Hello, I just want to check if somebody saw this message: We did: hp_rescan, and this initialized multipath to create new mpath devices for new luns and we got: Feb 10 04:33:26 b021ple0 kernel: Unable to handle kernel NULL pointer dereference at 0000000000000030 RIP: Feb 10 04:33:26 b021ple0 kernel: <ffffffff8810d34d>{:dm_mod:__map_bio+69} Feb 10 04:33:26 b021ple0 kernel: PGD 3798e1067 PUD 350556067 PMD 0 Feb 10 04:33:26 b021ple0 kernel: Oops: 0000 [1] SMP Feb 10 04:33:26 b021ple0 kernel: last sysfs file: /block/dm-0/uevent Feb 10 04:33:26 b021ple0 kernel: CPU 6 Feb 10 04:33:26 b021ple0 kernel: Modules linked in: nfs mptctl mptbase softdog ipmi_si ipmi_devintf ipmi_msghandler nfsd exportfs lockd nfs_acl hpilo sunrpc bonding ipv6 dock button battery ac apparmor ext3 jbd loop dm_round_robin dm_multipath scsi_dh usbhid reiserfs dm_snapshot usb_storage sata_nv libata generic ide_cd cdrom e1000 st bnx2 shpchp pci_hotplug ohci_hcd uhci_hcd ehci_hcd usbcore serio_raw pcmcia pcmcia_core edd dm_mod fan thermal processor sg qla2xxx firmware_class scsi_transport_fc cciss amd74xx sd_mod scsi_mod ide_disk ide_core Feb 10 04:33:26 b021ple0 kernel: Pid: 24485, comm: multipathd Tainted: G U 2.6.16.60-0.66.1-smp #1 Feb 10 04:33:26 b021ple0 kernel: RIP: 0010:[<ffffffff8810d34d>] <ffffffff8810d34d>{:dm_mod:__map_bio+69} Feb 10 04:33:26 b021ple0 kernel: RSP: 0000:ffff8101167a1c18 EFLAGS: 00010202 Feb 10 04:33:26 b021ple0 kernel: RAX: 0000000000000000 RBX: 0000000021b61740 RCX: 0000000000000000 Feb 10 04:33:26 b021ple0 kernel: RDX: ffff8108ca288400 RSI: ffff810340e2a640 RDI: ffffc2000391f0e0 Feb 10 04:33:26 b021ple0 kernel: RBP: ffff810340e2a640 R08: ffff810774568b40 R09: ffff81046d4fe600 Feb 10 04:33:26 b021ple0 kernel: R10: 0000000000000002 R11: 0000000000000001 R12: ffff8108ca2883f0 Feb 10 04:33:26 b021ple0 kernel: R13: ffff8107e7568c00 R14: 0000000000000000 R15: ffffffff88110e9d Feb 10 04:33:26 b021ple0 kernel: FS: 00002b755522d1c0(0000) GS:ffff810b71c2dec0(0000) knlGS:00000000df53dba0 Feb 10 04:33:26 b021ple0 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b Feb 10 04:33:26 b021ple0 kernel: CR2: 0000000000000030 CR3: 0000000190c26000 CR4: 00000000000006e0 Feb 10 04:33:26 b021ple0 kernel: Process multipathd (pid: 24485, threadinfo ffff8101167a0000, task ffff81069384e040) Feb 10 04:33:26 b021ple0 kernel: Stack: ffffffffde49e8c0 ffff810774568b40 ffff81046ffa2200 ffffffffde49e8c0 Feb 10 04:33:26 b021ple0 kernel: ffff810774568b40 ffffffff8810ddfe 0000000000000000 ffffffff80118335 Feb 10 04:33:26 b021ple0 kernel: ffff8108ca2883f0 ffffc2000391f0e0 Feb 10 04:33:26 b021ple0 kernel: Call Trace: <ffffffff8810ddfe>{:dm_mod:__split_bio+408} Feb 10 04:33:26 b021ple0 kernel: <ffffffff80118335>{smp_call_function+50} <ffffffff88110e9d>{:dm_mod:dev_suspend+0} Feb 10 04:33:26 b021ple0 kernel: <ffffffff8810e067>{:dm_mod:__flush_deferred_io+31} <ffffffff8810e664>{:dm_mod:dm_resume+160} Feb 10 04:33:26 b021ple0 kernel: <ffffffff88110feb>{:dm_mod:dev_suspend+334} <ffffffff88111801>{:dm_mod:ctl_ioctl+567} Feb 10 04:33:26 b021ple0 kernel: <ffffffff80199105>{do_ioctl+85} <ffffffff80199363>{vfs_ioctl+584} Feb 10 04:33:26 b021ple0 kernel: <ffffffff801993dd>{sys_ioctl+100} <ffffffff8010ae36>{system_call+126} Feb 10 04:33:26 b021ple0 kernel: Feb 10 04:33:26 b021ple0 kernel: Code: ff 50 30 83 f8 00 89 c6 7e 73 48 8b 45 10 48 8b 80 98 00 00 Feb 10 04:33:26 b021ple0 kernel: RIP <ffffffff8810d34d>{:dm_mod:__map_bio+69} RSP <ffff8101167a1c18> Feb 10 04:33:26 b021ple0 kernel: CR2: 0000000000000030 I found that the error is in dm_mod Code starting with the faulting instruction =========================================== 0: ff 50 30 callq *0x30(%rax) <= in this function 3: 83 f8 00 cmp $0x0,%eax 6: 89 c6 mov %eax,%esi 8: 7e 73 jle 0x7d a: 48 8b 45 10 mov 0x10(%rbp),%rax e: 48 rex.W f: 8b .byte 0x8b 10: 80 .byte 0x80 11: 98 cwtl And it directs me to 0x34d is in __map_bio (drivers/md/dm.c:559). 554 * anything, the target has assumed ownership of 555 * this io. 556 */ 557 atomic_inc(&tio->io->io_count); 558 sector = clone->bi_sector; 559 r = ti->type->map(ti, clone, &tio->info); <==== to this line 560 if (r > 0) { 561 /* the bio has been remapped so dispatch it */ 562 blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, 563 tio->io->bio->bi_bdev->bd_dev, sector, After this the multipathd was in state <defunc> Best regards Jozef -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel