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2024-09-27bcachefs: check_subvol_path() now prints subvol root inodeKent Overstreet2-20/+14
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: remove_backpointer() now checks if dirent points to inodeKent Overstreet1-6/+9
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: dirent_points_to_inode() now warns on mismatchKent Overstreet1-28/+56
if an inode backpointer points to a dirent that doesn't point back, that's an error we should warn about. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix lost wake upAlan Huang1-3/+9
If the reader acquires the read lock and then the writer enters the slow path, while the reader proceeds to the unlock path, the following scenario can occur without the change: writer: pcpu_read_count(lock) return 1 (so __do_six_trylock will return 0) reader: this_cpu_dec(*lock->readers) reader: smp_mb() reader: state = atomic_read(&lock->state) (there is no waiting flag set) writer: six_set_bitmask() then the writer will sleep forever. Signed-off-by: Alan Huang <mmpgouride@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Check for logged ops when cleanKent Overstreet2-3/+13
If we shut down successfully, there shouldn't be any logged ops to resume. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: BCH_FS_clean_recoveryKent Overstreet4-3/+8
Add a filesystem flag to indicate whether we did a clean recovery - using c->sb.clean after we've got rw is incorrect, since c->sb is updated whenever we write the superblock. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Convert disk accounting BUG_ON() to WARN_ON()Kent Overstreet1-1/+1
We had a bug where disk accounting keys didn't always have their version field set in journal replay; change the BUG_ON() to a WARN(), and exclude this case since it's now checked for elsewhere (in the bkey validate function). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix BCH_TRANS_COMMIT_skip_accounting_applyKent Overstreet1-16/+20
This was added to avoid double-counting accounting keys in journal replay. But applied incorrectly (easily done since it applies to the transaction commit, not a particular update), it leads to skipping in-mem accounting for real accounting updates, and failure to give them a version number - which leads to journal replay becoming very confused the next time around. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Check for accounting keys with bversion=0Kent Overstreet3-3/+8
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: rename version -> bversionKent Overstreet17-30/+30
give bversions a more distinct name, to aid in grepping Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Don't delete unlinked inodes before logged op resumeKent Overstreet4-21/+36
Previously, check_inode() would delete unlinked inodes if they weren't on the deleted list - this code dating from before there was a deleted list. But, if we crash during a logged op (truncate or finsert/fcollapse) of an unlinked file, logged op resume will get confused if the inode has already been deleted - instead, just add it to the deleted list if it needs to be there; delete_dead_inodes runs after logged op resume. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix BCH_SB_ERRS() so we can reorderKent Overstreet5-8/+9
BCH_SB_ERRS() has a field for the actual enum val so that we can reorder to reorganize, but the way BCH_SB_ERR_MAX was defined didn't allow for this. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix fsck warnings from bkey validationKent Overstreet2-2/+14
__bch2_fsck_err() warns if the current task has a btree_trans object and it wasn't passed in, because if it has to prompt for user input it has to be able to unlock it. But plumbing the btree_trans through bkey_validate(), as well as transaction restarts, is problematic - so instead make bkey fsck errors FSCK_AUTOFIX, which doesn't need to warn. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Move transaction commit path validation to as late as possibleKent Overstreet1-34/+34
In order to check for accounting keys with version=0, we need to run validation after they've been assigned version numbers. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix disk accounting attempting to mark invalid replicas entryKent Overstreet1-3/+18
This fixes the following bug, where a disk accounting key has an invalid replicas entry, and we attempt to add it to the superblock: bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): starting version 1.12: rebalance_work_acct_fix opts=metadata_replicas=2,data_replicas=2,foreground_target=ssd,background_target=hdd,nopromote_whole_extents,verbose,fsck,fix_errors=yes bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): recovering from clean shutdown, journal seq 15211644 bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): accounting_read... accounting not marked in superblock replicas replicas cached: 1/1 [0], fixing bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): sb invalid before write: Invalid superblock section replicas_v0: invalid device 0 in entry cached: 1/1 [0] replicas_v0 (size 88): user: 2 [3 5] user: 2 [1 4] cached: 1 [2] btree: 2 [1 2] user: 2 [2 5] cached: 1 [0] cached: 1 [4] journal: 2 [1 5] user: 2 [1 2] user: 2 [2 3] user: 2 [3 4] user: 2 [4 5] cached: 1 [1] cached: 1 [3] cached: 1 [5] journal: 2 [1 2] journal: 2 [2 5] btree: 2 [2 5] user: 2 [1 3] user: 2 [1 5] user: 2 [2 4] bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): inconsistency detected - emergency read only at journal seq 15211644 accounting not marked in superblock replicas replicas user: 1/1 [3], fixing bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): sb invalid before write: Invalid superblock section replicas_v0: invalid device 0 in entry cached: 1/1 [0] replicas_v0 (size 96): user: 2 [3 5] user: 2 [1 3] cached: 1 [2] btree: 2 [1 2] user: 2 [2 4] cached: 1 [0] cached: 1 [4] journal: 2 [1 5] user: 1 [3] user: 2 [1 5] user: 2 [3 4] user: 2 [4 5] cached: 1 [1] cached: 1 [3] cached: 1 [5] journal: 2 [1 2] journal: 2 [2 5] btree: 2 [2 5] user: 2 [1 2] user: 2 [1 4] user: 2 [2 3] user: 2 [2 5] accounting not marked in superblock replicas replicas user: 1/2 [3 7], fixing bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): sb invalid before write: Invalid superblock section replicas_v0: invalid device 7 in entry user: 1/2 [3 7] replicas_v0 (size 96): user: 2 [3 7] user: 2 [1 3] cached: 1 [2] btree: 2 [1 2] user: 2 [2 4] cached: 1 [0] cached: 1 [4] journal: 2 [1 5] user: 1 [3] user: 2 [1 5] user: 2 [3 4] user: 2 [4 5] cached: 1 [1] cached: 1 [3] cached: 1 [5] journal: 2 [1 2] journal: 2 [2 5] btree: 2 [2 5] user: 2 [1 2] user: 2 [1 4] user: 2 [2 3] user: 2 [2 5] user: 2 [3 5] done bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): alloc_read... done bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): stripes_read... done bcachefs (3c0860e8-07ca-4276-8954-11c1774be868): snapshots_read... done Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix unlocked access to c->disk_sb.sb in bch2_replicas_entry_validate()Kent Overstreet3-6/+16
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix accounting read + device removalKent Overstreet1-18/+29
accounting read was checking if accounting replicas entries were marked in the superblock prior to applying accounting from the journal, which meant that a recently removed device could spuriously trigger a "not marked in superblocked" error (when journal entries zero out the offending counter). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: bch_accounting_modeKent Overstreet3-13/+26
Minor refactoring - replace multiple bool arguments with an enum; prep work for fixing a bug in accounting read. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: fix transaction restart handling in check_extents(), check_dirents()Kent Overstreet1-39/+55
Dealing with outside state within a btree transaction is always tricky. check_extents() and check_dirents() have to accumulate counters for i_sectors and i_nlink (for subdirectories). There were two bugs: - transaction commit may return a restart; therefore we have to commit before accumulating to those counters - get_inode_all_snapshots() may return a transaction restart, before updating w->last_pos; then, on the restart, check_i_sectors()/check_subdir_count() would see inodes that were not for w->last_pos Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: kill inode_walker_entry.seen_this_posKent Overstreet1-6/+0
dead code Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix incorrect IS_ERR_OR_NULL usageKent Overstreet1-1/+1
Returning a positive integer instead of an error code causes error paths to become very confused. Closes: syzbot+c0360e8367d6d8d04a66@syzkaller.appspotmail.com Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: fix the memory leak in exception caseHongbo Li1-0/+1
The pointer clean points the memory allocated by kmemdup, when the return value of bch2_sb_clean_validate_late is not zero. The memory pointed by clean is leaked. So we should free it in this case. Fixes: a37ad1a3aba9 ("bcachefs: sb-clean.c") Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: fast exit when darray_make_room failedHongbo Li1-1/+3
In downgrade_table_extra, the return value is needed. When it return failed, we should exit immediately. Fixes: 7773df19c35f ("bcachefs: metadata version bucket_stripe_sectors") Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix iterator leak in check_subvol()Kent Overstreet1-28/+26
A couple small error handling fixes Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Add snapshot to bch_inode_unpackedKent Overstreet2-4/+7
this allows for various cleanups in fsck Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: assign return error when iterating through layoutDiogo Jahchan Koike1-1/+3
syzbot reported a null ptr deref in __copy_user [0] In __bch2_read_super, when a corrupt backup superblock matches the default opts offset, no error is assigned to ret and the freed superblock gets through, possibly being assigned as the best sb in bch2_fs_open and being later dereferenced, causing a fault. Assign EINVALID to ret when iterating through layout. [0]: https://syzkaller.appspot.com/bug?extid=18a5c5e8a9c856944876 Reported-by: syzbot+18a5c5e8a9c856944876@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=18a5c5e8a9c856944876 Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix srcu warning in check_topologyKent Overstreet1-0/+2
check_topology doesn't need the srcu lock and doesn't use normal btree transactions - we can just drop the srcu lock. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Fix error path in check_dirent_inode_dirent()Kent Overstreet1-3/+2
fsck_err() jumps to the fsck_err label when bailing out; need to make sure bp_iter was initialized... Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: memset bounce buffer portion to 0 after key_sort_fix_overlappingPiotr Zalewski1-0/+4
