On Thu, 12 May 2011 16:54:40 +0200 Torsten Hilbrich <torsten.hilbrich@xxxxxxxxxxx> wrote: > The error can be reproduced in both linux-2.6 master > (3568bd9720b4a775f28a718fcbb462ce2f386988) and v2.6.38.6. It cannot be > reproduced in v2.6.38.5, because the error occurs only after: > > commit 1f74c190e1e97a38823c07fdc71780580a0fc03f > Author: James Bottomley <James.Bottomley@xxxxxxx> > Date: Fri Apr 22 10:39:59 2011 -0500 > > put stricter guards on queue dead checks > > commit 86cbfb5607d4b81b1a993ff689bbd2addd5d3a9b upstream. > > in the 2.6.38 stable line. A 2.6.38.5 -> 2.6.38.6 regression is presumably also a 2.6.38->2.6.39-rc regression. > Here is the error message for master: > > general protection fault: 0000 [#1] SMP > last sysfs file: > CPU 1 > Modules linked in: > > Pid: 1926, comm: sync Not tainted 2.6.39-rc7+ #39 LENOVO 20077KG/20077KG > RIP: 0010:[<ffffffff811231bf>] [<ffffffff811231bf>] > __mark_inode_dirty+0x14f/0x200 > RSP: 0018:ffff88007bebbe08 EFLAGS: 00010246 > RAX: ffff88007d031470 RBX: ffff88007d031408 RCX: ffff88007d031470 > RDX: 6b6b6b6b6b6b6b6b RSI: ffffffff81d33f2a RDI: ffffffff82002300 > RBP: ffff88007bebbe28 R08: 0000000000000000 R09: 0000000000000000 > R10: ffff88007bde3d68 R11: ffff88007c2fba6f R12: ffff88007c350300 > R13: ffff88007c350458 R14: 0000000000000000 R15: ffffffff81127e30 > FS: 00007f8306063700(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > CR2: 0000000001f40600 CR3: 000000007b968000 CR4: 00000000000006a0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process sync (pid: 1926, threadinfo ffff88007beba000, task ffff88007c610820) > Stack: > ffff88007d031550 ffffea0000082638 0000000000000000 0000000000000000 > ffff88007bebbe58 ffffffff8112a5ff ffffffff81d3c8d8 ffff88007d223eb0 > ffff880002541400 ffff88007d223eb0 ffff88007bebbe78 ffffffff8112a6b6 > Call Trace: > [<ffffffff8112a5ff>] __set_page_dirty+0x6f/0xc0 > [<ffffffff8112a6b6>] mark_buffer_dirty+0x66/0xa0 > [<ffffffff8117c3ce>] ext2_sync_super+0x8e/0xf0 > [<ffffffff8117c495>] ext2_sync_fs+0x65/0x80 > [<ffffffff81127dfe>] __sync_filesystem+0x5e/0x90 > [<ffffffff81127e4f>] sync_one_sb+0x1f/0x30 > [<ffffffff81100021>] iterate_supers+0x71/0xd0 > [<ffffffff81127e8f>] sys_sync+0x2f/0x70 > [<ffffffff819c69ab>] system_call_fastpath+0x16/0x1b > Code: e8 67 be 89 00 48 8b 05 20 47 ff 00 48 8b 53 70 48 8b 4b 68 48 89 > 43 50 48 8d 43 68 48 89 51 08 48 89 0a 49 8b 94 24 58 01 00 00 > 89 42 08 48 89 53 68 4c 89 6b 70 49 89 84 24 58 01 00 00 fe > RIP [<ffffffff811231bf>] __mark_inode_dirty+0x14f/0x200 > RSP <ffff88007bebbe08> > ---[ end trace 04d7660d6043ca51 ]--- > > If I parsed the error location correctly, it is the: > > next->prev = prev; // mov %rcx,(%rdx) > > statement from __list_del called via __list_del_entry, list_move from > the line: > > list_move(&inode->i_wb_list, &bdi->wb.b_dirty); > > in __mark_inode_dirty. rdx seems to be > > Here are the steps for reproduction: > > 1. mount an USB stick with ext2 FS (mount /dev/sdb1 /mnt) > 2. open file on USB stick for writing (cat > /mnt/foo) > 3. press some return > 4. Remove USB stick > 5. In another console run sync > > I will append the full kernel log (screenlog.0) and the configuration > (config-master) to this mail. hm, maybe *bdi was freed at this time. But if so I'd have expected __mark_inode_dirty() to crash earlier than in the list_move(). James, the cure looks worse than the disease - should we revert "put stricter guards on queue dead checks" for now? -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
