case. In this case, the condition: if (*bytes_submitted == folio_len) ctx->cur_folio = NULL; in iomap_read_folio_iter() will not invalidate ctx->cur_folio, and iomap_read_end() will still be called on the folio even though the IO helper owns it and will finish the read on it. Fix this by unconditionally invalidating ctx->cur_folio for the !ifs case. Reported-by: Johannes Thumshirn Tested-by: Johannes Thumshirn Link: https://lore.kernel.org/linux-fsdevel/b3dfe271-4e3d-4922-b618-e73731242bca@wdc.com/ Fixes: b2f35ac4146d ("iomap: add caller-provided callbacks for read and readahead") Cc: stable@vger.kernel.org Signed-off-by: Joanne Koong Link: https://patch.msgid.link/20260317203935.830549-1-joannelkoong@gmail.com Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

iomap: reject delalloc mappings during writeback

2026-03-04T13:31:56+00:00

Filesystems should never provide a delayed allocation mapping to writeback; they're supposed to allocate the space before replying. This can lead to weird IO errors and crashes in the block layer if the filesystem is being malicious, or if it hadn't set iomap->dev because it's a delalloc mapping. Fix this by failing writeback on delalloc mappings. Currently no filesystems actually misbehave in this manner, but we ought to be stricter about things like that. Cc: stable@vger.kernel.org # v5.5 Fixes: 598ecfbaa742ac ("iomap: lift the xfs writeback code to iomap") Signed-off-by: Darrick J. Wong Link: https://patch.msgid.link/20260302173002.GL13829@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Reviewed-by: Carlos Maiolino Signed-off-by: Christian Brauner

iomap: don't mark folio uptodate if read IO has bytes pending

2026-03-04T13:18:54+00:00

If a folio has ifs metadata attached to it and the folio is partially read in through an async IO helper with the rest of it then being read in through post-EOF zeroing or as inline data, and the helper successfully finishes the read first, then post-EOF zeroing / reading inline will mark the folio as uptodate in iomap_set_range_uptodate(). This is a problem because when the read completion path later calls iomap_read_end(), it will call folio_end_read(), which sets the uptodate bit using XOR semantics. Calling folio_end_read() on a folio that was already marked uptodate clears the uptodate bit. Fix this by not marking the folio as uptodate if the read IO has bytes pending. The folio uptodate state will be set in the read completion path through iomap_end_read() -> folio_end_read(). Reported-by: Wei Gao Suggested-by: Sasha Levin Tested-by: Wei Gao Reviewed-by: Darrick J. Wong Cc: stable@vger.kernel.org # v6.19 Link: https://lore.kernel.org/linux-fsdevel/aYbmy8JdgXwsGaPP@autotest-wegao.qe.prg2.suse.org/ Fixes: b2f35ac4146d ("iomap: add caller-provided callbacks for read and readahead") Signed-off-by: Joanne Koong Link: https://patch.msgid.link/20260303233420.874231-2-joannelkoong@gmail.com Signed-off-by: Christian Brauner

iomap: don't report direct-io retries to fserror

2026-02-26T08:23:22+00:00

iomap's directio implementation has two magic errno codes that it uses to signal callers -- ENOTBLK tells the filesystem that it should retry a write with the pagecache; and EAGAIN tells the caller that pagecache flushing or invalidation failed and that it should try again. Neither of these indicate data loss, so let's not report them. Fixes: a9d573ee88af98 ("iomap: report file I/O errors to the VFS") Signed-off-by: Darrick J. Wong Link: https://patch.msgid.link/20260224154637.GD2390381@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

Merge tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-25T18:34:23+00:00

Pull vfs fixes from Christian Brauner: - Fix an uninitialized variable in file_getattr(). The flags_valid field wasn't initialized before calling vfs_fileattr_get(), triggering KMSAN uninit-value reports in fuse - Fix writeback wakeup and logging timeouts when DETECT_HUNG_TASK is not enabled. sysctl_hung_task_timeout_secs is 0 in that case causing spurious "waiting for writeback completion for more than 1 seconds" warnings - Fix a null-ptr-deref in do_statmount() when the mount is internal - Add missing kernel-doc description for the @private parameter in iomap_readahead() - Fix mount namespace creation to hold namespace_sem across the mount copy in create_new_namespace(). The previous drop-and-reacquire pattern was fragile and failed to clean up mount propagation links if the real rootfs was a shared or dependent mount - Fix /proc mount iteration where m->index wasn't updated when m->show() overflows, causing a restart to repeatedly show the same mount entry in a rapidly expanding mount table - Return EFSCORRUPTED instead of ENOSPC in minix_new_inode() when the inode number is out of range - Fix unshare(2) when CLONE_NEWNS is set and current->fs isn't shared. copy_mnt_ns() received the live fs_struct so if a subsequent namespace creation failed the rollback would leave pwd and root pointing to detached mounts. Always allocate a new fs_struct when CLONE_NEWNS is requested - fserror bug fixes: - Remove the unused fsnotify_sb_error() helper now that all callers have been converted to fserror_report_metadata - Fix a lockdep splat in fserror_report() where igrab() takes inode::i_lock which can be held in IRQ context. Replace igrab() with a direct i_count bump since filesystems should not report inodes that are about to be freed or not yet exposed - Handle error pointer in procfs for try_lookup_noperm() - Fix an integer overflow in ep_loop_check_proc() where recursive calls returning INT_MAX would overflow when +1 is added, breaking the recursion depth check - Fix a misleading break in pidfs * tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: pidfs: avoid misleading break eventpoll: Fix integer overflow in ep_loop_check_proc() proc: Fix pointer error dereference fserror: fix lockdep complaint when igrabbing inode fsnotify: drop unused helper unshare: fix unshare_fs() handling minix: Correct errno in minix_new_inode namespace: fix proc mount iteration mount: hold namespace_sem across copy in create_new_namespace() iomap: Describe @private in iomap_readahead() statmount: Fix the null-ptr-deref in do_statmount() writeback: Fix wakeup and logging timeouts for !DETECT_HUNG_TASK fs: init flags_valid before calling vfs_fileattr_get

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

fserror: fix lockdep complaint when igrabbing inode

2026-02-19T08:12:08+00:00

Christoph Hellwig reported a lockdep splat in generic/108: ================================ WARNING: inconsistent lock state 6.19.0+ #4827 Tainted: G N -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. swapper/1/0 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff88811ed1b140 (&sb->s_type->i_lock_key#33){?.+.}-{3:3}, at: igrab+0x1a/0xb0 {HARDIRQ-ON-W} state was registered at: lock_acquire+0xca/0x2c0 _raw_spin_lock+0x2e/0x40 unlock_new_inode+0x2c/0xc0 xfs_iget+0xcf4/0x1080 xfs_trans_metafile_iget+0x3d/0x100 xfs_metafile_iget+0x2b/0x50 xfs_mount_setup_metadir+0x20/0x60 xfs_mountfs+0x457/0xa60 xfs_fs_fill_super+0x6b3/0xa90 get_tree_bdev_flags+0x13c/0x1e0 vfs_get_tree+0x27/0xe0 vfs_cmd_create+0x54/0xe0 __do_sys_fsconfig+0x309/0x620 do_syscall_64+0x8b/0xf80 entry_SYSCALL_64_after_hwframe+0x76/0x7e irq event stamp: 139080 hardirqs last enabled at (139079): [] do_idle+0x1ec/0x270 hardirqs last disabled at (139080): [] common_interrupt+0x19/0xe0 softirqs last enabled at (139032): [] __irq_exit_rcu+0xc3/0x120 softirqs last disabled at (139025): [] __irq_exit_rcu+0xc3/0x120 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sb->s_type->i_lock_key#33); lock(&sb->s_type->i_lock_key#33); *** DEADLOCK *** 1 lock held by swapper/1/0: #0: ffff8881052c81a0 (&vblk->vqs[i].lock){-.-.}-{3:3}, at: virtblk_done+0x4b/0x110 stack backtrace: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G N 6.19.0+ #4827 PREEMPT(full) Tainted: [N]=TEST Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x5b/0x80 print_usage_bug.part.0+0x22c/0x2c0 mark_lock+0xa6f/0xe90 __lock_acquire+0x10b6/0x25e0 lock_acquire+0xca/0x2c0 _raw_spin_lock+0x2e/0x40 igrab+0x1a/0xb0 fserror_report+0x135/0x260 iomap_finish_ioend_buffered+0x170/0x210 clone_endio+0x8f/0x1c0 blk_update_request+0x1e4/0x4d0 blk_mq_end_request+0x1b/0x100 virtblk_done+0x6f/0x110 vring_interrupt+0x59/0x80 __handle_irq_event_percpu+0x8a/0x2e0 handle_irq_event+0x33/0x70 handle_edge_irq+0xdd/0x1e0 __common_interrupt+0x6f/0x180 common_interrupt+0xb7/0xe0 It looks like the concern here is that inode::i_lock is sometimes taken in IRQ context, and sometimes it is held when going to IRQ context, though it's a little difficult to tell since I think this is a kernel from after the actual 6.19 release but before 7.0-rc1. Either way, we don't need to take i_lock, because filesystems should not report files to fserror if they're about to be freed or have not yet been exposed to other threads, because the resulting fsnotify report will be meaningless. Therefore, bump inode::i_count directly and clarify the preconditions on the inode being passed in. Link: https://lore.kernel.org/linux-fsdevel/aY7BndIgQg3ci_6s@infradead.org/ Reported-by: Christoph Hellwig Signed-off-by: Darrick J. Wong Link: https://patch.msgid.link/177148129564.716249.3069780698231701540.stgit@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

iomap: Describe @private in iomap_readahead()

2026-02-14T12:24:44+00:00

The kernel test rebot reports the kernel-doc warning: ``` Warning: fs/iomap/buffered-io.c:624 function parameter 'private' not described in 'iomap_readahead' ``` The former commit in "iomap: stash iomap read ctx in the private field of iomap_iter" has added a new parameter @private to iomap_readahead(), so let's describe the parameter. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202601261111.vIL9rhgD-lkp@intel.com/ Fixes: 8806f279244b ("iomap: stash iomap read ctx in the private field of iomap_iter") Signed-off-by: Hongbo Li Link: https://patch.msgid.link/20260213022812.766187-1-lihongbo22@huawei.com Reviewed-by: Gao Xiang Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner