kernel.git/include/trace/events/btrfs.h, branch linux-6.12.y

btrfs: fix NULL dereference on root when tracing inode eviction

2026-01-17T15:31:20Z

[ Upstream commit f157dd661339fc6f5f2b574fe2429c43bd309534 ] When evicting an inode the first thing we do is to setup tracing for it, which implies fetching the root's id. But in btrfs_evict_inode() the root might be NULL, as implied in the next check that we do in btrfs_evict_inode(). Hence, we either should set the ->root_objectid to 0 in case the root is NULL, or we move tracing setup after checking that the root is not NULL. Setting the rootid to 0 at least gives us the possibility to trace this call even in the case when the root is NULL, so that's the solution taken here. Fixes: 1abe9b8a138c ("Btrfs: add initial tracepoint support for btrfs") Reported-by: syzbot+d991fea1b4b23b1f6bf8@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d991fea1b4b23b1f6bf8 Signed-off-by: Miquel Sabaté Solà Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: tracepoints: use btrfs_root_id() to get the id of a root

2026-01-17T15:31:20Z

[ Upstream commit 0f987c099d22c3b8c7d94fd13f957792e46f79c9 ] Instead of open coding btrfs_root_id() to get the ID of a root, use the helper in the trace points, which also makes the code less verbose. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: f157dd661339 ("btrfs: fix NULL dereference on root when tracing inode eviction") Signed-off-by: Sasha Levin

btrfs: correct the order of prelim_ref arguments in btrfs__prelim_ref

2025-05-29T09:03:12Z

[ Upstream commit bc7e0975093567f51be8e1bdf4aa5900a3cf0b1e ] btrfs_prelim_ref() calls the old and new reference variables in the incorrect order. This causes a NULL pointer dereference because oldref is passed as NULL to trace_btrfs_prelim_ref_insert(). Note, trace_btrfs_prelim_ref_insert() is being called with newref as oldref (and oldref as NULL) on purpose in order to print out the values of newref. To reproduce: echo 1 > /sys/kernel/debug/tracing/events/btrfs/btrfs_prelim_ref_insert/enable Perform some writeback operations. Backtrace: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 115949067 P4D 115949067 PUD 11594a067 PMD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 1188 Comm: fsstress Not tainted 6.15.0-rc2-tester+ #47 PREEMPT(voluntary) 7ca2cef72d5e9c600f0c7718adb6462de8149622 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-2-gc13ff2cd-prebuilt.qemu.org 04/01/2014 RIP: 0010:trace_event_raw_event_btrfs__prelim_ref+0x72/0x130 Code: e8 43 81 9f ff 48 85 c0 74 78 4d 85 e4 0f 84 8f 00 00 00 49 8b 94 24 c0 06 00 00 48 8b 0a 48 89 48 08 48 8b 52 08 48 89 50 10 <49> 8b 55 18 48 89 50 18 49 8b 55 20 48 89 50 20 41 0f b6 55 28 88 RSP: 0018:ffffce44820077a0 EFLAGS: 00010286 RAX: ffff8c6b403f9014 RBX: ffff8c6b55825730 RCX: 304994edf9cf506b RDX: d8b11eb7f0fdb699 RSI: ffff8c6b403f9010 RDI: ffff8c6b403f9010 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000010 R10: 00000000ffffffff R11: 0000000000000000 R12: ffff8c6b4e8fb000 R13: 0000000000000000 R14: ffffce44820077a8 R15: ffff8c6b4abd1540 FS: 00007f4dc6813740(0000) GS:ffff8c6c1d378000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000010eb42000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: prelim_ref_insert+0x1c1/0x270 find_parent_nodes+0x12a6/0x1ee0 ? __entry_text_end+0x101f06/0x101f09 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 btrfs_is_data_extent_shared+0x167/0x640 ? fiemap_process_hole+0xd0/0x2c0 extent_fiemap+0xa5c/0xbc0 ? __entry_text_end+0x101f05/0x101f09 btrfs_fiemap+0x7e/0xd0 do_vfs_ioctl+0x425/0x9d0 __x64_sys_ioctl+0x75/0xc0 Signed-off-by: Goldwyn Rodrigues Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: tracepoints: end assignment with semicolon at btrfs_qgroup_extent event class

2024-10-01T17:14:10Z

While running checkpatch.pl against a patch that modifies the btrfs_qgroup_extent event class, it complained about using a comma instead of a semicolon: $ ./scripts/checkpatch.pl qgroups/0003-btrfs-qgroups-remove-bytenr-field-from-struct-btrfs_.patch WARNING: Possible comma where semicolon could be used #215: FILE: include/trace/events/btrfs.h:1720: + __entry->bytenr = bytenr, __entry->num_bytes = rec->num_bytes; total: 0 errors, 1 warnings, 184 lines checked So replace the comma with a semicolon to silence checkpatch and possibly other tools. It also makes the code consistent with the rest. Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: constify more pointer parameters

2024-09-10T14:51:22Z

Continue adding const to parameters. This is for clarity and minor addition to safety. There are some minor effects, in the assembly code and .ko measured on release config. Signed-off-by: David Sterba

btrfs: rename __extent_writepage() and drop double underscores

2024-09-10T14:51:19Z

The function does not follow the pattern where the underscores would be justified, so rename it. Reviewed-by: Qu Wenruo Signed-off-by: David Sterba

btrfs: update the writepage tracepoint to take a folio

2024-09-10T14:51:13Z

Willy is wanting to get rid of page->index, convert the writepage tracepoint to take a folio so we can do folio->index instead of page->index. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2024-07-31T02:28:36Z

