| Message ID | 20240731-debug-v3-4-f9b7ed479b10@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: fix relocation on RAID stripe-tree filesystems | expand |
On Wed, Jul 31, 2024 at 10:43:06PM +0200, Johannes Thumshirn wrote: > From: Johannes Thumshirn <jthumshirn@wdc.com> > > On relocation we're doing readahead on the relocation inode, but if the > filesystem is backed by a RAID stripe tree we can get ENOENT (e.g. due to > preallocated extents not being mapped in the RST) from the lookup. > > But readahead doesn't handle the error and submits invalid reads to the > device, causing an assertion in the scatter-gather list code: > > BTRFS info (device nvme1n1): balance: start -d -m -s > BTRFS info (device nvme1n1): relocating block group 6480920576 flags data|raid0 > BTRFS error (device nvme1n1): cannot find raid-stripe for logical [6481928192, 6481969152] devid 2, profile raid0 > ------------[ cut here ]------------ > kernel BUG at include/linux/scatterlist.h:115! > Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI > CPU: 0 PID: 1012 Comm: btrfs Not tainted 6.10.0-rc7+ #567 > RIP: 0010:__blk_rq_map_sg+0x339/0x4a0 > RSP: 0018:ffffc90001a43820 EFLAGS: 00010202 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffea00045d4802 > RDX: 0000000117520000 RSI: 0000000000000000 RDI: ffff8881027d1000 > RBP: 0000000000003000 R08: ffffea00045d4902 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000001000 R12: ffff8881003d10b8 > R13: ffffc90001a438f0 R14: 0000000000000000 R15: 0000000000003000 > FS: 00007fcc048a6900(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 000000002cd11000 CR3: 00000001109ea001 CR4: 0000000000370eb0 > Call Trace: > <TASK> > ? __die_body.cold+0x14/0x25 > ? die+0x2e/0x50 > ? do_trap+0xca/0x110 > ? do_error_trap+0x65/0x80 > ? __blk_rq_map_sg+0x339/0x4a0 > ? exc_invalid_op+0x50/0x70 > ? __blk_rq_map_sg+0x339/0x4a0 > ? asm_exc_invalid_op+0x1a/0x20 > ? __blk_rq_map_sg+0x339/0x4a0 > nvme_prep_rq.part.0+0x9d/0x770 > nvme_queue_rq+0x7d/0x1e0 > __blk_mq_issue_directly+0x2a/0x90 > ? blk_mq_get_budget_and_tag+0x61/0x90 > blk_mq_try_issue_list_directly+0x56/0xf0 > blk_mq_flush_plug_list.part.0+0x52b/0x5d0 > __blk_flush_plug+0xc6/0x110 > blk_finish_plug+0x28/0x40 > read_pages+0x160/0x1c0 > page_cache_ra_unbounded+0x109/0x180 > relocate_file_extent_cluster+0x611/0x6a0 > ? btrfs_search_slot+0xba4/0xd20 > ? balance_dirty_pages_ratelimited_flags+0x26/0xb00 > relocate_data_extent.constprop.0+0x134/0x160 > relocate_block_group+0x3f2/0x500 > btrfs_relocate_block_group+0x250/0x430 > btrfs_relocate_chunk+0x3f/0x130 > btrfs_balance+0x71b/0xef0 > ? kmalloc_trace_noprof+0x13b/0x280 > btrfs_ioctl+0x2c2e/0x3030 > ? kvfree_call_rcu+0x1e6/0x340 > ? list_lru_add_obj+0x66/0x80 > ? mntput_no_expire+0x3a/0x220 > __x64_sys_ioctl+0x96/0xc0 > do_syscall_64+0x54/0x110 > entry_SYSCALL_64_after_hwframe+0x76/0x7e > RIP: 0033:0x7fcc04514f9b > Code: Unable to access opcode bytes at 0x7fcc04514f71. > RSP: 002b:00007ffeba923370 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fcc04514f9b > RDX: 00007ffeba923460 RSI: 00000000c4009420 RDI: 0000000000000003 > RBP: 0000000000000000 R08: 0000000000000013 R09: 0000000000000001 > R10: 00007fcc043fbba8 R11: 0000000000000246 R12: 00007ffeba924fc5 > R13: 00007ffeba923460 R14: 0000000000000002 R15: 00000000004d4bb0 > </TASK> > Modules linked in: > ---[ end trace 0000000000000000 ]--- > RIP: 0010:__blk_rq_map_sg+0x339/0x4a0 > RSP: 0018:ffffc90001a43820 EFLAGS: 00010202 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffea00045d4802 > RDX: 0000000117520000 RSI: 0000000000000000 RDI: ffff8881027d1000 > RBP: 0000000000003000 R08: ffffea00045d4902 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000001000 R12: ffff8881003d10b8 > R13: ffffc90001a438f0 R14: 0000000000000000 R15: 0000000000003000 > FS: 00007fcc048a6900(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007fcc04514f71 CR3: 00000001109ea001 CR4: 0000000000370eb0 > Kernel panic - not syncing: Fatal exception > Kernel Offset: disabled > ---[ end Kernel panic - not syncing: Fatal exception ]--- > > So in case of a relocation on a RAID stripe-tree based file system, skip > the readahead. > > Cc: Josef Bacik <josef@toxicpanda.com> > Cc: Filipe Manana <fdmanana@suse.com> > Reviewed-by: Josef Bacik <josef@toxicpanda.com> > Reviewed-by: Qu Wenruo <wqu@suse.com> > Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > --- > fs/btrfs/relocation.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c > index 0533d0f82dc9..72fb43b4d27c 100644 > --- a/fs/btrfs/relocation.c > +++ b/fs/btrfs/relocation.c > @@ -36,6 +36,7 @@ > #include "relocation.h" > #include "super.h" > #include "tree-checker.h" > +#include "raid-stripe-tree.h" > > /* > * Relocation overview > @@ -2965,21 +2966,26 @@ static int relocate_one_folio(struct reloc_control *rc, > u64 folio_end; > u64 cur; > int ret; > + bool use_rst = const bool > + btrfs_need_stripe_tree_update(fs_info, rc->block_group->flags); > > ASSERT(index <= last_index); > folio = filemap_lock_folio(inode->i_mapping, index); > if (IS_ERR(folio)) { > - page_cache_sync_readahead(inode->i_mapping, ra, NULL, > - index, last_index + 1 - index); > + if (!use_rst) > + page_cache_sync_readahead(inode->i_mapping, ra, NULL, Please add a comment why readahead is skipped for RST (along the lines in the changelog).
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 0533d0f82dc9..72fb43b4d27c 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -36,6 +36,7 @@ #include "relocation.h" #include "super.h" #include "tree-checker.h" +#include "raid-stripe-tree.h" /* * Relocation overview @@ -2965,21 +2966,26 @@ static int relocate_one_folio(struct reloc_control *rc, u64 folio_end; u64 cur; int ret; + bool use_rst = + btrfs_need_stripe_tree_update(fs_info, rc->block_group->flags); ASSERT(index <= last_index); folio = filemap_lock_folio(inode->i_mapping, index); if (IS_ERR(folio)) { - page_cache_sync_readahead(inode->i_mapping, ra, NULL, - index, last_index + 1 - index); + if (!use_rst) + page_cache_sync_readahead(inode->i_mapping, ra, NULL, + index, + last_index + 1 - index); folio = __filemap_get_folio(inode->i_mapping, index, - FGP_LOCK | FGP_ACCESSED | FGP_CREAT, mask); + FGP_LOCK | FGP_ACCESSED | FGP_CREAT, + mask); if (IS_ERR(folio)) return PTR_ERR(folio); } WARN_ON(folio_order(folio)); - if (folio_test_readahead(folio)) + if (folio_test_readahead(folio) && !use_rst) page_cache_async_readahead(inode->i_mapping, ra, NULL, folio, last_index + 1 - index);