Description of problem:
A xen domU I have occasionally crashes. It happens pretty randomly, but seems as
if it might be more likely under heavier IO load. Once the kernel stack trace
happens, the domU will no longer complete any commands and I am unable to log in
on the console. Trying to destroy the domU results in it becoming a zombie and
not dying.

Version-Release number of selected component (if applicable):
Most recent packages as of 3-26-06. It may or may not matter that I'm running my
domU on top of a DRBD device (and a local LVM device for swap).

How reproducible:
Intermittent.
  

Here is the kernel dump on the dom0. It is indeed the 8th domU that has become
unresponsive.

Mar 27 01:39:36 johnny kernel: Unable to handle kernel paging request at
ffff8800e53ba000 RIP: 
Mar 27 01:39:36 johnny kernel: <ffffffff80179b5b>{__bio_clone+46}
Mar 27 01:39:36 johnny kernel: PGD 10d9067 PUD 16dd067 PMD 1807067 PTE 0
Mar 27 01:39:36 johnny kernel: Oops: 0000 [1] SMP 
Mar 27 01:39:36 johnny kernel: CPU 0 
Mar 27 01:39:36 johnny kernel: Modules linked in: xt_physdev drbd(U) ipv6 bridge
w83627hf hwmon_vid hwmon eeprom i2c_isa ip_conntrack_netbios_ns ipt_REJECT
xt_state ip_conntrack nfnetlink ipt_LOG xt_tcp
udp iptable_filter ip_tables x_tables video button battery ac lp parport_pc
parport nvram ohci1394 ieee1394 sg e100 mii i2c_nforce2 i2c_core forcedeth
dm_snapshot dm_zero dm_mirror dm_mod ext3 jbd sata_
nv libata aacraid sd_mod scsi_mod
Mar 27 01:39:36 johnny kernel: Pid: 5229, comm: xvd 8 93:02 Not tainted
2.6.15-1.2054_FC5xen0 #1
Mar 27 01:39:36 johnny kernel: RIP: e030:[<ffffffff80179b5b>]
<ffffffff80179b5b>{__bio_clone+46}
Mar 27 01:39:36 johnny kernel: RSP: e02b:ffff8800ac24d948  EFLAGS: 00010216
Mar 27 01:39:36 johnny kernel: RAX: ffff8800e53b9f50 RBX: ffff8800e49b9d40 RCX:
0000000000000050
Mar 27 01:39:36 johnny kernel: RDX: ffff8800e53b9e80 RSI: ffff8800e53ba000 RDI:
ffff8800a9785d30
Mar 27 01:39:36 johnny kernel: RBP: ffff8800e702b338 R08: 0000000006ffb100 R09:
ffff88000189c000
Mar 27 01:39:36 johnny kernel: R10: 0000000000001000 R11: 0000000000000001 R12:
0000000000000023
Mar 27 01:39:36 johnny kernel: R13: ffff8800e53b9e80 R14: ffff8800e4766150 R15:
0000000000000008
Mar 27 01:39:36 johnny kernel: FS:  00002abf280251c0(0000)
GS:ffffffff80499000(0000) knlGS:0000000000000000
Mar 27 01:39:36 johnny kernel: CS:  e033 DS: 0000 ES: 0000
Mar 27 01:39:36 johnny kernel: Process xvd 8 93:02 (pid: 5229, threadinfo
ffff8800ac24c000, task ffff8800a6ff6040)
Mar 27 01:39:36 johnny kernel: Stack: ffff8800e53b9e80 ffff8800e49b9d40
ffff8800e53b9e80 ffffffff80179bed 
Mar 27 01:39:36 johnny kernel:        ffff8800e70250d0 0000000000000023
ffff8800e70250d0 ffffffff88209471 
Mar 27 01:39:36 johnny kernel:        0000000000047ffd 00000001f1ba2a08 
Mar 27 01:39:36 johnny kernel: Call Trace: <ffffffff80179bed>{bio_clone+53}
<ffffffff88209471>{:drbd:drbd_make_request_26+1046}
Mar 27 01:39:36 johnny kernel:        <ffffffff80155bbf>{mempool_alloc+66}
<ffffffff8032835c>{_spin_unlock_irqrestore+9}
Mar 27 01:39:36 johnny kernel:        <ffffffff88086544>{:dm_mod:dm_request+345}
<ffffffff8820924a>{:drbd:drbd_make_request_26+495}
Mar 27 01:39:36 johnny kernel:       
<ffffffff801e9225>{generic_make_request+365} <ffffffff801ea61a>{submit_bio+186}
Mar 27 01:39:36 johnny kernel:       
<ffffffff80266851>{dispatch_rw_block_io+994} <ffffffff80266c6a>{blkif_schedule+944}
Mar 27 01:39:36 johnny kernel:        <ffffffff80124780>{__wake_up_common+62}
<ffffffff80141339>{autoremove_wake_function+0}
Mar 27 01:39:36 johnny kernel:       
<ffffffff80140f17>{keventd_create_kthread+0} <ffffffff802668ba>{blkif_schedule+0}
Mar 27 01:39:37 johnny kernel:       
<ffffffff80140f17>{keventd_create_kthread+0} <ffffffff80141200>{kthread+212}
Mar 27 01:39:37 johnny kernel:        <ffffffff8010b856>{child_rip+8}
<ffffffff80140f17>{keventd_create_kthread+0}
Mar 27 01:39:37 johnny kernel:        <ffffffff8014112c>{kthread+0}
<ffffffff8010b84e>{child_rip+0}
Mar 27 01:39:37 johnny kernel: 
Mar 27 01:39:37 johnny kernel: Code: f3 a4 48 8b 02 48 89 03 48 8b 42 10 48 89
43 10 48 83 4b 18 
Mar 27 01:39:37 johnny kernel: RIP <ffffffff80179b5b>{__bio_clone+46} RSP
<ffff8800ac24d948>
Mar 27 01:39:37 johnny kernel: CR2: ffff8800e53ba000