Pull btrfs fixes from David Sterba: - fix regression in extent map rework when handling insertion of overlapping compressed extent - fix unexpected file length when appending to a file using direct io and buffer not faulted in - in zoned mode, fix accounting of unusable space when flipping read-only block group back to read-write - fix page locking when COWing an inline range, assertion failure found by syzbot - fix calculation of space info in debugging print - tree-checker, add validation of data reference item - fix a few -Wmaybe-uninitialized build warnings * tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: initialize location to fix -Wmaybe-uninitialized in btrfs_lookup_dentry() btrfs: fix corruption after buffer fault in during direct IO append write btrfs: zoned: fix zone_unusable accounting on making block group read-write again btrfs: do not subtract delalloc from avail bytes btrfs: make cow_file_range_inline() honor locked_page on error btrfs: fix corrupt read due to bad offset of a compressed extent map btrfs: tree-checker: validate dref root and objectid

btrfs: zoned: fix zone_unusable accounting on making block group read-write again

2024-07-29T17:21:19Z

When btrfs makes a block group read-only, it adds all free regions in the block group to space_info->bytes_readonly. That free space excludes reserved and pinned regions. OTOH, when btrfs makes the block group read-write again, it moves all the unused regions into the block group's zone_unusable. That unused region includes reserved and pinned regions. As a result, it counts too much zone_unusable bytes. Fortunately (or unfortunately), having erroneous zone_unusable does not affect the calculation of space_info->bytes_readonly, because free space (num_bytes in btrfs_dec_block_group_ro) calculation is done based on the erroneous zone_unusable and it reduces the num_bytes just to cancel the error. This behavior can be easily discovered by adding a WARN_ON to check e.g, "bg->pinned > 0" in btrfs_dec_block_group_ro(), and running fstests test case like btrfs/282. Fix it by properly considering pinned and reserved in btrfs_dec_block_group_ro(). Also, add a WARN_ON and introduce btrfs_space_info_update_bytes_zone_unusable() to catch a similar mistake. Fixes: 169e0da91a21 ("btrfs: zoned: track unusable bytes for zones") CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Naohiro Aota Reviewed-by: Josef Bacik Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba

Merge tag 'for-6.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2024-07-17T19:38:04Z

Pull btrfs updates from David Sterba: "The highlights are new logic behind background block group reclaim, automatic removal of qgroup after removing a subvolume and new 'rescue=' mount options. The rest is optimizations, cleanups and refactoring. User visible features: - dynamic block group reclaim: - tunable framework to avoid situations where eager data allocations prevent creating new metadata chunks due to lack of unallocated space - reuse sysfs knob bg_reclaim_threshold (otherwise used only in zoned mode) for a fixed value threshold - new on/off sysfs knob "dynamic_reclaim" calculating the value based on heuristics, aiming to keep spare working space for relocating chunks but not to needlessly relocate partially utilized block groups or reclaim newly allocated ones - stats are exported in sysfs per block group type, files "reclaim_*" - this may increase IO load at unexpected times but the corner case of no allocatable block groups is known to be worse - automatically remove qgroup of deleted subvolumes: - adjust qgroup removal conditions, make sure all related subvolume data are already removed, or return EBUSY, also take into account setting of sysfs drop_subtree_threshold - also works in squota mode - mount option updates: new modes of 'rescue=' that allow to mount images (read-only) that could have been partially converted by user space tools - ignoremetacsums - invalid metadata checksums are ignored - ignoresuperflags - super block flags that track conversion in progress (like UUID or checksums) Core: - size of struct btrfs_inode is now below 1024 (on a release config), improved memory packing and other secondary effects - switch tracking of open inodes from rb-tree to xarray, minor performance improvement - reduce number of empty transaction commits when there are no dirty data/metadata - memory allocation optimizations (reduced numbers, reordering out of critical sections) - extent map structure optimizations and refactoring, more sanity checks - more subpage in zoned mode preparations or fixes - general snapshot code cleanups, improvements and documentation - tree-checker updates: more file extent ram_bytes fixes, continued - raid-stripe-tree update (not backward compatible): - remove extent encoding field from the structure, can be inferred from other information - requires btrfs-progs 6.9.1 or newer - cleanups and refactoring - error message updates - error handling improvements - return type and parameter cleanups and improvements" * tag 'for-6.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (152 commits) btrfs: fix extent map use-after-free when adding pages to compressed bio btrfs: fix bitmap leak when loading free space cache on duplicate entry btrfs: remove the BUG_ON() inside extent_range_clear_dirty_for_io() btrfs: move extent_range_clear_dirty_for_io() into inode.c btrfs: enhance compression error messages btrfs: fix data race when accessing the last_trans field of a root btrfs: rename the extra_gfp parameter of btrfs_alloc_page_array() btrfs: remove the extra_gfp parameter from btrfs_alloc_folio_array() btrfs: introduce new "rescue=ignoresuperflags" mount option btrfs: introduce new "rescue=ignoremetacsums" mount option btrfs: output the unrecognized super block flags as hex btrfs: remove unused Opt enums btrfs: tree-checker: add extra ram_bytes and disk_num_bytes check btrfs: fix the ram_bytes assignment for truncated ordered extents btrfs: make validate_extent_map() catch ram_bytes mismatch btrfs: ignore incorrect btrfs_file_extent_item::ram_bytes btrfs: cleanup the bytenr usage inside btrfs_extent_item_to_extent_map() btrfs: fix typo in error message in btrfs_validate_super() btrfs: move the direct IO code into its own file btrfs: pass a btrfs_inode to btrfs_set_prop() ...