Re: bio linked list corruption.

[Dave Jones]

On Wed, Oct 26, 2016 at 07:47:51PM -0400, Dave Jones wrote:
 > On Wed, Oct 26, 2016 at 07:38:08PM -0400, Chris Mason wrote:
 >  
 >  > >-	hctx->queued++;
 >  > >-	data->hctx = hctx;
 >  > >-	data->ctx = ctx;
 >  > >+	data->hctx = alloc_data.hctx;
 >  > >+	data->ctx = alloc_data.ctx;
 >  > >+	data->hctx->queued++;
 >  > > 	return rq;
 >  > > }
 >  > 
 >  > This made it through an entire dbench 2048 run on btrfs.  My script has 
 >  > it running in a loop, but this is farther than I've gotten before.  
 >  > Looking great so far.
 > 
 > Fixed the splat during boot for me too.
 > Now the fun part, let's see if it fixed the 'weird shit' that Trinity
 > was stumbling on.

It took a while, but.. bad news.


BUG: Bad page state in process kworker/u8:12  pfn:4e0e39
page:ffffea0013838e40 count:0 mapcount:0 mapping:ffff8804a20310e0 index:0x100c
flags: 0x400000000000000c(referenced|uptodate)
page dumped because: non-NULL mapping
CPU: 3 PID: 1586 Comm: kworker/u8:12 Not tainted 4.9.0-rc3-think+ #1 
Workqueue: writeback wb_workfn
  (flush-btrfs-2)
 ffffc90000777828
 ffffffff8130d04c
 ffffea0013838e40
 ffffffff819ff654
 ffffc90000777850
 ffffffff81150e5f
 0000000000000000
 ffffea0013838e40
 400000000000000c
 ffffc90000777860
 ffffffff81150f1a
 ffffc900007778a8
Call Trace:
 [<ffffffff8130d04c>] dump_stack+0x4f/0x73
 [<ffffffff81150e5f>] bad_page+0xbf/0x120
 [<ffffffff81150f1a>] free_pages_check_bad+0x5a/0x70
 [<ffffffff81153818>] free_hot_cold_page+0x248/0x290
 [<ffffffff81153b1b>] free_hot_cold_page_list+0x2b/0x50
 [<ffffffff8115c52d>] release_pages+0x2bd/0x350
 [<ffffffff8115da62>] __pagevec_release+0x22/0x30
 [<ffffffffa00a0d4e>] extent_write_cache_pages.isra.48.constprop.63+0x32e/0x400 [btrfs]
 [<ffffffffa00a1199>] extent_writepages+0x49/0x60 [btrfs]
 [<ffffffffa0081840>] ? btrfs_releasepage+0x40/0x40 [btrfs]
 [<ffffffffa007e993>] btrfs_writepages+0x23/0x30 [btrfs]
 [<ffffffff8115ac4c>] do_writepages+0x1c/0x30
 [<ffffffff811f69f3>] __writeback_single_inode+0x33/0x180
 [<ffffffff811f71e8>] writeback_sb_inodes+0x2a8/0x5b0
 [<ffffffff811f757d>] __writeback_inodes_wb+0x8d/0xc0
 [<ffffffff811f7833>] wb_writeback+0x1e3/0x1f0
 [<ffffffff811f7d72>] wb_workfn+0xd2/0x280
 [<ffffffff810908d5>] process_one_work+0x1d5/0x490
 [<ffffffff81090875>] ? process_one_work+0x175/0x490
 [<ffffffff81090bd9>] worker_thread+0x49/0x490
 [<ffffffff81090b90>] ? process_one_work+0x490/0x490
 [<ffffffff81095d4e>] kthread+0xee/0x110
 [<ffffffff81095c60>] ? kthread_park+0x60/0x60
 [<ffffffff81790b12>] ret_from_fork+0x22/0x30