kernel.git/fs/fs-writeback.c, branch master

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

2026-02-25T18:34:23Z

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_flex' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51Z

This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28Z

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

writeback: Fix wakeup and logging timeouts for !DETECT_HUNG_TASK

2026-02-14T12:17:46Z

Recent changes of fs-writeback cause such warnings if DETECT_HUNG_TASK is not enabled: INFO: The task sync:1342 has been waiting for writeback completion for more than 1 seconds. The reason is sysctl_hung_task_timeout_secs is 0 when DETECT_HUNG_TASK is not enabled, then it causes the warning message even if the writeback lasts for only one second. Guard the wakeup and logging with "#ifdef CONFIG_DETECT_HUNG_TASK" can eliminate the warning messages. But on the other hand, it is possible that sysctl_hung_task_timeout_secs be also 0 when DETECT_HUNG_TASK is enabled. So let's just check the value of sysctl_hung_task_timeout_secs to decide whether do wakeup and logging. Fixes: 1888635532fb ("writeback: Wake up waiting tasks when finishing the writeback of a chunk.") Fixes: d6e621590764 ("writeback: Add logging for slow writeback (exceeds sysctl_hung_task_timeout_secs)") Signed-off-by: Huacai Chen Link: https://patch.msgid.link/20260203094014.2273240-1-chenhuacai@loongson.cn Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

Merge tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2026-02-11T21:20:50Z

Pull cgroup updates from Tejun Heo: - cpuset changes: - Continue separating v1 and v2 implementations by moving more v1-specific logic into cpuset-v1.c - Improve partition handling. Sibling partitions are no longer invalidated on cpuset.cpus conflict, cpuset.cpus changes no longer fail in v2, and effective_xcpus computation is made consistent - Fix partition effective CPUs overlap that caused a warning on cpuset removal when sibling partitions shared CPUs - Increase the maximum cgroup subsystem count from 16 to 32 to accommodate future subsystem additions - Misc cleanups and selftest improvements including switching to css_is_online() helper, removing dead code and stale documentation references, using lockdep_assert_cpuset_lock_held() consistently, and adding polling helpers for asynchronously updated cgroup statistics * tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits) cpuset: fix overlap of partition effective CPUs cgroup: increase maximum subsystem count from 16 to 32 cgroup: Remove stale cpu.rt.max reference from documentation cpuset: replace direct lockdep_assert_held() with lockdep_assert_cpuset_lock_held() cgroup/cpuset: Move the v1 empty cpus/mems check to cpuset1_validate_change() cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict cgroup/cpuset: Don't fail cpuset.cpus change in v2 cgroup/cpuset: Consistently compute effective_xcpus in update_cpumasks_hier() cgroup/cpuset: Streamline rm_siblings_excl_cpus() cpuset: remove dead code in cpuset-v1.c cpuset: remove v1-specific code from generate_sched_domains cpuset: separate generate_sched_domains for v1 and v2 cpuset: move update_domain_attr_tree to cpuset_v1.c cpuset: add cpuset1_init helper for v1 initialization cpuset: add cpuset1_online_css helper for v1-specific operations cpuset: add lockdep_assert_cpuset_lock_held helper cpuset: Remove unnecessary checks in rebuild_sched_domains_locked cgroup: switch to css_is_online() helper selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on nr_dying_descendants selftests: cgroup: make test_memcg_sock robust against delayed sock stats ...

Merge tag 'vfs-7.0-rc1.nonblocking_timestamps' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-02-09T19:25:01Z

Pull vfs timestamp updates from Christian Brauner: "This contains the changes to support non-blocking timestamp updates. Since commit 66fa3cedf16a ("fs: Add async write file modification handling") file_update_time_flags() unconditionally returns -EAGAIN when any timestamp needs updating and IOCB_NOWAIT is set. This makes non-blocking direct writes impossible on file systems with granular enough timestamps, which in practice means all of them. This reworks the timestamp update path to propagate IOCB_NOWAIT through ->update_time so that file systems which can update timestamps without blocking are no longer penalized. With that groundwork in place, the core change passes IOCB_NOWAIT into ->update_time and returns -EAGAIN only when the file system indicates it would block. XFS implements non-blocking timestamp updates by using the new ->sync_lazytime and open-coding generic_update_time without the S_NOWAIT check, since the lazytime path through the generic helpers can never block in XFS" * tag 'vfs-7.0-rc1.nonblocking_timestamps' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: xfs: enable non-blocking timestamp updates xfs: implement ->sync_lazytime fs: refactor file_update_time_flags fs: add support for non-blocking timestamp updates fs: add a ->sync_lazytime method fs: factor out a sync_lazytime helper fs: refactor ->update_time handling fat: cleanup the flags for fat_truncate_time nfs: split nfs_update_timestamps fs: allow error returns from generic_update_time fs: remove inode_update_time

Merge tag 'vfs-6.19-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-01-26T17:30:48Z

Pull vfs fixes from Christian Brauner: - Fix the the buggy conversion of fuse_reverse_inval_entry() introduced during the creation rework - Disallow nfs delegation requests for directories by setting simple_nosetlease() - Require an opt-in for getting readdir flag bits outside of S_DT_MASK set in d_type - Fix scheduling delayed writeback work by only scheduling when the dirty time expiry interval is non-zero and cancel the delayed work if the interval is set to zero - Use rounded_jiffies_interval for dirty time work - Check the return value of sb_set_blocksize() for romfs - Wait for batched folios to be stable in __iomap_get_folio() - Use private naming for fuse hash size - Fix the stale dentry cleanup to prevent a race that causes a UAF * tag 'vfs-6.19-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: vfs: document d_dispose_if_unused() fuse: shrink once after all buckets have been scanned fuse: clean up fuse_dentry_tree_work() fuse: add need_resched() before unlocking bucket fuse: make sure dentry is evicted if stale fuse: fix race when disposing stale dentries fuse: use private naming for fuse hash size writeback: use round_jiffies_relative for dirtytime_work iomap: wait for batched folios to be stable in __iomap_get_folio romfs: check sb_set_blocksize() return value docs: clarify that dirtytime_expire_seconds=0 disables writeback writeback: fix 100% CPU usage when dirtytime_expire_interval is 0 readdir: require opt-in for d_type flags vboxsf: don't allow delegations to be set on directories ceph: don't allow delegations to be set on directories gfs2: don't allow delegations to be set on directories 9p: don't allow delegations to be set on directories smb/client: properly disallow delegations on directories nfs: properly disallow delegation requests on directories fuse: fix conversion of fuse_reverse_inval_entry() to start_removing()

fs/writeback: skip AS_NO_DATA_INTEGRITY mappings in wait_sb_inodes()

2026-01-19T20:30:01Z

Above the while() loop in wait_sb_inodes(), we document that we must wait for all pages under writeback for data integrity. Consequently, if a mapping, like fuse, traditionally does not have data integrity semantics, there is no need to wait at all; we can simply skip these inodes. This restores fuse back to prior behavior where syncs are no-ops. This fixes a user regression where if a system is running a faulty fuse server that does not reply to issued write requests, this causes wait_sb_inodes() to wait forever. Link: https://lkml.kernel.org/r/20260105211737.4105620-2-joannelkoong@gmail.com Fixes: 0c58a97f919c ("fuse: remove tmp folio for writebacks and internal rb tree") Signed-off-by: Joanne Koong Reported-by: Athul Krishna Reported-by: J. Neuschäfer Reviewed-by: Bernd Schubert Tested-by: J. Neuschäfer Cc: Alexander Viro Cc: Bernd Schubert Cc: Bonaccorso Salvatore Cc: Christian Brauner Cc: David Hildenbrand Cc: Jan Kara Cc: "Liam R. Howlett" Cc: Lorenzo Stoakes Cc: "Matthew Wilcox (Oracle)" Cc: Michal Hocko Cc: Mike Rapoport Cc: Miklos Szeredi Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Signed-off-by: Andrew Morton

writeback: use round_jiffies_relative for dirtytime_work

2026-01-14T16:11:43Z

The dirtytime_work is a background housekeeping task that flushes dirty inodes, using round_jiffies_relative() will allow kernel to batch this work with other aligned system tasks, reducing power consumption. Signed-off-by: Zhao Mengmeng Link: https://patch.msgid.link/20260113082614.231580-1-zhaomzhao@126.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

fs: add a ->sync_lazytime method

2026-01-12T13:01:33Z

Allow the file system to explicitly implement lazytime syncing instead of pigging back on generic inode dirtying. This allows to simplify the XFS implementation and prepares for non-blocking lazytime timestamp updates. Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260108141934.2052404-8-hch@lst.de Reviewed-by: Chaitanya Kulkarni Reviewed-by: Jeff Layton Reviewed-by: Jan Kara Signed-off-by: Christian Brauner