- 10 Aug, 2023 6 commits
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Qu Wenruo authored
[BUG] Syzbot reported a crash that an ASSERT() got triggered inside prepare_to_merge(). [CAUSE] The root cause of the triggered ASSERT() is we can have a race between quota tree creation and relocation. This leads us to create a duplicated quota tree in the btrfs_read_fs_root() path, and since it's treated as fs tree, it would have ROOT_SHAREABLE flag, causing us to create a reloc tree for it. The bug itself is fixed by a dedicated patch for it, but this already taught us the ASSERT() is not something straightforward for developers. [ENHANCEMENT] Instead of using an ASSERT(), let's handle it gracefully and output extra info about the mismatch reloc roots to help debug. Also with the above ASSERT() removed, we can trigger ASSERT(0)s inside merge_reloc_roots() later. Also replace those ASSERT(0)s with WARN_ON()s. CC: stable@vger.kernel.org # 5.15+ Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com Reviewed-by:
Filipe Manana <fdmanana@suse.com> Signed-off-by:
Qu Wenruo <wqu@suse.com> Signed-off-by:
David Sterba <dsterba@suse.com>
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Qu Wenruo authored
[BUG] Syzbot reported a weird ASSERT() triggered inside prepare_to_merge(). assertion failed: root->reloc_root == reloc_root, in fs/btrfs/relocation.c:1919 ------------[ cut here ]------------ kernel BUG at fs/btrfs/relocation.c:1919! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 9904 Comm: syz-executor.3 Not tainted 6.4.0-syzkaller-08881-g533925cb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 RIP: 0010:prepare_to_merge+0xbb2/0xc40 fs/btrfs/relocation.c:1919 Code: fe e9 f5 (...) RSP: 0018:ffffc9000325f760 EFLAGS: 00010246 RAX: 000000000000004f RBX: ffff888075644030 RCX: 1481ccc522da5800 RDX: ffffc90005c09000 RSI: 00000000000364ca RDI: 00000000000364cb RBP: ffffc9000325f870 R08: ffffffff816f33ac R09: 1ffff9200064bea0 R10: dffffc0000000000 R11: fffff5200064bea1 R12: ffff888075644000 R13: ffff88803b166000 R14: ffff88803b166560 R15: ffff88803b166558 FS: 00007f4e305fd700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056080679c000 CR3: 00000000193ad000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> relocate_block_group+0xa5d/0xcd0 fs/btrfs/relocation.c:3749 btrfs_relocate_block_group+0x7ab/0xd70 fs/btrfs/relocation.c:4087 btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3283 __btrfs_balance+0x1b06/0x2690 fs/btrfs/volumes.c:4018 btrfs_balance+0xbdb/0x1120 fs/btrfs/volumes.c:4402 btrfs_ioctl_balance+0x496/0x7c0 fs/btrfs/ioctl.c:3604 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f4e2f88c389 [CAUSE] With extra debugging, the offending reloc_root is for quota tree (rootid 8). Normally we should not use the reloc tree for quota root at all, as reloc trees are only for subvolume trees. But there is a race between quota enabling and relocation, this happens after commit 85724171 ("btrfs: fix the btrfs_get_global_root return value"). Before that commit, for quota and free space tree, we exit immediately if we cannot grab it from fs_info. But now we would try to read it from disk, just as if they are fs trees, this sets ROOT_SHAREABLE flags in such race: Thread A | Thread B ---------------------------------+------------------------------ btrfs_quota_enable() | | | btrfs_get_root_ref() | | |- btrfs_get_global_root() | | | Returned NULL | | |- btrfs_lookup_fs_root() | | | Returned NULL |- btrfs_create_tree() | | | Now quota root item is | | | inserted | |- btrfs_read_tree_root() | | | Got the newly inserted quota root | | |- btrfs_init_fs_root() | | | Set ROOT_SHAREABLE flag [FIX] Get back to the old behavior by returning PTR_ERR(-ENOENT) if the target objectid is not a subvolume tree or data reloc tree. Reported-and-tested-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com Fixes: 85724171 ("btrfs: fix the btrfs_get_global_root return value") Reviewed-by:
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Christoph Hellwig authored
When the call to btrfs_reloc_clone_csums in cow_file_range returns an error, we jump to the out_unlock label with the extent_reserved variable set to false. The cleanup at the label will then call extent_clear_unlock_delalloc on the range from start to end. But we've already added cur_alloc_size to start before the jump, so there might no range be left from the newly incremented start to end. Move the check for 'start < end' so that it is reached by also for the !extent_reserved case. CC: stable@vger.kernel.org # 6.1+ Fixes: a315e68f ("Btrfs: fix invalid attempt to free reserved space on failure to cow range") Reviewed-by:
Josef Bacik <josef@toxicpanda.com> Signed-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
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Christoph Hellwig authored
__extent_writepage could have started on more pages than the one it was called for. This happens regularly for zoned file systems, and in theory could happen for compressed I/O if the worker thread was executed very quickly. For such pages extent_write_cache_pages waits for writeback to complete before moving on to the next page, which is highly inefficient as it blocks the flusher thread. Port over the PageDirty check that was added to write_cache_pages in commit 515f4a03 ("mm: write_cache_pages optimise page cleaning") to fix this. CC: stable@vger.kernel.org # 4.14+ Reviewed-by:
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Christoph Hellwig authored
extent_write_cache_pages stops writing pages as soon as nr_to_write hits zero. That is the right thing for opportunistic writeback, but incorrect for data integrity writeback, which needs to ensure that no dirty pages are left in the range. Thus only stop the writeback for WB_SYNC_NONE if nr_to_write hits 0. This is a port of write_cache_pages changes in commit 05fe478d ("mm: write_cache_pages integrity fix"). Note that I've only trigger the problem with other changes to the btrfs writeback code, but this condition seems worthwhile fixing anyway. CC: stable@vger.kernel.org # 4.14+ Reviewed-by:
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Josef Bacik authored
Recently we've been having mysterious hangs while running generic/475 on the CI system. This turned out to be something like this: Task 1 dmsetup suspend --nolockfs -> __dm_suspend -> dm_wait_for_completion -> dm_wait_for_bios_completion -> Unable to complete because of IO's on a plug in Task 2 Task 2 wb_workfn -> wb_writeback -> blk_start_plug -> writeback_sb_inodes -> Infinite loop unable to make an allocation Task 3 cache_block_group ->read_extent_buffer_pages ->Waiting for IO to complete that can't be submitted because Task 1 suspended the DM device The problem here is that we need Task 2 to be scheduled completely for the blk plug to flush. Normally this would happen, we normally wait for the block group caching to finish (Task 3), and this schedule would result in the block plug flushing. However if there's enough free space available from the current caching to satisfy the allocation we won't actually wait for the caching to complete. This check however just checks that we have enough space, not that we can make the allocation. In this particular case we were trying to allocate 9MiB, and we had 10MiB of free space, but we didn't have 9MiB of contiguous space to allocate, and thus the allocation failed and we looped. We specifically don't cycle through the FFE loop until we stop finding cached block groups because we don't want to allocate new block groups just because we're caching, so we short circuit the normal loop once we hit LOOP_CACHING_WAIT and we found a caching block group. This is normally fine, except in this particular case where the caching thread can't make progress because the DM device has been suspended. Fix this by not only waiting for free space to >= the amount of space we want to allocate, but also that we make some progress in caching from the time we start waiting. This will keep us from busy looping when the caching is taking a while but still theoretically has enough space for us to allocate from, and fixes this particular case by forcing us to actually sleep and wait for forward progress, which will flush the plug. With this fix we're no longer hanging with generic/475. CC: stable@vger.kernel.org # 6.1+ Reviewed-by:Boris Burkov <boris@bur.io> Signed-off-by:
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- 26 Jul, 2023 1 commit
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Filipe Manana authored
btrfs_attach_transaction_barrier() is used to get a handle pointing to the current running transaction if the transaction has not started its commit yet (its state is < TRANS_STATE_COMMIT_START). If the transaction commit has started, then we wait for the transaction to commit and finish before returning - however we completely ignore if the transaction was aborted due to some error during its commit, we simply return ERR_PT(-ENOENT), which makes the caller assume everything is fine and no errors happened. This could make an fsync return success (0) to user space when in fact we had a transaction abort and the target inode changes were therefore not persisted. Fix this by checking for the return value from btrfs_wait_for_commit(), and if it returned an error, return it back to the caller. Fixes: d4edf39b ("Btrfs: fix uncompleted transaction") CC: stable@vger.kernel.org # 4.19+ Reviewed-by:
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- 24 Jul, 2023 2 commits
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Filipe Manana authored
At btrfs_wait_for_commit() we wait for a transaction to finish and then always return 0 (success) without checking if it was aborted, in which case the transaction didn't happen due to some critical error. Fix this by checking if the transaction was aborted. Fixes: 46204592 ("Btrfs: add START_SYNC, WAIT_SYNC ioctls") CC: stable@vger.kernel.org # 4.19+ Reviewed-by:
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Filipe Manana authored
At add_new_free_space() we have these BUG_ON()'s that are there to deal with any failure to add free space to the in memory free space cache. Such failures are mostly -ENOMEM that should be very rare. However there's no need to have these BUG_ON()'s, we can just return any error to the caller and all callers and their upper call chain are already dealing with errors. So just make add_new_free_space() return any errors, while removing the BUG_ON()'s, and returning the total amount of added free space to an optional u64 pointer argument. Reported-by: syzbot+3ba856e07b7127889d8c@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/000000000000e9cb8305ff4e8327@google.com/Signed-off-by:
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- 20 Jul, 2023 2 commits
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Filipe Manana authored
When using the block group tree feature, this tree is a critical tree just like the extent, csum and free space trees, and just like them it uses the delayed refs block reserve. So take into account the block group tree, and its current size, when calculating the size for the global reserve. CC: stable@vger.kernel.org # 6.1+ Signed-off-by:
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Naohiro Aota authored
The zoned mode need to reset a zone before using it. We rely on btrfs's original discard functionality (discarding unused block group range) to do the resetting. While the commit 63a7cb13 ("btrfs: auto enable discard=async when possible") made the discard done in an async manner, a zoned reset do not need to be async, as it is fast enough. Even worth, delaying zone rests prevents using those zones again. So, let's disable async discard on the zoned mode. Fixes: 63a7cb13 ("btrfs: auto enable discard=async when possible") CC: stable@vger.kernel.org # 6.3+ Reviewed-by:
Damien Le Moal <dlemoal@kernel.org> Reviewed-by:
Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by:
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- 18 Jul, 2023 8 commits
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Filipe Manana authored
If we have a transaction abort with qgroups enabled we get a warning triggered when doing the final put on the transaction, like this: [552.6789] ------------[ cut here ]------------ [552.6815] WARNING: CPU: 4 PID: 81745 at fs/btrfs/transaction.c:144 btrfs_put_transaction+0x123/0x130 [btrfs] [552.6817] Modules linked in: btrfs blake2b_generic xor (...) [552.6819] CPU: 4 PID: 81745 Comm: btrfs-transacti Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1 [552.6819] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [552.6819] RIP: 0010:btrfs_put_transaction+0x123/0x130 [btrfs] [552.6821] Code: bd a0 01 00 (...) [552.6821] RSP: 0018:ffffa168c0527e28 EFLAGS: 00010286 [552.6821] RAX: ffff936042caed00 RBX: ffff93604a3eb448 RCX: 0000000000000000 [552.6821] RDX: ffff93606421b028 RSI: ffffffff92ff0878 RDI: ffff93606421b010 [552.6821] RBP: ffff93606421b000 R08: 0000000000000000 R09: ffffa168c0d07c20 [552.6821] R10: 0000000000000000 R11: ffff93608dc52950 R12: ffffa168c0527e70 [552.6821] R13: ffff93606421b000 R14: ffff93604a3eb420 R15: ffff93606421b028 [552.6821] FS: 0000000000000000(0000) GS:ffff93675fb00000(0000) knlGS:0000000000000000 [552.6821] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [552.6821] CR2: 0000558ad262b000 CR3: 000000014feda005 CR4: 0000000000370ee0 [552.6822] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [552.6822] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [552.6822] Call Trace: [552.6822] <TASK> [552.6822] ? __warn+0x80/0x130 [552.6822] ? btrfs_put_transaction+0x123/0x130 [btrfs] [552.6824] ? report_bug+0x1f4/0x200 [552.6824] ? handle_bug+0x42/0x70 [552.6824] ? exc_invalid_op+0x14/0x70 [552.6824] ? asm_exc_invalid_op+0x16/0x20 [552.6824] ? btrfs_put_transaction+0x123/0x130 [btrfs] [552.6826] btrfs_cleanup_transaction+0xe7/0x5e0 [btrfs] [552.6828] ? _raw_spin_unlock_irqrestore+0x23/0x40 [552.6828] ? try_to_wake_up+0x94/0x5e0 [552.6828] ? __pfx_process_timeout+0x10/0x10 [552.6828] transaction_kthread+0x103/0x1d0 [btrfs] [552.6830] ? __pfx_transaction_kthread+0x10/0x10 [btrfs] [552.6832] kthread+0xee/0x120 [552.6832] ? __pfx_kthread+0x10/0x10 [552.6832] ret_from_fork+0x29/0x50 [552.6832] </TASK> [552.6832] ---[ end trace 0000000000000000 ]--- This corresponds to this line of code: void btrfs_put_transaction(struct btrfs_transaction *transaction) { (...) WARN_ON(!RB_EMPTY_ROOT( &transaction->delayed_refs.dirty_extent_root)); (...) } The warning happens because btrfs_qgroup_destroy_extent_records(), called in the transaction abort path, we free all entries from the rbtree "dirty_extent_root" with rbtree_postorder_for_each_entry_safe(), but we don't actually empty the rbtree - it's still pointing to nodes that were freed. So set the rbtree's root node to NULL to avoid this warning (assign RB_ROOT). Fixes: 81f7eb00 ("btrfs: destroy qgroup extent records on transaction abort") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: -
Christoph Hellwig authored
When the call to btrfs_extract_ordered_extent in btrfs_dio_submit_io fails to allocate memory for a new ordered_extent, it calls into the btrfs_dio_end_io for error handling. btrfs_dio_end_io then assumes that bbio->ordered is set because it is supposed to be at this point, except for this error handling corner case. Try to not overload the btrfs_dio_end_io with error handling of a bio in a non-canonical state, and instead call btrfs_finish_ordered_extent and iomap_dio_bio_end_io directly for this error case. Reported-by:
syzbot <syzbot+5b82f0e951f8c2bcdb8f@syzkaller.appspotmail.com> Fixes: b41b6f69 ("btrfs: use btrfs_finish_ordered_extent to complete direct writes") Reviewed-by:
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Josef Bacik authored
While trying to get the subpage blocksize tests running, I hit the following panic on generic/476 assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229 kernel BUG at fs/btrfs/subpage.c:229! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12 Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023 pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : btrfs_subpage_assert+0xbc/0xf0 lr : btrfs_subpage_assert+0xbc/0xf0 Call trace: btrfs_subpage_assert+0xbc/0xf0 btrfs_subpage_clear_checked+0x38/0xc0 btrfs_page_clear_checked+0x48/0x98 btrfs_truncate_block+0x5d0/0x6a8 btrfs_cont_expand+0x5c/0x528 btrfs_write_check.isra.0+0xf8/0x150 btrfs_buffered_write+0xb4/0x760 btrfs_do_write_iter+0x2f8/0x4b0 btrfs_file_write_iter+0x1c/0x30 do_iter_readv_writev+0xc8/0x158 do_iter_write+0x9c/0x210 vfs_iter_write+0x24/0x40 iter_file_splice_write+0x224/0x390 direct_splice_actor+0x38/0x68 splice_direct_to_actor+0x12c/0x260 do_splice_direct+0x90/0xe8 generic_copy_file_range+0x50/0x90 vfs_copy_file_range+0x29c/0x470 __arm64_sys_copy_file_range+0xcc/0x498 invoke_syscall.constprop.0+0x80/0xd8 do_el0_svc+0x6c/0x168 el0_svc+0x50/0x1b0 el0t_64_sync_handler+0x114/0x120 el0t_64_sync+0x194/0x198 This happens because during btrfs_cont_expand we'll get a page, set it as mapped, and if it's not Uptodate we'll read it. However between the read and re-locking the page we could have called release_folio() on the page, but left the page in the file mapping. release_folio() can clear the page private, and thus further down we blow up when we go to modify the subpage bits. Fix this by putting the set_page_extent_mapped() after the read. This is safe because read_folio() will call set_page_extent_mapped() before it does the read, and then if we clear page private but leave it on the mapping we're completely safe re-setting set_page_extent_mapped(). With this patch I can now run generic/476 without panicing. CC: stable@vger.kernel.org # 6.1+ Reviewed-by:
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Qu Wenruo authored
[REGRESSION] Commit 75b47033 ("btrfs: raid56: migrate recovery and scrub recovery path to use error_bitmap") changed the behavior of scrub_rbio(). Initially if we have no error reading the raid bio, we will assign @need_check to true, then finish_parity_scrub() would later verify the content of P/Q stripes before writeback. But after that commit we never verify the content of P/Q stripes and just writeback them. This can lead to unrepaired P/Q stripes during scrub, or already corrupted P/Q copied to the dev-replace target. [FIX] The situation is more complex than the regression, in fact the initial behavior is not 100% correct either. If we have the following rare case, it can still lead to the same problem using the old behavior: 0 16K 32K 48K 64K Data 1: |IIIIIII| | Data 2: | | Parity: | |CCCCCCC| | Where "I" means IO error, "C" means corruption. In the above case, we're scrubbing the parity stripe, then read out all the contents of Data 1, Data 2, Parity stripes. But found IO error in Data 1, which leads to rebuild using Data 2 and Parity and got the correct data. In that case, we would not verify if the Parity is correct for range [16K, 32K). So here we have to always verify the content of Parity no matter if we did recovery or not. This patch would remove the @need_check parameter of finish_parity_scrub() completely, and would always do the P/Q verification before writeback. Fixes: 75b47033 ("btrfs: raid56: migrate recovery and scrub recovery path to use error_bitmap") CC: stable@vger.kernel.org # 6.2+ Signed-off-by:
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Filipe Manana authored
Running delayed iputs, which never happens in an irq context, needs to lock the spinlock fs_info->delayed_iput_lock. When finishing bios for data writes (irq context, bio.c) we call btrfs_put_ordered_extent() which needs to add a delayed iput and for that it needs to acquire the spinlock fs_info->delayed_iput_lock. Without disabling irqs when running delayed iputs we can therefore deadlock on that spinlock. The same deadlock can also happen when adding an inode to the delayed iputs list, since this can be done outside an irq context as well. Syzbot recently reported this, which results in the following trace: ================================ WARNING: inconsistent lock state 6.4.0-syzkaller-09904-ga507db1d #0 Not tainted -------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. btrfs-cleaner/16079 [HC0[0]:SC0[0]:HE1:SE1] takes: ffff888107804d20 (&fs_info->delayed_iput_lock){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] ffff888107804d20 (&fs_info->delayed_iput_lock){+.?.}-{2:2}, at: btrfs_run_delayed_iputs+0x28/0xe0 fs/btrfs/inode.c:3523 {IN-SOFTIRQ-W} state was registered at: lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5726 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] btrfs_add_delayed_iput+0x128/0x390 fs/btrfs/inode.c:3490 btrfs_put_ordered_extent fs/btrfs/ordered-data.c:559 [inline] btrfs_put_ordered_extent+0x2f6/0x610 fs/btrfs/ordered-data.c:547 __btrfs_bio_end_io fs/btrfs/bio.c:118 [inline] __btrfs_bio_end_io+0x136/0x180 fs/btrfs/bio.c:112 btrfs_orig_bbio_end_io+0x86/0x2b0 fs/btrfs/bio.c:163 btrfs_simple_end_io+0x105/0x380 fs/btrfs/bio.c:378 bio_endio+0x589/0x690 block/bio.c:1617 req_bio_endio block/blk-mq.c:766 [inline] blk_update_request+0x5c5/0x1620 block/blk-mq.c:911 blk_mq_end_request+0x59/0x680 block/blk-mq.c:1032 lo_complete_rq+0x1c6/0x280 drivers/block/loop.c:370 blk_complete_reqs+0xb3/0xf0 block/blk-mq.c:1110 __do_softirq+0x1d4/0x905 kernel/softirq.c:553 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x659/0x9e0 kernel/smpboot.c:164 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 irq event stamp: 39 hardirqs last enabled at (39): [<ffffffff81d5ebc4>] __do_kmem_cache_free mm/slab.c:3558 [inline] hardirqs last enabled at (39): [<ffffffff81d5ebc4>] kmem_cache_free mm/slab.c:3582 [inline] hardirqs last enabled at (39): [<ffffffff81d5ebc4>] kmem_cache_free+0x244/0x370 mm/slab.c:3575 hardirqs last disabled at (38): [<ffffffff81d5eb5e>] __do_kmem_cache_free mm/slab.c:3553 [inline] hardirqs last disabled at (38): [<ffffffff81d5eb5e>] kmem_cache_free mm/slab.c:3582 [inline] hardirqs last disabled at (38): [<ffffffff81d5eb5e>] kmem_cache_free+0x1de/0x370 mm/slab.c:3575 softirqs last enabled at (0): [<ffffffff814ac99f>] copy_process+0x227f/0x75c0 kernel/fork.c:2448 softirqs last disabled at (0): [<0000000000000000>] 0x0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&fs_info->delayed_iput_lock); <Interrupt> lock(&fs_info->delayed_iput_lock); *** DEADLOCK *** 1 lock held by btrfs-cleaner/16079: #0: ffff888107804860 (&fs_info->cleaner_mutex){+.+.}-{3:3}, at: cleaner_kthread+0x103/0x4b0 fs/btrfs/disk-io.c:1463 stack backtrace: CPU: 3 PID: 16079 Comm: btrfs-cleaner Not tainted 6.4.0-syzkaller-09904-ga507db1d #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:3978 [inline] valid_state kernel/locking/lockdep.c:4020 [inline] mark_lock_irq kernel/locking/lockdep.c:4223 [inline] mark_lock.part.0+0x1102/0x1960 kernel/locking/lockdep.c:4685 mark_lock kernel/locking/lockdep.c:4649 [inline] mark_usage kernel/locking/lockdep.c:4598 [inline] __lock_acquire+0x8e4/0x5e20 kernel/locking/lockdep.c:5098 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5726 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:350 [inline] btrfs_run_delayed_iputs+0x28/0xe0 fs/btrfs/inode.c:3523 cleaner_kthread+0x2e5/0x4b0 fs/btrfs/disk-io.c:1478 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> So fix this by using spin_lock_irq() and spin_unlock_irq() when running delayed iputs, and using spin_lock_irqsave() and spin_unlock_irqrestore() when adding a delayed iput(). Reported-by: syzbot+da501a04be5ff533b102@syzkaller.appspotmail.com Fixes: ec63b84d ("btrfs: add an ordered_extent pointer to struct btrfs_bio") Link: https://lore.kernel.org/linux-btrfs/000000000000d5c89a05ffbd39dd@google.com/Signed-off-by:
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Filipe Manana authored
At btrfs_orphan_cleanup(), if we can't find an inode (btrfs_iget() returns an -ENOENT error pointer), we proceed with 'ret' set to -ENOENT and the inode pointer set to ERR_PTR(-ENOENT). Later when we proceed to the body of the following if statement: if (ret == -ENOENT || inode->i_nlink) { (...) trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); iput(inode); goto out; } (...) ret = btrfs_del_orphan_item(trans, root, found_key.objectid); btrfs_end_transaction(trans); if (ret) { iput(inode); goto out; } continue; } If we get an error from btrfs_start_transaction() or from the call to btrfs_del_orphan_item() we end calling iput() against an inode pointer that has a value of ERR_PTR(-ENOENT), resulting in a crash with the following trace: [876.667] BUG: kernel NULL pointer dereference, address: 0000000000000096 [876.667] #PF: supervisor read access in kernel mode [876.667] #PF: error_code(0x0000) - not-present page [876.667] PGD 0 P4D 0 [876.668] Oops: 0000 [#1] PREEMPT SMP PTI [876.668] CPU: 0 PID: 2356187 Comm: mount Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1 [876.668] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [876.668] RIP: 0010:iput+0xa/0x20 [876.668] Code: ff ff ff 66 (...) [876.669] RSP: 0018:ffffafa9c0c9f9d0 EFLAGS: 00010282 [876.669] RAX: ffffffffffffffe4 RBX: 000000000009453b RCX: 0000000000000000 [876.669] RDX: 0000000000000001 RSI: ffffafa9c0c9f930 RDI: fffffffffffffffe [876.669] RBP: ffff95c612f3b800 R08: 0000000000000001 R09: ffffffffffffffe4 [876.670] R10: 00018f2a71010000 R11: 000000000ead96e3 R12: ffff95cb7d6909a0 [876.670] R13: fffffffffffffffe R14: ffff95c60f477000 R15: 00000000ffffffe4 [876.670] FS: 00007f5fbe30a840(0000) GS:ffff95ccdfa00000(0000) knlGS:0000000000000000 [876.670] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [876.671] CR2: 0000000000000096 CR3: 000000055e9f6004 CR4: 0000000000370ef0 [876.671] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [876.671] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [876.672] Call Trace: [876.744] <TASK> [876.744] ? __die_body+0x1b/0x60 [876.744] ? page_fault_oops+0x15d/0x450 [876.745] ? __kmem_cache_alloc_node+0x47/0x410 [876.745] ? do_user_addr_fault+0x65/0x8a0 [876.745] ? exc_page_fault+0x74/0x170 [876.746] ? asm_exc_page_fault+0x22/0x30 [876.746] ? iput+0xa/0x20 [876.746] btrfs_orphan_cleanup+0x221/0x330 [btrfs] [876.746] btrfs_lookup_dentry+0x58f/0x5f0 [btrfs] [876.747] btrfs_lookup+0xe/0x30 [btrfs] [876.747] __lookup_slow+0x82/0x130 [876.785] walk_component+0xe5/0x160 [876.786] path_lookupat.isra.0+0x6e/0x150 [876.786] filename_lookup+0xcf/0x1a0 [876.786] ? mod_objcg_state+0xd2/0x360 [876.786] ? obj_cgroup_charge+0xf5/0x110 [876.787] ? should_failslab+0xa/0x20 [876.787] ? kmem_cache_alloc+0x47/0x450 [876.787] vfs_path_lookup+0x51/0x90 [876.788] mount_subtree+0x8d/0x130 [876.788] btrfs_mount+0x149/0x410 [btrfs] [876.788] ? __kmem_cache_alloc_node+0x47/0x410 [876.788] ? vfs_parse_fs_param+0xc0/0x110 [876.789] legacy_get_tree+0x24/0x50 [876.834] vfs_get_tree+0x22/0xd0 [876.852] path_mount+0x2d8/0x9c0 [876.852] do_mount+0x79/0x90 [876.852] __x64_sys_mount+0x8e/0xd0 [876.853] do_syscall_64+0x38/0x90 [876.899] entry_SYSCALL_64_after_hwframe+0x72/0xdc [876.958] RIP: 0033:0x7f5fbe50b76a [876.959] Code: 48 8b 0d a9 (...) [876.959] RSP: 002b:00007fff01925798 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [876.959] RAX: ffffffffffffffda RBX: 00007f5fbe694264 RCX: 00007f5fbe50b76a [876.960] RDX: 0000561bde6c8720 RSI: 0000561bde6bdec0 RDI: 0000561bde6c31a0 [876.960] RBP: 0000561bde6bdc70 R08: 0000000000000000 R09: 0000000000000001 [876.960] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [876.960] R13: 0000561bde6c31a0 R14: 0000561bde6c8720 R15: 0000561bde6bdc70 [876.960] </TASK> So fix this by setting 'inode' to NULL whenever we get an error from btrfs_iget(), and to make the code simpler, stop testing for 'ret' being -ENOENT to check if we have an inode - instead test for 'inode' being NULL or not. Having a NULL 'inode' prevents any iput() call from crashing, as iput() ignores NULL inode pointers. Also, stop testing for a NULL return value from btrfs_iget() with PTR_ERR_OR_ZERO(), because btrfs_iget() never returns NULL - in case an inode is not found, it returns ERR_PTR(-ENOENT), and in case of memory allocation failure, it returns ERR_PTR(-ENOMEM). We also don't need the extra iput() calls on the error branches for the btrfs_start_transaction() and btrfs_del_orphan_item() calls, as we have already called iput() before, so remove them. Fixes: a13bb2c0 ("btrfs: add missing iputs on orphan cleanup failure") CC: stable@vger.kernel.org # 6.4 Signed-off-by: -
Filipe Manana authored
At btrfs_orphan_cleanup(), if we were able to find the inode, we do an iput() on the inode, then if btrfs_drop_verity_items() succeeds and then either btrfs_start_transaction() or btrfs_del_orphan_item() fail, we do another iput() in the respective error paths, resulting in an extra iput() on the inode. Fix this by setting inode to NULL after the first iput(), as iput() ignores a NULL inode pointer argument. Fixes: a13bb2c0 ("btrfs: add missing iputs on orphan cleanup failure") CC: stable@vger.kernel.org # 6.4 Reviewed-by:
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Filipe Manana authored
At exclude_super_stripes(), if we happen to find a block group that has super blocks mapped to it and we are on a zoned filesystem, we error out as this is not supposed to happen, indicating either a bug or maybe some memory corruption for example. However we are exiting the function without freeing the memory allocated for the logical address of the super blocks. Fix this by freeing the logical address. Fixes: 12659251 ("btrfs: implement log-structured superblock for ZONED mode") CC: stable@vger.kernel.org # 5.10+ Reviewed-by:
Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by:
Anand Jain <anand.jain@oracle.com> Signed-off-by:
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- 11 Jul, 2023 3 commits
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Filipe Manana authored
If a task creates a new block group and that block group becomes unused before we finish its creation, at btrfs_create_pending_block_groups(), then when btrfs_mark_bg_unused() is called against the block group, we assume that the block group is currently in the list of block groups to reclaim, and we move it out of the list of new block groups and into the list of unused block groups. This has two consequences: 1) We move it out of the list of new block groups associated to the current transaction. So the block group creation is not finished and if we attempt to delete the bg because it's unused, we will not find the block group item in the extent tree (or the new block group tree), its device extent items in the device tree etc, resulting in the deletion to fail due to the missing items; 2) We don't increment the reference count on the block group when we move it to the list of unused block groups, because we assumed the block group was on the list of block groups to reclaim, and in that case it already has the correct reference count. However the block group was on the list of new block groups, in which case no extra reference was taken because it's local to the current task. This later results in doing an extra reference count decrement when removing the block group from the unused list, eventually leading the reference count to 0. This second case was caught when running generic/297 from fstests, which produced the following assertion failure and stack trace: [589.559] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4299 [589.559] ------------[ cut here ]------------ [589.559] kernel BUG at fs/btrfs/block-group.c:4299! [589.560] invalid opcode: 0000 [#1] PREEMPT SMP PTI [589.560] CPU: 8 PID: 2819134 Comm: umount Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1 [589.560] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [589.560] RIP: 0010:btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.561] Code: 68 62 da c0 (...) [589.561] RSP: 0018:ffffa55a8c3b3d98 EFLAGS: 00010246 [589.561] RAX: 0000000000000058 RBX: ffff8f030d7f2000 RCX: 0000000000000000 [589.562] RDX: 0000000000000000 RSI: ffffffff953f0878 RDI: 00000000ffffffff [589.562] RBP: ffff8f030d7f2088 R08: 0000000000000000 R09: ffffa55a8c3b3c50 [589.562] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8f05850b4c00 [589.562] R13: ffff8f030d7f2090 R14: ffff8f05850b4cd8 R15: dead000000000100 [589.563] FS: 00007f497fd2e840(0000) GS:ffff8f09dfc00000(0000) knlGS:0000000000000000 [589.563] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [589.563] CR2: 00007f497ff8ec10 CR3: 0000000271472006 CR4: 0000000000370ee0 [589.563] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [589.564] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [589.564] Call Trace: [589.564] <TASK> [589.565] ? __die_body+0x1b/0x60 [589.565] ? die+0x39/0x60 [589.565] ? do_trap+0xeb/0x110 [589.565] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.566] ? do_error_trap+0x6a/0x90 [589.566] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.566] ? exc_invalid_op+0x4e/0x70 [589.566] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.567] ? asm_exc_invalid_op+0x16/0x20 [589.567] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.567] ? btrfs_free_block_groups+0x449/0x4a0 [btrfs] [589.567] close_ctree+0x35d/0x560 [btrfs] [589.568] ? fsnotify_sb_delete+0x13e/0x1d0 [589.568] ? dispose_list+0x3a/0x50 [589.568] ? evict_inodes+0x151/0x1a0 [589.568] generic_shutdown_super+0x73/0x1a0 [589.569] kill_anon_super+0x14/0x30 [589.569] btrfs_kill_super+0x12/0x20 [btrfs] [589.569] deactivate_locked_super+0x2e/0x70 [589.569] cleanup_mnt+0x104/0x160 [589.570] task_work_run+0x56/0x90 [589.570] exit_to_user_mode_prepare+0x160/0x170 [589.570] syscall_exit_to_user_mode+0x22/0x50 [589.570] ? __x64_sys_umount+0x12/0x20 [589.571] do_syscall_64+0x48/0x90 [589.571] entry_SYSCALL_64_after_hwframe+0x72/0xdc [589.571] RIP: 0033:0x7f497ff0a567 [589.571] Code: af 98 0e (...) [589.572] RSP: 002b:00007ffc98347358 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [589.572] RAX: 0000000000000000 RBX: 00007f49800b8264 RCX: 00007f497ff0a567 [589.572] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000557f558abfa0 [589.573] RBP: 0000557f558a6ba0 R08: 0000000000000000 R09: 00007ffc98346100 [589.573] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [589.573] R13: 0000557f558abfa0 R14: 0000557f558a6cb0 R15: 0000557f558a6dd0 [589.573] </TASK> [589.574] Modules linked in: dm_snapshot dm_thin_pool (...) [589.576] ---[ end trace 0000000000000000 ]--- Fix this by adding a runtime flag to the block group to tell that the block group is still in the list of new block groups, and therefore it should not be moved to the list of unused block groups, at btrfs_mark_bg_unused(), until the flag is cleared, when we finish the creation of the block group at btrfs_create_pending_block_groups(). Fixes: a9f18971 ("btrfs: move out now unused BG from the reclaim list") CC: stable@vger.kernel.org # 5.15+ Signed-off-by:
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Christoph Hellwig authored
The mirror_num_ret is allowed to be NULL, although it has to be set when smap is set. Unfortunately that is not a well enough specifiable invariant for static type checkers, so add a NULL check to make sure they are fine. Fixes: 03793cbb ("btrfs: add fast path for single device io in __btrfs_map_block") Reported-by:
Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by:
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Josef Bacik authored
Syzbot reported a panic that looks like this: assertion failed: fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED, in fs/btrfs/ioctl.c:465 ------------[ cut here ]------------ kernel BUG at fs/btrfs/messages.c:259! RIP: 0010:btrfs_assertfail+0x2c/0x30 fs/btrfs/messages.c:259 Call Trace: <TASK> btrfs_exclop_balance fs/btrfs/ioctl.c:465 [inline] btrfs_ioctl_balance fs/btrfs/ioctl.c:3564 [inline] btrfs_ioctl+0x531e/0x5b30 fs/btrfs/ioctl.c:4632 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The reproducer is running a balance and a cancel or pause in parallel. The way balance finishes is a bit wonky, if we were paused we need to save the balance_ctl in the fs_info, but clear it otherwise and cleanup. However we rely on the return values being specific errors, or having a cancel request or no pause request. If balance completes and returns 0, but we have a pause or cancel request we won't do the appropriate cleanup, and then the next time we try to start a balance we'll trip this ASSERT. The error handling is just wrong here, we always want to clean up, unless we got -ECANCELLED and we set the appropriate pause flag in the exclusive op. With this patch the reproducer ran for an hour without tripping, previously it would trip in less than a few minutes. Reported-by: syzbot+c0f3acf145cb465426d5@syzkaller.appspotmail.com CC: stable@vger.kernel.org # 6.1+ Signed-off-by:
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- 19 Jun, 2023 18 commits
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Filipe Manana authored
If we disable quotas while we have a relocation of a metadata block group that has extents belonging to the quota root, we can cause the relocation to fail with -ENOENT. This is because relocation builds backref nodes for extents of the quota root and later needs to walk the backrefs and access the quota root - however if in between a task disables quotas, it results in deleting the quota root from the root tree (with btrfs_del_root(), called from btrfs_quota_disable(). This can be sporadically triggered by test case btrfs/255 from fstests: $ ./check btrfs/255 FSTYP -- btrfs PLATFORM -- Linux/x86_64 debian0 6.4.0-rc6-btrfs-next-134+ #1 SMP PREEMPT_DYNAMIC Thu Jun 15 11:59:28 WEST 2023 MKFS_OPTIONS -- /dev/sdc MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1 btrfs/255 6s ... _check_dmesg: something found in dmesg (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.dmesg) - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad) --- tests/btrfs/255.out 2023-03-02 21:47:53.876609426 +0000 +++ /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad 2023-06-16 10:20:39.267563212 +0100 @@ -1,2 +1,4 @@ QA output created by 255 +ERROR: error during balancing '/home/fdmanana/btrfs-tests/scratch_1': No such file or directory +There may be more info in syslog - try dmesg | tail Silence is golden ... (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/255.out /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad' to see the entire diff) Ran: btrfs/255 Failures: btrfs/255 Failed 1 of 1 tests To fix this make the quota disable operation take the cleaner mutex, as relocation of a block group also takes this mutex. This is also what we do when deleting a subvolume/snapshot, we take the cleaner mutex in the cleaner kthread (at cleaner_kthread()) and then we call btrfs_del_root() at btrfs_drop_snapshot() while under the protection of the cleaner mutex. Fixes: bed92eae ("Btrfs: qgroup implementation and prototypes") CC: stable@vger.kernel.org # 5.4+ Signed-off-by: -
Filipe Manana authored
Add a comment to struct btrfs_fs_info::dirty_cowonly_roots to mention that struct btrfs_fs_info::trans_lock is the lock that protects that list. Signed-off-by:
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Filipe Manana authored
When deleting the free space tree we are deleting the free space root from the list fs_info->dirty_cowonly_roots without taking the lock that protects it, which is struct btrfs_fs_info::trans_lock. This unsynchronized list manipulation may cause chaos if there's another concurrent manipulation of this list, such as when adding a root to it with ctree.c:add_root_to_dirty_list(). This can result in all sorts of weird failures caused by a race, such as the following crash: [337571.278245] general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] PREEMPT SMP PTI [337571.278933] CPU: 1 PID: 115447 Comm: btrfs Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1 [337571.279153] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [337571.279572] RIP: 0010:commit_cowonly_roots+0x11f/0x250 [btrfs] [337571.279928] Code: 85 38 06 00 (...) [337571.280363] RSP: 0018:ffff9f63446efba0 EFLAGS: 00010206 [337571.280582] RAX: ffff942d98ec2638 RBX: ffff9430b82b4c30 RCX: 0000000449e1c000 [337571.280798] RDX: dead000000000100 RSI: ffff9430021e4900 RDI: 0000000000036070 [337571.281015] RBP: ffff942d98ec2000 R08: ffff942d98ec2000 R09: 000000000000015b [337571.281254] R10: 0000000000000009 R11: 0000000000000001 R12: ffff942fe8fbf600 [337571.281476] R13: ffff942dabe23040 R14: ffff942dabe20800 R15: ffff942d92cf3b48 [337571.281723] FS: 00007f478adb7340(0000) GS:ffff94349fa40000(0000) knlGS:0000000000000000 [337571.281950] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [337571.282184] CR2: 00007f478ab9a3d5 CR3: 000000001e02c001 CR4: 0000000000370ee0 [337571.282416] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [337571.282647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [337571.282874] Call Trace: [337571.283101] <TASK> [337571.283327] ? __die_body+0x1b/0x60 [337571.283570] ? die_addr+0x39/0x60 [337571.283796] ? exc_general_protection+0x22e/0x430 [337571.284022] ? asm_exc_general_protection+0x22/0x30 [337571.284251] ? commit_cowonly_roots+0x11f/0x250 [btrfs] [337571.284531] btrfs_commit_transaction+0x42e/0xf90 [btrfs] [337571.284803] ? _raw_spin_unlock+0x15/0x30 [337571.285031] ? release_extent_buffer+0x103/0x130 [btrfs] [337571.285305] reset_balance_state+0x152/0x1b0 [btrfs] [337571.285578] btrfs_balance+0xa50/0x11e0 [btrfs] [337571.285864] ? __kmem_cache_alloc_node+0x14a/0x410 [337571.286086] btrfs_ioctl+0x249a/0x3320 [btrfs] [337571.286358] ? mod_objcg_state+0xd2/0x360 [337571.286577] ? refill_obj_stock+0xb0/0x160 [337571.286798] ? seq_release+0x25/0x30 [337571.287016] ? __rseq_handle_notify_resume+0x3ba/0x4b0 [337571.287235] ? percpu_counter_add_batch+0x2e/0xa0 [337571.287455] ? __x64_sys_ioctl+0x88/0xc0 [337571.287675] __x64_sys_ioctl+0x88/0xc0 [337571.287901] do_syscall_64+0x38/0x90 [337571.288126] entry_SYSCALL_64_after_hwframe+0x72/0xdc [337571.288352] RIP: 0033:0x7f478aaffe9b So fix this by locking struct btrfs_fs_info::trans_lock before deleting the free space root from that list. Fixes: a5ed9182 ("Btrfs: implement the free space B-tree") CC: stable@vger.kernel.org # 4.14+ Signed-off-by:
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Filipe Manana authored
When disabling quotas we are deleting the quota root from the list fs_info->dirty_cowonly_roots without taking the lock that protects it, which is struct btrfs_fs_info::trans_lock. This unsynchronized list manipulation may cause chaos if there's another concurrent manipulation of this list, such as when adding a root to it with ctree.c:add_root_to_dirty_list(). This can result in all sorts of weird failures caused by a race, such as the following crash: [337571.278245] general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] PREEMPT SMP PTI [337571.278933] CPU: 1 PID: 115447 Comm: btrfs Tainted: G W 6.4.0-rc6-btrfs-next-134+ #1 [337571.279153] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [337571.279572] RIP: 0010:commit_cowonly_roots+0x11f/0x250 [btrfs] [337571.279928] Code: 85 38 06 00 (...) [337571.280363] RSP: 0018:ffff9f63446efba0 EFLAGS: 00010206 [337571.280582] RAX: ffff942d98ec2638 RBX: ffff9430b82b4c30 RCX: 0000000449e1c000 [337571.280798] RDX: dead000000000100 RSI: ffff9430021e4900 RDI: 0000000000036070 [337571.281015] RBP: ffff942d98ec2000 R08: ffff942d98ec2000 R09: 000000000000015b [337571.281254] R10: 0000000000000009 R11: 0000000000000001 R12: ffff942fe8fbf600 [337571.281476] R13: ffff942dabe23040 R14: ffff942dabe20800 R15: ffff942d92cf3b48 [337571.281723] FS: 00007f478adb7340(0000) GS:ffff94349fa40000(0000) knlGS:0000000000000000 [337571.281950] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [337571.282184] CR2: 00007f478ab9a3d5 CR3: 000000001e02c001 CR4: 0000000000370ee0 [337571.282416] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [337571.282647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [337571.282874] Call Trace: [337571.283101] <TASK> [337571.283327] ? __die_body+0x1b/0x60 [337571.283570] ? die_addr+0x39/0x60 [337571.283796] ? exc_general_protection+0x22e/0x430 [337571.284022] ? asm_exc_general_protection+0x22/0x30 [337571.284251] ? commit_cowonly_roots+0x11f/0x250 [btrfs] [337571.284531] btrfs_commit_transaction+0x42e/0xf90 [btrfs] [337571.284803] ? _raw_spin_unlock+0x15/0x30 [337571.285031] ? release_extent_buffer+0x103/0x130 [btrfs] [337571.285305] reset_balance_state+0x152/0x1b0 [btrfs] [337571.285578] btrfs_balance+0xa50/0x11e0 [btrfs] [337571.285864] ? __kmem_cache_alloc_node+0x14a/0x410 [337571.286086] btrfs_ioctl+0x249a/0x3320 [btrfs] [337571.286358] ? mod_objcg_state+0xd2/0x360 [337571.286577] ? refill_obj_stock+0xb0/0x160 [337571.286798] ? seq_release+0x25/0x30 [337571.287016] ? __rseq_handle_notify_resume+0x3ba/0x4b0 [337571.287235] ? percpu_counter_add_batch+0x2e/0xa0 [337571.287455] ? __x64_sys_ioctl+0x88/0xc0 [337571.287675] __x64_sys_ioctl+0x88/0xc0 [337571.287901] do_syscall_64+0x38/0x90 [337571.288126] entry_SYSCALL_64_after_hwframe+0x72/0xdc [337571.288352] RIP: 0033:0x7f478aaffe9b So fix this by locking struct btrfs_fs_info::trans_lock before deleting the quota root from that list. Fixes: bed92eae ("Btrfs: qgroup implementation and prototypes") CC: stable@vger.kernel.org # 4.14+ Signed-off-by:
