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<DIV><FONT color=#000000 size=2 face=Arial>Hello All,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT color=#000000 size=2 face=Arial>I have a RAID storage box connected to a Linux server through fc cables. The server is using <BR>kernel 2.6.26, and multipath-tools v0.4.7 (with dm-mpath target version 1.0.5) is installed on it <BR>to handle the disk scsi devices from the storage box. The multipath device is mounted and <BR>used for a file system. </FONT></DIV>
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<DIV><FONT color=#000000 size=2 face=Arial>When fc port is down, it is seen that the scsi fc transport layer removes the corresponding <BR>fc-target and all the scsi device attached to this target. And when the fc port come back up, <BR>I see the kernel crash. Below are the details on the crash. Is there any patch available to fix <BR>this crash?</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT color=#000000 size=2 face=Arial>During port down the output of multipath -l <BR>===============================================</FONT></DIV>
<DIV><FONT color=#000000 size=2 face=Arial>/ > multipath -l<BR>22230000155f989c9 dm-0 ,<BR>[size=70G][features=0][hwhandler=1 alua][rw]<BR>\_ round-robin 0 [prio=0][enabled]<BR> \_ #:#:#:# - #:# [failed][undef]<BR> \_ #:#:#:# - #:# [failed][undef]<BR> \_ #:#:#:# - #:# [failed][undef]<BR> \_ #:#:#:# - #:# [failed][undef]<BR>22207000155f84ba3 dm-1 ,<BR>[size=70G][features=0][hwhandler=1 alua][rw]<BR>\_ round-robin 0 [prio=0][enabled]<BR> \_ #:#:#:# - #:# [failed][undef]<BR> \_ #:#:#:# - #:# [failed][undef]<BR>/ ></FONT></DIV><FONT color=#000000 size=2 face=Arial>
<DIV><BR>During port up I am getting below stack dump in Linux server<BR>=============================================</DIV>
<DIV>kobject_add_internal failed for 4:0:3:0 with -EEXIST, don't try to register things with the same name in the same directory.<BR>Pid: 1384, comm: scsi_wq_4 Tainted: P 2.6.26EIGHTSTACK_64_V15_V11_8GB_SANFS_UP #1</DIV>
<DIV>Call Trace:<BR> [<ffffffff80334455>] kobject_add_internal+0x11e/0x15d<BR> [<ffffffff803348b3>] kobject_add+0x74/0x7c<BR> [<ffffffff80283df4>] bio_alloc_bioset+0x89/0xd9<BR> [<ffffffff802846a9>] bio_map_kern+0xae/0x103<BR> [<ffffffff803280c9>] __freed_request+0x2f/0x7f<BR> [<ffffffff8032813d>] freed_request+0x24/0x44<BR> [<ffffffff80334332>] kobject_get+0x12/0x17<BR> [<ffffffff80393f2f>] get_device+0x17/0x1f<BR> [<ffffffff8039450a>] device_add+0x82/0x519<BR> [<ffffffff803c300e>] scsi_sysfs_add_sdev+0x86/0x1d5<BR> [<ffffffff803c140d>] scsi_probe_and_add_lun+0x77b/0x89f<BR> [<ffffffff803c1a60>] __scsi_scan_target+0x3d0/0x566<BR> [<ffffffff80221989>] update_curr+0x54/0x64<BR> [<ffffffff80221989>] update_curr+0x54/0x64<BR> [<ffffffff803c208f>] scsi_scan_target+0x96/0xb9<BR> [<ffffffff803c6064>] fc_scsi_scan_rport+0x70/0x84<BR> [<ffffffff803c5ff4>] fc_scsi_scan_rport+0x0/0x84<BR> [<ffffffff80233c95>] run_workqueue+0x74/0xee<BR> [<ffffffff8023431b>] worker_thread+0xd0/0xdb<BR> [<ffffffff802367e4>] autoremove_wake_function+0x0/0x2e<BR> [<ffffffff8023424b>] worker_thread+0x0/0xdb<BR> [<ffffffff8023669c>] kthread+0x47/0x73<BR> [<ffffffff802247b3>] schedule_tail+0x18/0x4c<BR> [<ffffffff8020c5b8>] child_rip+0xa/0x12<BR> [<ffffffff80236655>] kthread+0x0/0x73<BR> [<ffffffff8020c5ae>] child_rip+0x0/0x12</DIV>
<DIV><BR>After fc port up and down for one or two time I am getting below crash in Linux server<BR>===============================================================</DIV>
<DIV>BUG: unable to handle kernel NULL pointer dereference at 0000000000000028<BR>IP: [<ffffffff802a6ef5>] sysfs_find_dirent+0x9/0x2f<BR>PGD 21101067 PUD 210d0067 PMD 0 <BR>Oops: 0000 [1] <BR>Firmware Version : 01.01.0000.00</DIV>
<DIV>Pid: 1385, comm: fc_wq_4 2.6.26EIGHTSTACK_64_V15_V11_8GB_SANFS_UP #1<BR> [ffffffff802a6ef5] sysfs_find_dirent+0x9/0x2f<BR>RIP: 0010:[ffffffff802a6ef5] RSP: 0018:ffff8100240cdd30 EFLAGS: 00010286<BR>RAX: ffff810020c14c30 RBX: ffffffff805c1d8e RCX: 0000000000000002<BR>RDX: ffff8100329a8278 RSI: ffffffff805c1d8e RDI: 0000000000000000<BR>RBP: ffffffff805c1d8e R08: 00000000000015c1 R09: ffff81003f818150<BR>R10: 0000000000000000 R11: ffff8100240d3f50 R12: 0000000000000000<BR>R13: ffff810022031c08 R14: ffffffff806ac6a0 R15: 00000000016a5018</DIV>
<DIV>Call Trace<BR>--------------------<BR> [ffffffff802a7914] ? sysfs_get_dirent+0x24/0x58<BR> [ffffffff802a81c2] ? sysfs_remove_group+0x24/0xc0<BR> [ffffffff80398a51] ? device_pm_remove+0x18/0x49<BR> [ffffffff803942e3] ? device_del+0x13/0x15b<BR> [ffffffff80394434] ? device_unregister+0x9/0x12<BR> [ffffffff803c2e0a] ? __scsi_remove_device+0x2a/0x7a<BR> [ffffffff803c2e7b] ? scsi_remove_device+0x21/0x2e<BR> [ffffffff803c2f62] ? __remove_child+0x0/0x1a</DIV>
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<DIV>Thanks,<BR>Praveen</FONT></DIV></BODY></HTML>