Zero-initialize part of allocated bounce buffer which wasn't touched by subsequent bch2_key_sort_fix_overlapping to mitigate later uinit-value use KMSAN bug[1]. After applying the patch reproducer still triggers stack overflow[2] but it seems unrelated to the uninit-value use warning. After further investigation it was found that stack overflow occurs because KMSAN adds too many function calls[3]. Backtrace of where the stack magic number gets smashed was added as a reply to syzkaller thread[3]. It was confirmed that task's stack magic number gets smashed after the code path where KSMAN detects uninit-value use is executed, so it can be assumed that it doesn't contribute in any way to uninit-value use detection. [1] https://syzkaller.appspot.com/bug?extid=6f655a60d3244d0c6718 [2] https://lore.kernel.org/lkml/66e57e46.050a0220.115905.0002.GAE@google.com [3] https://lore.kernel.org/all/rVaWgPULej8K7HqMPNIu8kVNyXNjjCiTB-QBtItLFBmk0alH6fV2tk4joVPk97Evnuv4ZRDd8HB5uDCkiFG6u81xKdzDj-KrtIMJSlF6Kt8=@proton.me Reported-by: syzbot+6f655a60d3244d0c6718@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6f655a60d3244d0c6718 Fixes: ec4edd7b9d20 ("bcachefs: Prep work for variable size btree node buffers") Suggested-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Piotr Zalewski <pZ010001011111@proton.me> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Improve bch2_is_inode_open() warning messageKent Overstreet1-3/+3
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Add extra padding in bkey_make_mut_noupdate()Kent Overstreet1-1/+2
This fixes a kasan splat in propagate_key_to_snapshot_leaves() - varint_decode_fast() does reads (that it never uses) up to 7 bytes past the end of the integer. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27bcachefs: Mark inode errors as autofixKent Overstreet1-16/+16
Most or all errors will be autofix in the future, we're currently just doing the ones that we know are well tested. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-27[tree-wide] finally take no_llseek outAl Viro2-3/+0
no_llseek had been defined to NULL two years ago, in commit 868941b14441 ("fs: remove no_llseek") To quote that commit, At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\<no_llseek\>/d' $i done would do it. Unfortunately, that hadn't been done. Linus, could you do that now, so that we could finally put that thing to rest? All instances are of the form .llseek = no_llseek, so it's obviously safe. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-09-23bcachefs: Fix infinite loop in propagate_key_to_snapshot_leaves()Kent Overstreet1-0/+1
As we iterate we need to mark that we no longer need iterators - otherwise we'll infinite loop via the "too many iters" check when there's many snapshots. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-23bcachefs: Ensure BCH_FS_accounting_replay_done is always setKent Overstreet1-0/+3
if it doesn't get set we'll never be able to flush the btree write buffer; this only happens in fake rw mode, but prevents us from shutting down. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-23Merge tag 'bcachefs-2024-09-21' of git://evilpiepirate.org/bcachefsLinus Torvalds84-1604/+3037
Pull bcachefs updates from Kent Overstreet: - rcu_pending, btree key cache rework: this solves lock contenting in the key cache, eliminating the biggest source of the srcu lock hold time warnings, and drastically improving performance on some metadata heavy workloads - on multithreaded creates we're now 3-4x faster than xfs. - We're now using an rhashtable instead of the system inode hash table; this is another significant performance improvement on multithreaded metadata workloads, eliminating more lock contention. - for_each_btree_key_in_subvolume_upto(): new helper for iterating over keys within a specific subvolume, eliminating a lot of open coded "subvolume_get_snapshot()" and also fixing another source of srcu lock time warnings, by running each loop iteration in its own transaction (as the existing for_each_btree_key() does). - More work on btree_trans locking asserts; we now assert that we don't hold btree node locks when trans->locked is false, which is important because we don't use lockdep for tracking individual btree node locks. - Some cleanups and improvements in the bset.c btree node lookup code, from Alan. - Rework of btree node pinning, which we use in backpointers fsck. The old hacky implementation, where the shrinker just skipped over nodes in the pinned range, was causing OOMs; instead we now use another shrinker with a much higher seeks number for pinned nodes. - Rebalance now uses BCH_WRITE_ONLY_SPECIFIED_DEVS; this fixes an issue where rebalance would sometimes fall back to allocating from the full filesystem, which is not what we want when it's trying to move data to a specific target. - Use __GFP_ACCOUNT, GFP_RECLAIMABLE for btree node, key cache allocations. - Idmap mounts are now supported (Hongbo Li) - Rename whiteouts are now supported (Hongbo Li) - Erasure coding can now handle devices being marked as failed, or forcibly removed. We still need the evacuate path for erasure coding, but it's getting very close to ready for people to start using. * tag 'bcachefs-2024-09-21' of git://evilpiepirate.org/bcachefs: (99 commits) bcachefs: return err ptr instead of null in read sb clean bcachefs: Remove duplicated include in backpointers.c bcachefs: Don't drop devices with stripe pointers bcachefs: bch2_ec_stripe_head_get() now checks for change in rw devices bcachefs: bch_fs.rw_devs_change_count bcachefs: bch2_dev_remove_stripes() bcachefs: bch2_trigger_ptr() calculates sectors even when no device bcachefs: improve error messages in bch2_ec_read_extent() bcachefs: improve error message on too few devices for ec bcachefs: improve bch2_new_stripe_to_text() bcachefs: ec_stripe_head.nr_created bcachefs: bch_stripe.disk_label bcachefs: stripe_to_mem() bcachefs: EIO errcode cleanup bcachefs: Rework btree node pinning bcachefs: split up btree cache counters for live, freeable bcachefs: btree cache counters should be size_t bcachefs: Don't count "skipped access bit" as touched in btree cache scan bcachefs: Failed devices no longer require mounting in degraded mode bcachefs: bch2_dev_rcu_noerror() ...
