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<DIV><FONT face=Arial size=2><SPAN class=800325117-14022007>Hi
all,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=800325117-14022007>We are overwelmed
with panic's after io errors. Seem mdev->bc is null due to some race
condition. Here is one instance:</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=800325117-14022007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=800325117-14022007>Two node cluster,
node A and Node B. Syncsource is node A. While syncing Reads are issued on Node
B. I/O errosrs start to occur</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=800325117-14022007>on node A,
Node A panics :</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=800325117-14022007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=800325117-14022007><FONT
face="Times New Roman" size=3>Feb 11 03:15:49 drbd0: Sending NegRSDReply. sector
11620032s.<BR>Feb 11 03:15:49 drbd0: Notified peer that my disk is
broken.<BR>Feb 11 03:15:58 end_request: I/O error, dev sda, sector
59856375<BR>Feb 11 03:16:10 end_request: I/O error, dev sda, sector
59856383<BR>Feb 11 03:16:10 drbd0: Local IO failed. Detaching...<BR>Feb 11
03:16:10 Unable to handle kernel NULL pointer dereference at virtual address
00000010<BR>Feb 11 03:16:10 printing eip:<BR>Feb 11 03:16:10
ee3d0b0b<BR>Feb 11 03:16:10 299ba000 -> *pde = 00000000:7f512001<BR>Feb 11
03:16:10 00512000 -> *pme = 00000000:00000000<BR>Feb 11 03:16:10 Oops: 0000
[#1]<BR>Feb 11 03:16:10 SMP <BR>Feb 11 03:16:10 Modules linked in: drbd cn
bridge ipv6 ipmi_devintf ipmi_si ipmi_msghandler i2c_dev i2c_core binfmt_misc
dm_mirror video thermal processor fan container button battery ac shpchp
pci_hotplug e1000 piix ide_cd cdrom sg raid1 dm_mod ide_disk mptscsih mptsas
mptspi mptfc mptscsi mptbase sd_mod scsi_mod<BR>Feb 11 03:16:10 CPU:
0<BR>Feb 11 03:16:10 EIP: 0061:[<ee3d0b0b>]
Tainted: GF VLI<BR>Feb 11 03:16:10 EFLAGS: 00010292
(2.6.16.29-xen #1) <BR>Feb 11 03:16:10 EIP is at drbd_bm_write_sect+0x1b/0x1f0
[drbd]<BR>Feb 11 03:16:10 eax: 00000000 ebx: eb925000 ecx:
00000000 edx: 000001bd<BR>Feb 11 03:16:10 esi: eb925000 edi:
eb92502c ebp: eae77f50 esp: eae77f1c<BR>Feb 11 03:16:10 ds:
007b es: 007b ss: 0069<BR>Feb 11 03:16:10 Process drbd0_worker (pid:
5777, threadinfo=eae76000 task=c060b570)<BR>Feb 11 03:16:10 Stack:
<0>c0136f00 eae77f20 eae77f20 ffffffff ffffffff e7ea3550 00000000 000001bd
<BR>Feb 11 03:16:10 00000000 000001bd eb925000
eb667980 eb92502c eae77f74 ee3e2080 eb385d40 <BR>Feb 11 03:16:10
eb92502c eae77f74 ee3e6606 00000005 eb667980 eb925000 eae77fc0
ee3d4cae <BR>Feb 11 03:16:10 Call Trace:<BR>Feb 11 03:16:10
[<c0105401>] show_stack_log_lvl+0xa1/0xe0<BR>Feb 11 03:16:10
[<c01055f1>] show_registers+0x181/0x200<BR>Feb 11 03:16:10
[<c0105810>] die+0x100/0x1a0<BR>Feb 11 03:16:10 [<c01156f6>]
do_page_fault+0x3c6/0x8b1<BR>Feb 11 03:16:10 [<c0105067>]
error_code+0x2b/0x30<BR>Feb 11 03:16:10 [<ee3e2080>]
w_update_odbm+0x100/0x220 [drbd]<BR>Feb 11 03:16:10 [<ee3d4cae>]
drbd_worker+0x2de/0x4b5 [drbd]<BR>Feb 11 03:16:10 [<ee3e70fc>]
drbd_thread_setup+0x8c/0x100 [drbd]<BR>Feb 11 03:16:10 [<c0102e95>]
kernel_thread_helper+0x5/0x10<BR>Feb 11 03:16:10 Code: 89 c8 5b 5d c3 8d 74 26
00 8d bc 27 00 00 00 00 55 89 e5 57 56 89 c6 53 83 ec 28 89 55 e8 c7 45 ec 00 00
00 00 89 55 f0 8b 40 14 <8b> 50 10 8b 48 14 01 55 e8 11 4d ec 8b 40 54 c7
45 e0 00 00 00 <BR>Feb 11 03:16:10 <0>Fatal exception: panic in 5
seconds</FONT><BR></SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=800325117-14022007>Thanks,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=800325117-14022007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=800325117-14022007>EM--</DIV></SPAN></FONT></BODY></HTML>