[Linux-cachefs] FSCache BUG in 3.9.9 ?

[Clusters GmbH]

Hi Folks,

I likely hit a bug in fscache using kernel 3.9.9. The problem occurs on 
a heavy loaded virtual machine after running for a while and is not 
manually reproducable. Everything works fine using kernel 3.4.6, though 
I can't tell when in between the problem was introduced. Thank you for 
you help!

FS-Cache: Assertion failed
3 == 5 is false
------------[ cut here ]------------
kernel BUG at fs/fscache/operation.c:419!
invalid opcode: 0000 [#1] SMP
Modules linked in: custom_method sbs sbshc battery acpi_memhotplug 
thermal video fan ac acpi_ipmi ipmi_msghandler cachefiles nfsv4 nfsd 
auth_rpcgss nfs_acl nfs lockd fscache sunrpc dummy psmouse serio_raw 
parport_pc crc32c_intel evdev intel_agp processor parport intel_gtt 
i2c_piix4 rtc_cmos button ata_generic pata_acpi ata_piix
CPU 1
Pid: 26846, comm: kworker/u:2 Not tainted 3.9.9-9-x86_64-clusters_smp #1 
Bochs Bochs
RIP: 0010:[<ffffffffa011abf1>]  [<ffffffffa011abf1>] 
fscache_put_operation+0x201/0x240 [fscache]
RSP: 0018:ffff8801976bbe08  EFLAGS: 00010296
RAX: 000000000000000f RBX: ffff880197f836c0 RCX: 0000000000000006
RDX: 0000000000000007 RSI: 0000000000000082 RDI: 0000000000000246
RBP: ffff880197712100 R08: 0000000000000000 R09: 00000000000001e2
R10: 0000000000000006 R11: 00000000000001e1 R12: ffffffff81ac4540
R13: ffff8801952eea00 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88019fc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffffff600400 CR3: 0000000197e2e000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process kworker/u:2 (pid: 26846, threadinfo ffff8801976ba000, task 
ffff880194c82000)
Stack:
  ffff880197f836c0 ffff880197712100 ffffffff81ac4540 ffffffff810ba1e8
  ffff880197712128 0000000094c82000 ffff880194c82000 ffff880197712100
  ffffffff81ac4540 ffff880194c82000 ffff880194c82000 ffffffff81ac4550
Call Trace:
  [<ffffffff810ba1e8>] ? process_one_work+0x168/0x3c0
  [<ffffffff810ba7d6>] ? worker_thread+0x106/0x390
  [<ffffffff810ba6d0>] ? rescuer_thread+0x250/0x250
  [<ffffffff810bf003>] ? kthread+0xb3/0xc0
  [<ffffffff810c0000>] ? cpu_clock_sample+0x30/0x60
  [<ffffffff810bef50>] ? kthread_freezable_should_stop+0x60/0x60
  [<ffffffff81656f7c>] ? ret_from_fork+0x7c/0xb0
  [<ffffffff810bef50>] ? kthread_freezable_should_stop+0x60/0x60
Code: 31 c0 e8 0e 35 53 e1 48 c7 c7 4b f3 11 a0 31 c0 e8 00 35 53 e1 8b 
73 40 ba 05 00 00 00 48 c7 c7 96 f3 11 a0 31 c0 e8 ea 34 53 e1 <0f> 0b 
48 c7 c7 47 f3 11 a0 31 c0 e8 da 34 53 e1 48 c7 c7 4b f3
RIP  [<ffffffffa011abf1>] fscache_put_operation+0x201/0x240 [fscache]
  RSP <ffff8801976bbe08>
---[ end trace 8ed2b90a2b90a97a ]---


-- 

regards
Michael Weiß