7c15d41016
We have a long standing problem with reversed keys that's detected by btrfs_set_item_key_safe. This is hard to reproduce so we'd like to capture more information for later analysis. Let's dump the leaf content before triggering BUG_ON() so that we can have some clue on what's going wrong. The output of tree locks should help us to debug such problem. Sample stacktrace: generic/522 [00:07:05] [26946.113381] run fstests generic/522 at 2019-04-16 00:07:05 [27161.474720] kernel BUG at fs/btrfs/ctree.c:3192! [27161.475923] invalid opcode: 0000 [#1] PREEMPT SMP [27161.477167] CPU: 0 PID: 15676 Comm: fsx Tainted: G W 5.1.0-rc5-default+ #562 [27161.478932] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014 [27161.481099] RIP: 0010:btrfs_set_item_key_safe+0x146/0x1c0 [btrfs] [27161.485369] RSP: 0018:ffffb087499e39b0 EFLAGS: 00010286 [27161.486464] RAX: 00000000ffffffff RBX: ffff941534d80e70 RCX: 0000000000024000 [27161.487929] RDX: 0000000000013039 RSI: ffffb087499e3aa5 RDI: ffffb087499e39c7 [27161.489289] RBP: 000000000000000e R08: ffff9414e0f49008 R09: 0000000000001000 [27161.490807] R10: 0000000000000000 R11: 0000000000000003 R12: ffff9414e0f48e70 [27161.492305] R13: ffffb087499e3aa5 R14: 0000000000000000 R15: 0000000000071000 [27161.493845] FS: 00007f8ea58d0b80(0000) GS:ffff94153d400000(0000) knlGS:0000000000000000 [27161.495608] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [27161.496717] CR2: 00007f8ea57a9000 CR3: 0000000016a33000 CR4: 00000000000006f0 [27161.498100] Call Trace: [27161.498771] __btrfs_drop_extents+0x6ec/0xdf0 [btrfs] [27161.499872] btrfs_log_changed_extents.isra.26+0x3a2/0x9e0 [btrfs] [27161.501114] btrfs_log_inode+0x7ff/0xdc0 [btrfs] [27161.502114] ? __mutex_unlock_slowpath+0x4b/0x2b0 [27161.503172] btrfs_log_inode_parent+0x237/0x9c0 [btrfs] [27161.504348] btrfs_log_dentry_safe+0x4a/0x70 [btrfs] [27161.505374] btrfs_sync_file+0x1b7/0x480 [btrfs] [27161.506371] __x64_sys_msync+0x180/0x210 [27161.507208] do_syscall_64+0x54/0x180 [27161.507932] entry_SYSCALL_64_after_hwframe+0x49/0xbe [27161.508839] RIP: 0033:0x7f8ea5aa9c61 [27161.512616] RSP: 002b:00007ffea2a06498 EFLAGS: 00000246 ORIG_RAX: 000000000000001a [27161.514161] RAX: ffffffffffffffda RBX: 000000000002a938 RCX: 00007f8ea5aa9c61 [27161.515376] RDX: 0000000000000004 RSI: 000000000001c9b2 RDI: 00007f8ea578d000 [27161.516572] RBP: 000000000001c07a R08: fffffffffffffff8 R09: 000000000002a000 [27161.517883] R10: 00007f8ea57a99b2 R11: 0000000000000246 R12: 0000000000000938 [27161.519080] R13: 00007f8ea578d000 R14: 000000000001c9b2 R15: 0000000000000000 [27161.520281] Modules linked in: btrfs libcrc32c xor zstd_decompress zstd_compress xxhash raid6_pq loop [last unloaded: scsi_debug] [27161.522272] ---[ end trace d5afec7ccac6a252 ]--- [27161.523111] RIP: 0010:btrfs_set_item_key_safe+0x146/0x1c0 [btrfs] [27161.527253] RSP: 0018:ffffb087499e39b0 EFLAGS: 00010286 [27161.528192] RAX: 00000000ffffffff RBX: ffff941534d80e70 RCX: 0000000000024000 [27161.529392] RDX: 0000000000013039 RSI: ffffb087499e3aa5 RDI: ffffb087499e39c7 [27161.530607] RBP: 000000000000000e R08: ffff9414e0f49008 R09: 0000000000001000 [27161.531802] R10: 0000000000000000 R11: 0000000000000003 R12: ffff9414e0f48e70 [27161.533018] R13: ffffb087499e3aa5 R14: 0000000000000000 R15: 0000000000071000 [27161.534405] FS: 00007f8ea58d0b80(0000) GS:ffff94153d400000(0000) knlGS:0000000000000000 [27161.536048] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [27161.537210] CR2: 00007f8ea57a9000 CR3: 0000000016a33000 CR4: 00000000000006f0 Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.