Re: [Bug 30882] Automatic process group scheduling causes crashes after a while

[Andrew Morton <akpm@linux-foundation.org>]

(switched to email.  Please respond via emailed reply-to-all, not via the
bugzilla web interface).

Seems that we have a nasty involving autofs, nfs and the VFS.

Mehmet, the kernel should have printed some diagnostics prior to doing
the BUG() call:

			if (dentry->d_count != 0) {
				printk(KERN_ERR
				       "BUG: Dentry %p{i=%lx,n=%s}"
				       " still in use (%d)"
				       " [unmount of %s %s]\n",
				       dentry,
				       dentry->d_inode ?
				       dentry->d_inode->i_ino : 0UL,
				       dentry->d_name.name,
				       dentry->d_count,
				       dentry->d_sb->s_type->name,
				       dentry->d_sb->s_id);
				BUG();
			}

Please find those in the log and email them to use - someone might find
it useful.


On Tue, 15 Mar 2011 21:02:23 GMT
bugzilla-daemon@bugzilla.kernel.org wrote:

> https://bugzilla.kernel.org/show_bug.cgi?id=30882
> 
> 
> 
> 
> 
> --- Comment #4 from Mehmet Giritli <mehmet@giritli.eu>  2011-03-15 21:02:22 ---
> Here is that crash happening again, the system was NOT running overclocked or
> anything...
> 
> [ 1860.156122] ------------[ cut here ]------------
> [ 1860.156124] kernel BUG at fs/dcache.c:943!
> [ 1860.156126] invalid opcode: 0000 [#1] SMP 
> [ 1860.156127] last sysfs file: /sys/devices/platform/it87.552/fan3_input
> [ 1860.156128] CPU 3 
> [ 1860.156129] Modules linked in: iptable_mangle iptable_nat nf_nat ipt_LOG
> xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_state xt_mac iptable_filter
> xt_multiport xt_mark xt_conntrack xt_connmark nf_conntrack ip_tables x_tables
> nvidia(P)
> [ 1860.156137] 
> [ 1860.156139] Pid: 7388, comm: umount.nfs Tainted: P            2.6.38-rc8 #9
> Gigabyte Technology Co., Ltd. GA-790FXTA-UD5/GA-790FXTA-UD5
> [ 1860.156142] RIP: 0010:[<ffffffff810e9648>]  [<ffffffff810e9648>]
> shrink_dcache_for_umount_subtree+0x268/0x270
> [ 1860.156147] RSP: 0018:ffff8800be82fe08  EFLAGS: 00010296
> [ 1860.156149] RAX: 0000000000000065 RBX: ffff88023f96e600 RCX:
> 000000000003ffff
> [ 1860.156150] RDX: ffffffff8161f888 RSI: 0000000000000046 RDI:
> ffffffff8174c9f8
> [ 1860.156151] RBP: ffff88023f96e600 R08: 0000000000012c37 R09:
> 0000000000000006
> [ 1860.156152] R10: 0000000000000000 R11: 0000000000000000 R12:
> ffff88023a07f5e0
> [ 1860.156154] R13: ffff88023f96e65c R14: ffff8800be82ff18 R15:
> ffff880211d38740
> [ 1860.156155] FS:  00007f3428cb2700(0000) GS:ffff8800bfac0000(0000)
> knlGS:00000000f74186c0
> [ 1860.156156] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 1860.156157] CR2: 00007f7c97da1000 CR3: 00000000bea08000 CR4:
> 00000000000006e0
> [ 1860.156159] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> 0000000000000000
> [ 1860.156160] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
> 0000000000000400
> [ 1860.156161] Process umount.nfs (pid: 7388, threadinfo ffff8800be82e000, task
> ffff880211fd5640)
> [ 1860.156162] Stack:
> [ 1860.156163]  ffff88020c05ce50 0000000000000000 ffff88023fc07128
> ffff88020c05cc00
> [ 1860.156165]  ffff88023f96e6c0 ffff8800be82ff28 ffff88023f96e300
> ffffffff810e96a4
> [ 1860.156167]  ffff88023f49f480 ffff88020c05cc00 ffffffff8146d4a0
> ffffffff810d5d15
> [ 1860.156169] Call Trace:
> [ 1860.156172]  [<ffffffff810e96a4>] ? shrink_dcache_for_umount+0x54/0x60
> [ 1860.156174]  [<ffffffff810d5d15>] ? generic_shutdown_super+0x25/0x100
> [ 1860.156176]  [<ffffffff810d5e79>] ? kill_anon_super+0x9/0x40
> [ 1860.156179]  [<ffffffff81179aed>] ? nfs_kill_super+0xd/0x20
> [ 1860.156181]  [<ffffffff810d5f13>] ? deactivate_locked_super+0x43/0x70
> [ 1860.156183]  [<ffffffff810ef4d8>] ? release_mounts+0x68/0x90
> [ 1860.156185]  [<ffffffff810efa54>] ? sys_umount+0x314/0x3d0
> [ 1860.156187]  [<ffffffff8100243b>] ? system_call_fastpath+0x16/0x1b
> [ 1860.156188] Code: 8b 0a 31 d2 48 85 f6 74 07 48 8b 96 a8 00 00 00 48 05 50
> 02 00 00 48 89 de 48 c7 c7 40 3a 52 81 48 89 04 24 31 c0 e8 a1 bc 35 00 <0f> 0b
> eb fe 0f 0b eb fe 55 53 48 89 fb 48 8d 7f 68 48 83 ec 08 
> [ 1860.156201] RIP  [<ffffffff810e9648>]
> shrink_dcache_for_umount_subtree+0x268/0x270
> [ 1860.156204]  RSP <ffff8800be82fe08>
> [ 1860.156205] ---[ end trace ee03486c16c108a7 ]---
> 
> -- 
> Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug.