On Fri 17-06-16 20:04:34, Jan Kara wrote: > On Fri 17-06-16 13:40:33, Calvin Owens wrote: > > On Thursday 06/16 at 10:33 +0200, Jan Kara wrote: > > > Hi Calvin, > > > > > > On Wed 15-06-16 16:49:39, Calvin Owens wrote: > > > > I'm hitting the following warning on a 4.0 kernel: > > > > > > > > WARNING: CPU: 15 PID: 1005611 at fs/ext4/inode.c:233 ext4_evict_inode+0x4be/0x4d0() > > > > CPU: 15 PID: 1005611 Comm: rocksdb:bg0 Not tainted 4.0.9-60_fbk10_rc1_3974_g796b9b6 #1 > > > > Call Trace: > > > > [<ffffffff8176af8e>] dump_stack+0x4d/0x63 > > > > [<ffffffff8106c4dc>] warn_slowpath_common+0x8c/0xd0 > > > > [<ffffffff8106c5da>] warn_slowpath_null+0x1a/0x20 > > > > [<ffffffff81242c0e>] ext4_evict_inode+0x4be/0x4d0 > > > > [<ffffffff811d248b>] evict+0xbb/0x190 > > > > [<ffffffff811d2d6d>] iput+0x17d/0x1e0 > > > > [<ffffffff811ce0e0>] __dentry_kill+0x190/0x1e0 > > > > [<ffffffff811ce2d1>] dput+0x1a1/0x1f0 > > > > [<ffffffff811b952a>] __fput+0x17a/0x210 > > > > [<ffffffff811b960e>] ____fput+0xe/0x10 > > > > [<ffffffff81086dbf>] task_work_run+0xbf/0x100 > > > > [<ffffffff81002bcc>] do_notify_resume+0x7c/0x90 > > > > [<ffffffff81771529>] int_signal+0x12/0x17 > > > > > > > > Commit 822dbba ("ext4: fix warning in ext4_evict_inode()") proportedly fixed > > > > this in 3.11. The check was entirely removed in 4.6. > > > > > > OK, so this is the warning: > > > > > > WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count)); > > > > > > It was removed in 4.6 since we maintained i_ioend_count only to be able to > > > do this check and it didn't trigger for a long time. So it is interesting > > > that it actually triggered for you with 4.0. > > > > > > > Is it interesting to you that this triggers on 4.0? I can revert 600be30 and > > > > see if I can reproduce it on upstream, but since the check got removed I > > > > was wondering if there was post-4.0 work that makes it obsolete? > > > > > > It would be great. I'm attaching a revert and an additional debug patch. If > > > you can run with these two on the latest kernel (or even just apply the debug > > > patch on top of 4.0) and reproduce the issue with it, I would be grateful. > > > > Forgot to attach the patches? Or did my mailserver eat them? :) > > Sorry, probably forgot to attach. Here they are. Any luck with the patch? Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR -- 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