On Mon, May 16, 2016 at 05:06:55PM -0400, Chris Mason wrote: > Hi everyone, > > I've tried to cc most of the recent reports of this warning. It was > pretty hard to track down, but I've got a test program for it now. My > goal is to change xfs_io to add the madvise loop under > --do-horrible-things, instead of adding yet another special doio.c > function to xfstests. [...] > And now for the patch: [...]
I've applied the patch and hammered it with real workloads (mostly sbuild). They used to trigger the warning nearly immediately, with the patch all seemed ok -- so there is an improvement. I then tried your test case, and alas: [13603.998647] ------------[ cut here ]------------ [13603.998668] WARNING: CPU: 0 PID: 11291 at fs/btrfs/extent-tree.c:4233 btrfs_free_reserved_data_space_noquota+0x63/0x80 [13603.998673] Modules linked in: vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) nvidia(PO) [last unloaded: vboxdrv] [13603.998692] CPU: 0 PID: 11291 Comm: kworker/u12:15 Tainted: P O 4.6.0+ #1 [13603.998697] Hardware name: System manufacturer System Product Name/M4A77T, BIOS 2401 05/18/2011 [13603.998706] Workqueue: btrfs-delalloc btrfs_delalloc_helper [13603.998715] 0000000000000000 ffffffff813817a0 0000000000000000 0000000000000000 [13603.998722] ffffffff8108ce82 000000000000b000 ffff8802226e2e00 000000000000afff [13603.998728] ffff88022b42501c 000000000000b000 ffff8802224b5000 ffffffff81286fb3 [13603.998734] Call Trace: [13603.998745] [<ffffffff813817a0>] ? dump_stack+0x46/0x66 [13603.998753] [<ffffffff8108ce82>] ? __warn+0xe2/0x100 [13603.998762] [<ffffffff81286fb3>] ? btrfs_free_reserved_data_space_noquota+0x63/0x80 [13603.998770] [<ffffffff812a2350>] ? btrfs_clear_bit_hook+0x2d0/0x330 [13603.998776] [<ffffffff812be660>] ? clear_state_bit+0x60/0x1e0 [13603.998782] [<ffffffff812be90f>] ? __clear_extent_bit+0x12f/0x390 [13603.998788] [<ffffffff812bf6dd>] ? extent_clear_unlock_delalloc+0x5d/0x220 [13603.998795] [<ffffffff8118cea7>] ? cache_grow+0x147/0x220 [13603.998800] [<ffffffff8118d98c>] ? kmem_cache_alloc+0x12c/0x3e0 [13603.998808] [<ffffffff811c22d0>] ? igrab+0x10/0x40 [13603.998815] [<ffffffff812baf57>] ? __btrfs_add_ordered_extent+0x1c7/0x2d0 [13603.998822] [<ffffffff812a8e8f>] ? submit_compressed_extents+0x41f/0x4e0 [13603.998830] [<ffffffff812d1c86>] ? btrfs_scrubparity_helper+0x136/0x1c0 [13603.998837] [<ffffffff810a2bad>] ? process_one_work+0x1bd/0x400 [13603.998843] [<ffffffff810a2e32>] ? worker_thread+0x42/0x4b0 [13603.998850] [<ffffffff810a2df0>] ? process_one_work+0x400/0x400 [13603.998856] [<ffffffff810a8268>] ? kthread+0xb8/0xd0 [13603.998863] [<ffffffff81747d02>] ? ret_from_fork+0x22/0x40 [13603.998868] [<ffffffff810a81b0>] ? kthread_worker_fn+0x160/0x160 [13603.998873] ---[ end trace 359dcd25d6847cee ]--- [13603.999155] ------------[ cut here ]------------ [13603.999167] WARNING: CPU: 0 PID: 11291 at fs/btrfs/extent-tree.c:4233 btrfs_free_reserved_data_space_noquota+0x63/0x80 [13603.999170] Modules linked in: vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) nvidia(PO) [last unloaded: vboxdrv] [13603.999183] CPU: 0 PID: 11291 Comm: kworker/u12:15 Tainted: P W O 4.6.0+ #1 [13603.999186] Hardware name: System manufacturer System Product Name/M4A77T, BIOS 2401 05/18/2011 [13603.999193] Workqueue: btrfs-delalloc btrfs_delalloc_helper [13603.999196] 0000000000000000 ffffffff813817a0 0000000000000000 0000000000000000 [13603.999202] ffffffff8108ce82 0000000000005000 ffff8802226e2e00 0000000000004fff [13603.999208] ffff88022b42501c 0000000000005000 ffff8802224b5000 ffffffff81286fb3 [13603.999214] Call Trace: [13603.999220] [<ffffffff813817a0>] ? dump_stack+0x46/0x66 [13603.999226] [<ffffffff8108ce82>] ? __warn+0xe2/0x100 [13603.999234] [<ffffffff81286fb3>] ? btrfs_free_reserved_data_space_noquota+0x63/0x80 [13603.999241] [<ffffffff812a2350>] ? btrfs_clear_bit_hook+0x2d0/0x330 [13603.999247] [<ffffffff812be660>] ? clear_state_bit+0x60/0x1e0 [13603.999252] [<ffffffff812be90f>] ? __clear_extent_bit+0x12f/0x390 [13603.999258] [<ffffffff812bf6dd>] ? extent_clear_unlock_delalloc+0x5d/0x220 [13603.999264] [<ffffffff8118d98c>] ? kmem_cache_alloc+0x12c/0x3e0 [13603.999271] [<ffffffff811c22d0>] ? igrab+0x10/0x40 [13603.999278] [<ffffffff812baf57>] ? __btrfs_add_ordered_extent+0x1c7/0x2d0 [13603.999284] [<ffffffff812a8e8f>] ? submit_compressed_extents+0x41f/0x4e0 [13603.999292] [<ffffffff812d1c86>] ? btrfs_scrubparity_helper+0x136/0x1c0 [13603.999299] [<ffffffff810a2bad>] ? process_one_work+0x1bd/0x400 [13603.999305] [<ffffffff810a2e32>] ? worker_thread+0x42/0x4b0 [13603.999312] [<ffffffff810a2df0>] ? process_one_work+0x400/0x400 [13603.999317] [<ffffffff810a8268>] ? kthread+0xb8/0xd0 [13603.999323] [<ffffffff81747d02>] ? ret_from_fork+0x22/0x40 [13603.999329] [<ffffffff810a81b0>] ? kthread_worker_fn+0x160/0x160 [13603.999333] ---[ end trace 359dcd25d6847cef ]--- [13634.053259] ------------[ cut here ]------------ [13634.053280] WARNING: CPU: 3 PID: 11291 at fs/btrfs/extent-tree.c:4233 btrfs_free_reserved_data_space_noquota+0x63/0x80 [13634.053285] Modules linked in: vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) nvidia(PO) [last unloaded: vboxdrv] [13634.053303] CPU: 3 PID: 11291 Comm: kworker/u12:15 Tainted: P W O 4.6.0+ #1 [13634.053308] Hardware name: System manufacturer System Product Name/M4A77T, BIOS 2401 05/18/2011 [13634.053317] Workqueue: btrfs-delalloc btrfs_delalloc_helper [13634.053321] 0000000000000000 ffffffff813817a0 0000000000000000 0000000000000000 [13634.053329] ffffffff8108ce82 0000000000003000 ffff8802226e2e00 0000000000002fff [13634.053335] ffff88022ecda41c 0000000000003000 ffff880227035800 ffffffff81286fb3 [13634.053341] Call Trace: [13634.053351] [<ffffffff813817a0>] ? dump_stack+0x46/0x66 [13634.053359] [<ffffffff8108ce82>] ? __warn+0xe2/0x100 [13634.053368] [<ffffffff81286fb3>] ? btrfs_free_reserved_data_space_noquota+0x63/0x80 [13634.053376] [<ffffffff812a2350>] ? btrfs_clear_bit_hook+0x2d0/0x330 [13634.053382] [<ffffffff812be660>] ? clear_state_bit+0x60/0x1e0 [13634.053388] [<ffffffff812be90f>] ? __clear_extent_bit+0x12f/0x390 [13634.053394] [<ffffffff812bf6dd>] ? extent_clear_unlock_delalloc+0x5d/0x220 [13634.053401] [<ffffffff8118d98c>] ? kmem_cache_alloc+0x12c/0x3e0 [13634.053408] [<ffffffff811c22d0>] ? igrab+0x10/0x40 [13634.053416] [<ffffffff812baf57>] ? __btrfs_add_ordered_extent+0x1c7/0x2d0 [13634.053422] [<ffffffff812a8e8f>] ? submit_compressed_extents+0x41f/0x4e0 [13634.053430] [<ffffffff812d1c86>] ? btrfs_scrubparity_helper+0x136/0x1c0 [13634.053437] [<ffffffff810a2bad>] ? process_one_work+0x1bd/0x400 [13634.053444] [<ffffffff810a2e32>] ? worker_thread+0x42/0x4b0 [13634.053450] [<ffffffff810a2df0>] ? process_one_work+0x400/0x400 [13634.053456] [<ffffffff810a8268>] ? kthread+0xb8/0xd0 [13634.053464] [<ffffffff81747d02>] ? ret_from_fork+0x22/0x40 [13634.053470] [<ffffffff810a81b0>] ? kthread_worker_fn+0x160/0x160 [13634.053474] ---[ end trace 359dcd25d6847cf0 ]--- [13646.118422] BTRFS info (device sda1): btrfs_destroy_inode: leftover csum_bytes Here's another run on an untainted kernel built with frame pointers etc: ./dammitdave foo [ 236.500257] ------------[ cut here ]------------ [ 236.500280] WARNING: CPU: 3 PID: 2940 at fs/btrfs/extent-tree.c:4233 btrfs_free_reserved_data_space_noquota+0xdd/0x160 [ 236.500285] Modules linked in: [ 236.500295] CPU: 3 PID: 2940 Comm: dammit Not tainted 4.6.0debug+ #1 [ 236.500301] Hardware name: System manufacturer System Product Name/M4A77T, BIOS 2401 05/18/2011 [ 236.500306] 0000000000000000 0000000042ec2fb0 ffff88022d5ffbd8 ffffffff816b1920 [ 236.500315] ffffffff81f86e3f 0000000042ec2fb0 0000000000000000 0000000000000000 [ 236.500322] ffff88022d5ffc20 ffffffff81118c2c ffff88022dfd4000 0000108900000000 [ 236.500330] Call Trace: [ 236.500342] [<ffffffff816b1920>] dump_stack+0x60/0xa0 [ 236.500352] [<ffffffff81118c2c>] __warn+0x10c/0x150 [ 236.500360] [<ffffffff81118d78>] warn_slowpath_null+0x18/0x20 [ 236.500368] [<ffffffff814e389d>] btrfs_free_reserved_data_space_noquota+0xdd/0x160 [ 236.500376] [<ffffffff814e3942>] btrfs_free_reserved_data_space+0x22/0x40 [ 236.500385] [<ffffffff8152eb78>] __btrfs_buffered_write+0x748/0xa20 [ 236.500394] [<ffffffff81624bdc>] ? security_inode_need_killpriv+0x3c/0x60 [ 236.500401] [<ffffffff815345ef>] btrfs_file_write_iter+0x4ff/0xb90 [ 236.500410] [<ffffffff81341847>] __vfs_write+0x117/0x1d0 [ 236.500417] [<ffffffff8134317d>] vfs_write+0xdd/0x290 [ 236.500425] [<ffffffff813748bd>] ? __fget_light+0x4d/0x120 [ 236.500432] [<ffffffff813453ee>] SyS_pwrite64+0x9e/0xc0 [ 236.500441] [<ffffffff81db989f>] entry_SYSCALL_64_fastpath+0x17/0x93 [ 236.500446] ---[ end trace 7df747a6a0962ae6 ]--- rm foo [ 323.851851] BTRFS info (device sda1): btrfs_destroy_inode: leftover csum_bytes -- A tit a day keeps the vet away. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