2024-09-21bcachefs: Hold read lock in bch2_snapshot_tree_oldest_subvol()Ahmed Ehab1-0/+2
Syzbot reports a problem that a warning is triggered due to suspicious use of rcu_dereference_check(). That is triggered by a call of bch2_snapshot_tree_oldest_subvol(). The cause of the warning is that inside bch2_snapshot_tree_oldest_subvol(), snapshot_t() is called which calls rcu_dereference() that requires a read lock to be held. Also, the call of bch2_snapshot_tree_next() eventually calls snapshot_t(). To fix this, call rcu_read_lock() before calling snapshot_t(). Then, release the lock after the termination of the while loop. Reported-by: <syzbot+f7c41a878676b72c16a6@syzkaller.appspotmail.com> Signed-off-by: Ahmed Ehab <bottaawesome633@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: return err ptr instead of null in read sb cleanDiogo Jahchan Koike1-1/+1
syzbot reported a null-ptr-deref in bch2_fs_start. [0] When a sb is marked clear but doesn't have a clean section bch2_read_superblock_clean returns NULL which PTR_ERR_OR_ZERO lets through, eventually leading to a null ptr dereference down the line. Adjust read sb clean to return an ERR_PTR indicating the invalid clean section. [0] https://syzkaller.appspot.com/bug?extid=1cecc37d87c4286e5543 Reported-by: syzbot+1cecc37d87c4286e5543@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1cecc37d87c4286e5543 Signed-off-by: Diogo Jahchan Koike <djahchankoike@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: Remove duplicated include in backpointers.cYang Li1-1/+0
The header files bbpos.h is included twice in backpointers.c, so one inclusion of each can be removed. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=10783 Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: Don't drop devices with stripe pointersKent Overstreet4-9/+32
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: bch2_ec_stripe_head_get() now checks for change in rw devicesKent Overstreet2-27/+60
This factors out ec_strie_head_devs_update(), which initializes the bitmap of devices we're allocating from, and runs it every time c->rw_devs_change_count changes. We also cancel pending, not allocated stripes, since they may refer to devices that are no longer available. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: bch_fs.rw_devs_change_countKent Overstreet2-4/+9
Add a counter that's incremented whenever rw devices change; this will be used for erasure coding so that it can keep ec_stripe_head in sync and not deadlock on a new stripe when a device it wants goes away. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: bch2_dev_remove_stripes()Kent Overstreet4-3/+74
We can now correctly force-remove a device that has stripes on it; this uses the new BCH_SB_MEMBER_INVALID sentinal value. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: bch2_trigger_ptr() calculates sectors even when no deviceKent Overstreet2-10/+21
This is necessary for erasure coded pointers to devices that have been removed. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: improve error messages in bch2_ec_read_extent()Kent Overstreet3-19/+23
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: improve error message on too few devices for ecKent Overstreet1-3/+16
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: improve bch2_new_stripe_to_text()Kent Overstreet1-0/+2
also print out the new stripe key Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: ec_stripe_head.nr_createdKent Overstreet2-2/+6
additional debug stat Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: bch_stripe.disk_labelKent Overstreet4-16/+43
When reshaping existing stripes, we should keep them on the same target that they were allocated on; to do this, we need to add a field to the btree stripe type. This is a tad awkward, because we only have 8 bits left, and targets are 16 bits - but we only need to store a label, not a full target. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-09-21bcachefs: stripe_to_mem()Kent Overstreet1-18/+15
factor out a common helper Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>