kernel/linux.git/fs/f2fs/gc.c, branch linux-7.1.y

Merge tag 'f2fs-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2026-04-21T21:50:04+00:00

Pull f2fs updates from Jaegeuk Kim: "In this round, the changes primarily focus on resolving race conditions, memory safety issues (UAF), and improving the robustness of garbage collection (GC), and folio management. Enhancements: - add page-order information for large folio reads in iostat - add defrag_blocks sysfs node Bug fixes: - fix uninitialized kobject put in f2fs_init_sysfs() - disallow setting an extension to both cold and hot - fix node_cnt race between extent node destroy and writeback - preserve previous reserve_{blocks,node} value when remount - freeze GC and discard threads quickly - fix false alarm of lockdep on cp_global_sem lock - fix data loss caused by incorrect use of nat_entry flag - skip empty sections in f2fs_get_victim - fix inline data not being written to disk in writeback path - fix fsck inconsistency caused by FGGC of node block - fix fsck inconsistency caused by incorrect nat_entry flag usage - call f2fs_handle_critical_error() to set cp_error flag - fix fiemap boundary handling when read extent cache is incomplete - fix use-after-free of sbi in f2fs_compress_write_end_io() - fix UAF caused by decrementing sbi->nr_pages[] in f2fs_write_end_io() - fix incorrect file address mapping when inline inode is unwritten - fix incomplete search range in f2fs_get_victim when f2fs_need_rand_seg is enabled - avoid memory leak in f2fs_rename()" * tag 'f2fs-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (35 commits) f2fs: add page-order information for large folio reads in iostat f2fs: do not support mmap write for large folio f2fs: fix uninitialized kobject put in f2fs_init_sysfs() f2fs: protect extension_list reading with sb_lock in f2fs_sbi_show() f2fs: disallow setting an extension to both cold and hot f2fs: fix node_cnt race between extent node destroy and writeback f2fs: allow empty mount string for Opt_usr|grp|projjquota f2fs: fix to preserve previous reserve_{blocks,node} value when remount f2fs: invalidate block device page cache on umount f2fs: fix to freeze GC and discard threads quickly f2fs: fix to avoid uninit-value access in f2fs_sanity_check_node_footer f2fs: fix false alarm of lockdep on cp_global_sem lock f2fs: fix data loss caused by incorrect use of nat_entry flag f2fs: fix to skip empty sections in f2fs_get_victim f2fs: fix inline data not being written to disk in writeback path f2fs: fix fsck inconsistency caused by FGGC of node block f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage f2fs: fix to do sanity check on dcc->discard_cmd_cnt conditionally f2fs: refactor node footer flag setting related code f2fs: refactor f2fs_move_node_folio function ...

f2fs: fix to freeze GC and discard threads quickly

2026-04-02T16:24:20+00:00

Suspend can fail if kernel threads do not freeze for a while. f2fs_gc and f2fs_discard threads can perform long-running operations that prevent them from reaching a freeze point in a timely manner. This patch adds explicit freezing checks in the following locations: 1. f2fs_gc: Added a check at the 'retry' label to exit the loop quickly if freezing is requested, especially during heavy GC rounds. 2. __issue_discard_cmd: Added a 'suspended' flag to break both inner and outer loops during discard command issuance if freezing is detected after at least one command has been issued. 3. __issue_discard_cmd_orderly: Added a similar check for orderly discard to ensure responsiveness. These checks ensure that the threads release locks safely and enter the frozen state. Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to skip empty sections in f2fs_get_victim

2026-04-02T16:24:19+00:00

In age-based victim selection (ATGC, AT_SSR, or GC_CB), f2fs_get_victim can encounter sections with zero valid blocks. This situation often arises when checkpoint is disabled or due to race conditions between SIT updates and dirty list management. In such cases, f2fs_get_section_mtime() returns INVALID_MTIME, which subsequently triggers a fatal f2fs_bug_on(sbi, mtime == INVALID_MTIME) in add_victim_entry() or get_cb_cost(). This patch adds a check in f2fs_get_victim's selection loop to skip sections with no valid blocks. This prevents unnecessary age calculations for empty sections and avoids the associated kernel panic. This change also allows removing redundant checks in add_victim_entry(). Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: avoid reading already updated pages during GC

2026-03-24T17:21:00+00:00

We found the following issue during fuzz testing: page: refcount:3 mapcount:0 mapping:00000000b6e89c65 index:0x18b2dc pfn:0x161ba9 memcg:f8ffff800e269c00 aops:f2fs_meta_aops ino:2 flags: 0x52880000000080a9(locked|waiters|uptodate|lru|private|zone=1|kasantag=0x4a) raw: 52880000000080a9 fffffffec6e17588 fffffffec0ccc088 a7ffff8067063618 raw: 000000000018b2dc 0000000000000009 00000003ffffffff f8ffff800e269c00 page dumped because: VM_BUG_ON_FOLIO(folio_test_uptodate(folio)) page_owner tracks the page as allocated post_alloc_hook+0x58c/0x5ec prep_new_page+0x34/0x284 get_page_from_freelist+0x2dcc/0x2e8c __alloc_pages_noprof+0x280/0x76c __folio_alloc_noprof+0x18/0xac __filemap_get_folio+0x6bc/0xdc4 pagecache_get_page+0x3c/0x104 do_garbage_collect+0x5c78/0x77a4 f2fs_gc+0xd74/0x25f0 gc_thread_func+0xb28/0x2930 kthread+0x464/0x5d8 ret_from_fork+0x10/0x20 ------------[ cut here ]------------ kernel BUG at mm/filemap.c:1563! folio_end_read+0x140/0x168 f2fs_finish_read_bio+0x5c4/0xb80 f2fs_read_end_io+0x64c/0x708 bio_endio+0x85c/0x8c0 blk_update_request+0x690/0x127c scsi_end_request+0x9c/0xb8c scsi_io_completion+0xf0/0x250 scsi_finish_command+0x430/0x45c scsi_complete+0x178/0x6d4 blk_mq_complete_request+0xcc/0x104 scsi_done_internal+0x214/0x454 scsi_done+0x24/0x34 which is similar to the problem reported by syzbot: https://syzkaller.appspot.com/bug?extid=3686758660f980b402dc This case is consistent with the description in commit 9bf1a3f ("f2fs: avoid GC causing encrypted file corrupted"): Page 1 is moved from blkaddr A to blkaddr B by move_data_block, and after being written it is marked as uptodate. Then, Page 1 is moved from blkaddr B to blkaddr C, VM_BUG_ON_FOLIO was triggered in the endio initiated by ra_data_block. There is no need to read Page 1 again from blkaddr B, since it has already been updated. Therefore, avoid initiating I/O in this case. Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC") Signed-off-by: Jianan Huang Signed-off-by: Sheng Yong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs:Fix incomplete search range in f2fs_get_victim when f2fs_need_rand_seg is enabled

2026-03-24T17:20:59+00:00

During the f2fs_get_victim process, when the f2fs_need_rand_seg is enabled in select_policy, p->offset is a random value, and the search range is from p->offset to MAIN_SECS. When segno >= last_segment, the loop breaks and exits directly without searching the range from 0 to p->offset.This results in an incomplete search when the random offset is not zero. Signed-off-by: liujinbao1 Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

treewide: change inode->i_ino from unsigned long to u64

2026-03-06T13:31:28+00:00

On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Chuck Lever Signed-off-by: Christian Brauner

f2fs: sysfs: introduce critical_task_priority

2026-02-10T20:53:21+00:00

This patch introduces /sys/fs/f2fs//critical_task_priority, w/ this new sysfs interface, we can tune priority of f2fs_ckpt thread and f2fs_gc thread. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: support non-4KB block size without packed_ssa feature

2026-01-17T00:00:34+00:00

Currently, F2FS requires the packed_ssa feature to be enabled when utilizing non-4KB block sizes (e.g., 16KB). This restriction limits the flexibility of filesystem formatting options. This patch allows F2FS to support non-4KB block sizes even when the packed_ssa feature is disabled. It adjusts the SSA calculation logic to correctly handle summary entries in larger blocks without the packed layout. Cc: stable@kernel.org Fixes: 7ee8bc3942f2 ("f2fs: revert summary entry count from 2048 to 512 in 16kb block support") Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: trace elapsed time for cp_global_sem lock

2026-01-07T03:17:07+00:00

Use f2fs_{down,up}_write_trace for cp_global_sem to trace lock elapsed time. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: trace elapsed time for gc_lock lock

2026-01-07T03:17:07+00:00

Use f2fs_{down,up}_write_trace for gc_lock to trace lock elapsed time. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim