Message ID | 1408524679-13583-1-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
On 8/20/14, 3:51 AM, Liu Bo wrote: > The crash is > > ------------[ cut here ]------------ > kernel BUG at fs/btrfs/extent_io.c:2124! > invalid opcode: 0000 [#1] SMP ... > --- > v2: > - Improve the commit log to be clear, suggested by Eric. Well, I had specifically asked for it to include details on when the regression occurred, but didn't get that... ;) If you state that it's a regression, people may start wondering if their kernels are vulnerable, how far back into -stable it should go, which distros should pick up the fix, etc. If you don't say when it regressed, we're all left wondering... Thanks, -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Aug 22, 2014 at 10:32:13AM -0500, Eric Sandeen wrote: > On 8/20/14, 3:51 AM, Liu Bo wrote: > > The crash is > > > > ------------[ cut here ]------------ > > kernel BUG at fs/btrfs/extent_io.c:2124! > > invalid opcode: 0000 [#1] SMP > > ... > > > --- > > v2: > > - Improve the commit log to be clear, suggested by Eric. > > Well, I had specifically asked for it to include details on when > the regression occurred, but didn't get that... ;) > > If you state that it's a regression, people may start wondering > if their kernels are vulnerable, how far back into -stable it > should go, which distros should pick up the fix, etc. If you > don't say when it regressed, we're all left wondering... Oh yeah, now I get it :) thanks, -liubo > > Thanks, > > -Eric > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 3af4966..be41e4d 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2602,6 +2602,7 @@ static void end_bio_extent_readpage(struct bio *bio, int err) test_bit(BIO_UPTODATE, &bio->bi_flags); if (err) uptodate = 0; + offset += len; continue; } }
The crash is ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:2124! invalid opcode: 0000 [#1] SMP ... CPU: 3 PID: 88 Comm: kworker/u8:7 Not tainted 3.17.0-0.rc1.git0.1.fc22.x86_64 #1 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 Workqueue: btrfs-endio normal_work_helper [btrfs] task: ffff8800d7152700 ti: ffff8800d729c000 task.ti: ffff8800d729c000 RIP: 0010:[<ffffffffa02d6055>] [<ffffffffa02d6055>] end_bio_extent_readpage+0xb45/0xcd0 [btrfs] Call Trace: [<ffffffff810c3ef8>] ? __enqueue_entity+0x78/0x80 [<ffffffff810ca969>] ? enqueue_entity+0x2e9/0x990 [<ffffffff813464ab>] bio_endio+0x6b/0xa0 [<ffffffff813464f2>] bio_endio_nodec+0x12/0x20 [<ffffffffa02ab217>] end_workqueue_fn+0x37/0x40 [btrfs] [<ffffffffa02e4b5d>] normal_work_helper+0xbd/0x280 [btrfs] [<ffffffff810ac4fe>] process_one_work+0x17e/0x430 [<ffffffff810ace8b>] worker_thread+0x6b/0x4a0 [<ffffffff810ace20>] ? rescuer_thread+0x2a0/0x2a0 [<ffffffff810b1fca>] kthread+0xea/0x100 [<ffffffff810b1ee0>] ? kthread_create_on_node+0x1a0/0x1a0 [<ffffffff8173dd7c>] ret_from_fork+0x7c/0xb0 [<ffffffff810b1ee0>] ? kthread_create_on_node+0x1a0/0x1a0 This is in fact a regression. It is because we forgot to increase @offset properly in reading corrupted block, so that the @offset remains unchanged, and it leads to checksum errors while reading left blocks queued up in the same bio, and then btrfs tries to iterate copies for those blocks in order to get good data, and hits the BUG_ON() which we set to avoid finding good copies for blocks without problems. Reported-by: Chris Murphy <lists@colorremedies.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- v2: - Improve the commit log to be clear, suggested by Eric. fs/btrfs/extent_io.c | 1 + 1 file changed, 1 insertion(+)