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Naohiro Aota authored
The btrfs_inode_mod_outstanding_extents trace event only shows the modified number to the number of outstanding extents. It would be helpful if we can see the resulting extent number as well. Signed-off-by:
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Jeff Layton authored
When updating the ctime, we also want to update i_version. This is just something I noticed by inspection. There is probably no way to test this today unless you can somehow get to this inode via nfsd. Still, I think it's the right thing to do for consistency's sake. David Sterba's comment: I don't see anything wrong with setting the iversion bit, however I also don't see where this would be useful. Agreed with the consistency, otherwise the time is updated when device super block is wiped or a device initialized, both are big events so missing that due to lack of iversion update seems unlikely. I'll add it to the queue, thanks. Signed-off-by:
Jeff Layton <jlayton@kernel.org> [ add comments ] Signed-off-by:
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Ben Dooks authored
The 'btrfs_compressed_bioset' struct isn't exported outside of the fs/btrfs/compression.c file, so make it static to fix the following sparse warning: fs/btrfs/compression.c:40:16: warning: symbol 'btrfs_compressed_bioset' was not declared. Should it be static? Reviewed-by:
Ben Dooks <ben.dooks@codethink.co.uk> Reviewed-by:
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Matt Corallo authored
Callers of `btrfs_reduce_alloc_profile` expect it to return exactly one allocation profile flag, and failing to do so may ultimately result in a WARN_ON and remount-ro when allocating new blocks, like the below transaction abort on 6.1. `btrfs_reduce_alloc_profile` has two ways of determining the profile, first it checks if a conversion balance is currently running and uses the profile we're converting to. If no balance is currently running, it returns the max-redundancy profile which at least one block in the selected block group has. This works by simply checking each known allocation profile bit in redundancy order. However, `btrfs_reduce_alloc_profile` has not been updated as new flags have been added - first with the `DUP` profile and later with the RAID1C34 profiles. Because of the way it checks, if we have blocks with different profiles and at least one is known, that profile will be selected. However, if none are known we may return a flag set with multiple allocation profiles set. This is currently only possible when a balance from one of the three unhandled profiles to another of the unhandled profiles is canceled after allocating at least one block using the new profile. In that case, a transaction abort like the below will occur and the filesystem will need to be mounted with -o skip_balance to get it mounted rw again (but the balance cannot be resumed without a similar abort). [770.648] ------------[ cut here ]------------ [770.648] BTRFS: Transaction aborted (error -22) [770.648] WARNING: CPU: 43 PID: 1159593 at fs/btrfs/extent-tree.c:4122 find_free_extent+0x1d94/0x1e00 [btrfs] [770.648] CPU: 43 PID: 1159593 Comm: btrfs Tainted: G W 6.1.0-0.deb11.7-powerpc64le #1 Debian 6.1.20-2~bpo11+1a~test [770.648] Hardware name: T2P9D01 REV 1.00 POWER9 0x4e1202 opal:skiboot-bc106a0 PowerNV [770.648] NIP: c00800000f6784fc LR: c00800000f6784f8 CTR: c000000000d746c0 [770.648] REGS: c000200089afe9a0 TRAP: 0700 Tainted: G W (6.1.0-0.deb11.7-powerpc64le Debian 6.1.20-2~bpo11+1a~test) [770.648] MSR: 9000000002029033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE> CR: 28848282 XER: 20040000 [770.648] CFAR: c000000000135110 IRQMASK: 0 GPR00: c00800000f6784f8 c000200089afec40 c00800000f7ea800 0000000000000026 GPR04: 00000001004820c2 c000200089afea00 c000200089afe9f8 0000000000000027 GPR08: c000200ffbfe7f98 c000000002127f90 ffffffffffffffd8 0000000026d6a6e8 GPR12: 0000000028848282 c000200fff7f3800 5deadbeef0000122 c00000002269d000 GPR16: c0002008c7797c40 c000200089afef17 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000001 c000200008bc5a98 0000000000000001 GPR24: 0000000000000000 c0000003c73088d0 c000200089afef17 c000000016d3a800 GPR28: c0000003c7308800 c00000002269d000 ffffffffffffffea 0000000000000001 [770.648] NIP [c00800000f6784fc] find_free_extent+0x1d94/0x1e00 [btrfs] [770.648] LR [c00800000f6784f8] find_free_extent+0x1d90/0x1e00 [btrfs] [770.648] Call Trace: [770.648] [c000200089afec40] [c00800000f6784f8] find_free_extent+0x1d90/0x1e00 [btrfs] (unreliable) [770.648] [c000200089afed30] [c00800000f681398] btrfs_reserve_extent+0x1a0/0x2f0 [btrfs] [770.648] [c000200089afeea0] [c00800000f681bf0] btrfs_alloc_tree_block+0x108/0x670 [btrfs] [770.648] [c000200089afeff0] [c00800000f66bd68] __btrfs_cow_block+0x170/0x850 [btrfs] [770.648] [c000200089aff100] [c00800000f66c58c] btrfs_cow_block+0x144/0x288 [btrfs] [770.648] [c000200089aff1b0] [c00800000f67113c] btrfs_search_slot+0x6b4/0xcb0 [btrfs] [770.648] [c000200089aff2a0] [c00800000f679f60] lookup_inline_extent_backref+0x128/0x7c0 [btrfs] [770.648] [c000200089aff3b0] [c00800000f67b338] lookup_extent_backref+0x70/0x190 [btrfs] [770.648] [c000200089aff470] [c00800000f67b54c] __btrfs_free_extent+0xf4/0x1490 [btrfs] [770.648] [c000200089aff5a0] [c00800000f67d770] __btrfs_run_delayed_refs+0x328/0x1530 [btrfs] [770.648] [c000200089aff740] [c00800000f67ea2c] btrfs_run_delayed_refs+0xb4/0x3e0 [btrfs] [770.648] [c000200089aff800] [c00800000f699aa4] btrfs_commit_transaction+0x8c/0x12b0 [btrfs] [770.648] [c000200089aff8f0] [c00800000f6dc628] reset_balance_state+0x1c0/0x290 [btrfs] [770.648] [c000200089aff9a0] [c00800000f6e2f7c] btrfs_balance+0x1164/0x1500 [btrfs] [770.648] [c000200089affb40] [c00800000f6f8e4c] btrfs_ioctl+0x2b54/0x3100 [btrfs] [770.648] [c000200089affc80] [c00000000053be14] sys_ioctl+0x794/0x1310 [770.648] [c000200089affd70] [c00000000002af98] system_call_exception+0x138/0x250 [770.648] [c000200089affe10] [c00000000000c654] system_call_common+0xf4/0x258 [770.648] --- interrupt: c00 at 0x7fff94126800 [770.648] NIP: 00007fff94126800 LR: 0000000107e0b594 CTR: 0000000000000000 [770.648] REGS: c000200089affe80 TRAP: 0c00 Tainted: G W (6.1.0-0.deb11.7-powerpc64le Debian 6.1.20-2~bpo11+1a~test) [770.648] MSR: 900000000000d033 <SF,HV,EE,PR,ME,IR,DR,RI,LE> CR: 24002848 XER: 00000000 [770.648] IRQMASK: 0 GPR00: 0000000000000036 00007fffc9439da0 00007fff94217100 0000000000000003 GPR04: 00000000c4009420 00007fffc9439ee8 0000000000000000 0000000000000000 GPR08: 00000000803c7416 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 00007fff9467d120 0000000107e64c9c 0000000107e64d0a GPR16: 0000000107e64d06 0000000107e64cf1 0000000107e64cc4 0000000107e64c73 GPR20: 0000000107e64c31 0000000107e64bf1 0000000107e64be7 0000000000000000 GPR24: 0000000000000000 00007fffc9439ee0 0000000000000003 0000000000000001 GPR28: 00007fffc943f713 0000000000000000 00007fffc9439ee8 0000000000000000 [770.648] NIP [00007fff94126800] 0x7fff94126800 [770.648] LR [0000000107e0b594] 0x107e0b594 [770.648] --- interrupt: c00 [770.648] Instruction dump: [770.648] 3b00ffe4 e8898828 481175f5 60000000 4bfff4fc 3be00000 4bfff570 3d220000 [770.648] 7fc4f378 e8698830 4811cd95 e8410018 <0fe00000> f9c10060 f9e10068 fa010070 [770.648] ---[ end trace 0000000000000000 ]--- [770.648] BTRFS: error (device dm-2: state A) in find_free_extent_update_loop:4122: errno=-22 unknown [770.648] BTRFS info (device dm-2: state EA): forced readonly [770.648] BTRFS: error (device dm-2: state EA) in __btrfs_free_extent:3070: errno=-22 unknown [770.648] BTRFS error (device dm-2: state EA): failed to run delayed ref for logical 17838685708288 num_bytes 24576 type 184 action 2 ref_mod 1: -22 [770.648] BTRFS: error (device dm-2: state EA) in btrfs_run_delayed_refs:2144: errno=-22 unknown [770.648] BTRFS: error (device dm-2: state EA) in reset_balance_state:3599: errno=-22 unknown Fixes: 47e6f742 ("btrfs: add support for 3-copy replication (raid1c3)") Fixes: 8d6fac00 ("btrfs: add support for 4-copy replication (raid1c4)") CC: stable@vger.kernel.org # 5.10+ Signed-off-by:
Matt Corallo <blnxfsl@bluematt.me> Reviewed-by:
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Qu Wenruo authored
Since the scrub rework introduced by commit 2af2aaf9 ("btrfs: scrub: introduce structure for new BTRFS_STRIPE_LEN based interface") and later commits, scrub only needs one single workqueue, fs_info::scrub_worker. That scrub_wr_completion_workers is initially to handle the delay work after write bios finished. But the new scrub code goes submit-and-wait for write bios, thus all the work are done inside the scrub_worker. The last user of fs_info::scrub_wr_completion_workers is removed in commit 16f93993 ("btrfs: scrub: remove the old writeback infrastructure"), so we can safely remove the workqueue. Reviewed-by:
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Qu Wenruo authored
Since the rework of scrub introduced by commit 2af2aaf9 ("btrfs: scrub: introduce structure for new BTRFS_STRIPE_LEN based interface") and later commits, scrub no longer keeps its data checksum inside sctx. Instead we have scrub_stripe::csums for the checksum of the stripe. Thus we can remove the unused scrub_ctx::csum_list member. Reviewed-by:
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Filipe Manana authored
During truncation we reserve 2 metadata units when starting a transaction (reserved space goes to fs_info->trans_block_rsv) and then attempt to migrate 1 unit (min_size bytes) from fs_info->trans_block_rsv into the local block reserve. If we ever fail we trigger a BUG_ON(), which should never happen, because we reserved 2 units. However if we happen to fail for some reason, we don't need to be so dire and hit a BUG_ON(), we can just error out the truncation and, since this is highly unexpected, surround the error check with WARN_ON(), to get an informative stack trace and tag the branh as 'unlikely'. Also make the 'min_size' variable const, since it's not supposed to ever change and any accidental change could possibly make the space migration not so unlikely to fail. Reviewed-by:
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Filipe Manana authored
During the transaction commit path, at create_pending_snapshot(), there is no need to BUG_ON() in case we fail to get a dir index for the snapshot in the parent directory. This should fail very rarely because the parent inode should be loaded in memory already, with the respective delayed inode created and the parent inode's index_cnt field already initialized. However if it fails, it may be -ENOMEM like the comment at create_pending_snapshot() says or any error returned by btrfs_search_slot() through btrfs_set_inode_index_count(), which can be pretty much anything such as -EIO or -EUCLEAN for example. So the comment is not correct when it says it can only be -ENOMEM. However doing a BUG_ON() here is overkill, since we can instead abort the transaction and return the error. Note that any error returned by create_pending_snapshot() will eventually result in a transaction abort at cleanup_transaction(), called from btrfs_commit_transaction(), but we can explicitly abort the transaction at this point instead so that we get a stack trace to tell us that the call to btrfs_set_inode_index() failed. So just abort the transaction and return in case btrfs_set_inode_index() returned an error at create_pending_snapshot(). Reviewed-by:
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Filipe Manana authored
There's really no need to BUG_ON() if we find a symlink with an extent that is not inline or is compressed. We can just make send fail with an error (-EUCLEAN) and log an informative error message, so just do that instead of BUG_ON(). Reviewed-by:
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Filipe Manana authored
When dropping inode items from a log tree at drop_inode_items(), we this BUG_ON() on the result of btrfs_search_slot() because we don't expect an exact match since having a key with an offset of (u64)-1 is unexpected. That is generally true, but for dir index keys for example, we can get a key with such an offset value, even though it's very unlikely and it would take ages to increase the sequence counter for a dir index up to (u64)-1. We can deal with an exact match, we just have to delete the key at that slot, so there is really no need to BUG_ON(), error out or trigger any warning. So remove the BUG_ON(). Reviewed-by:
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Filipe Manana authored
There's no need to BUG_ON() at split_item() if the leaf does not have enough free space for the new item, we can just return -ENOSPC since the caller can deal with errors from split_item(). Also, as this is a very unlikely condition to happen, because the caller has invoked setup_leaf_for_split() before calling split_item(), surround the condition with a WARN_ON() which makes it easier to notice this unexpected condition and tags the if branch with 'unlikely' as well. I've actually once hit this BUG_ON() with some incorrect code changes I had, which was very inconvenient as it required rebooting the VM. Reviewed-by:
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Filipe Manana authored
At btrfs_del_ptr(), instead of doing a BUG_ON() in case we fail to record tree mod log operations, do a transaction abort and return the error to the callers. There's really no need for the BUG_ON() as we can release all resources in the context of all callers, and we have to abort because other future tree searches that use the tree mod log (btrfs_search_old_slot()) may get inconsistent results if other operations modify the tree after that failure and before the tree mod log based search. This implies btrfs_del_ptr() return an int instead of void, and making all callers check for returned errors. Signed-off-by:
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Filipe Manana authored
At insert_ptr(), instead of doing a BUG_ON() in case we fail to record tree mod log operations, do a transaction abort and return the error to the callers. There's really no need for the BUG_ON() as we can release all resources in the context of all callers, and we have to abort because other future tree searches that use the tree mod log (btrfs_search_old_slot()) may get inconsistent results if other operations modify the tree after that failure and before the tree mod log based search. This implies making insert_ptr() return an int instead of void, and making all callers check for returned errors. Signed-off-by:
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Filipe Manana authored
At insert_new_root(), instead of doing a BUG_ON() in case we fail to record the tree mod log operation, just return the error to the callers after releasing the allocated tree block. At this point we haven't made any changes to the b+tree, so we haven't left it in an inconsistent state and therefore have no need to abort the transaction. All we need to do is to unlock and free the extent buffer we just allocated with the purpose of making it the new root. Reviewed-by:
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