From abdd2e80a57e5f7278f47913315065f0a3d78d20 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 24 Jun 2014 17:46:58 +0100 Subject: [PATCH] Btrfs: fix crash when starting transaction Often when starting a transaction we commit the currently running transaction, which can end up writing block group caches when the current process has its journal_info set to NULL (and not to a transaction). This makes our assertion at btrfs_check_data_free_space() (current_journal != NULL) fail, resulting in a crash/hang. Therefore fix it by setting journal_info. Two different traces of this issue follow below. 1) [51502.241936] BTRFS: assertion failed: current->journal_info, file: fs/btrfs/extent-tree.c, line: 3670 [51502.242213] ------------[ cut here ]------------ [51502.242493] kernel BUG at fs/btrfs/ctree.h:3964! [51502.242669] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC (...) [51502.244010] Call Trace: [51502.244010] [] btrfs_check_data_free_space+0x395/0x3a0 [btrfs] [51502.244010] [] btrfs_write_dirty_block_groups+0x4ac/0x640 [btrfs] [51502.244010] [] commit_cowonly_roots+0x164/0x226 [btrfs] [51502.244010] [] btrfs_commit_transaction+0x4ed/0xab0 [btrfs] [51502.244010] [] ? _raw_spin_unlock+0x2b/0x40 [51502.244010] [] start_transaction+0x459/0x620 [btrfs] [51502.244010] [] btrfs_start_transaction+0x1b/0x20 [btrfs] [51502.244010] [] __unlink_start_trans+0x31/0xe0 [btrfs] [51502.244010] [] btrfs_unlink+0x37/0xc0 [btrfs] [51502.244010] [] ? do_unlinkat+0x114/0x2a0 [51502.244010] [] vfs_unlink+0xcc/0x150 [51502.244010] [] do_unlinkat+0x260/0x2a0 [51502.244010] [] ? filp_close+0x64/0x90 [51502.244010] [] ? trace_hardirqs_on_caller+0x16/0x1e0 [51502.244010] [] ? trace_hardirqs_on_thunk+0x3a/0x3f [51502.244010] [] SyS_unlinkat+0x1b/0x40 [51502.244010] [] system_call_fastpath+0x16/0x1b [51502.244010] Code: 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 89 f1 48 c7 c2 71 13 36 a0 48 89 fe 31 c0 48 c7 c7 b8 43 36 a0 48 89 e5 e8 5d b0 32 e1 <0f> 0b 0f 1f 44 00 00 55 b9 11 00 00 00 48 89 e5 41 55 49 89 f5 [51502.244010] RIP [] assfail.constprop.88+0x1e/0x20 [btrfs] 2) [25405.097230] BTRFS: assertion failed: current->journal_info, file: fs/btrfs/extent-tree.c, line: 3670 [25405.097488] ------------[ cut here ]------------ [25405.097767] kernel BUG at fs/btrfs/ctree.h:3964! [25405.097940] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC (...) [25405.100008] Call Trace: [25405.100008] [] btrfs_check_data_free_space+0x395/0x3a0 [btrfs] [25405.100008] [] btrfs_write_dirty_block_groups+0x4ac/0x640 [btrfs] [25405.100008] [] commit_cowonly_roots+0x164/0x226 [btrfs] [25405.100008] [] btrfs_commit_transaction+0x4ed/0xab0 [btrfs] [25405.100008] [] ? bit_waitqueue+0xc0/0xc0 [25405.100008] [] start_transaction+0x459/0x620 [btrfs] [25405.100008] [] btrfs_start_transaction+0x1b/0x20 [btrfs] [25405.100008] [] btrfs_create+0x47/0x210 [btrfs] [25405.100008] [] ? btrfs_permission+0x3c/0x80 [btrfs] [25405.100008] [] vfs_create+0x9b/0x130 [25405.100008] [] do_last+0x849/0xe20 [25405.100008] [] ? link_path_walk+0x79/0x820 [25405.100008] [] path_openat+0xc5/0x690 [25405.100008] [] ? trace_hardirqs_on+0xd/0x10 [25405.100008] [] ? __alloc_fd+0x32/0x1d0 [25405.100008] [] do_filp_open+0x43/0xa0 [25405.100008] [] ? __alloc_fd+0x151/0x1d0 [25405.100008] [] do_sys_open+0x13c/0x230 [25405.100008] [] ? trace_hardirqs_on_caller+0x16/0x1e0 [25405.100008] [] SyS_open+0x22/0x30 [25405.100008] [] system_call_fastpath+0x16/0x1b [25405.100008] Code: 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 89 f1 48 c7 c2 51 13 36 a0 48 89 fe 31 c0 48 c7 c7 d0 43 36 a0 48 89 e5 e8 6d b5 32 e1 <0f> 0b 0f 1f 44 00 00 55 b9 11 00 00 00 48 89 e5 41 55 49 89 f5 [25405.100008] RIP [] assfail.constprop.88+0x1e/0x20 [btrfs] Signed-off-by: Filipe David Borba Manana Signed-off-by: Chris Mason --- fs/btrfs/transaction.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 98e76a3..5f379af 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -493,6 +493,7 @@ again: smp_mb(); if (cur_trans->state >= TRANS_STATE_BLOCKED && may_wait_transaction(root, type)) { + current->journal_info = h; btrfs_commit_transaction(h, root); goto again; } -- 2.7.4