http://bugzilla.kernel.org/show_bug.cgi?id=12020 Summary: scsi_times_out NULL pointer dereference Product: SCSI Drivers Version: 2.5 KernelVersion: 2.6.28-git20081113 Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Other AssignedTo: scsi_drivers-other@xxxxxxxxxxxxxxxxxxxx ReportedBy: bs@xxxxxxxxx Latest working kernel version: 2.6.27 Earliest failing kernel version: 2.6.28-rc4 Hardware Environment: Infortrend G2430 connected to LSI22320R Problem Description: Hello, first in 2.6.28-rc{1,2,3} the error handler was entirely broken - it deadlocked. In rc4 this is fixed, but now I already two times got a Null pointer dereference while doing some error handler tests. All of that looks like due to the scsi timeout commits. Steps to reproduce: E.g. reset devices connected to LSI 53C1030 devices using lsiutil. Can be reproduced on about 20% eh activations. (gdb) l *(scsi_times_out+0x15) 0xffffffff80460f1e is in scsi_times_out (drivers/scsi/scsi_error.c:176). 171 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *); 172 enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED; 173 174 scsi_log_completion(scmd, TIMEOUT_ERROR); 175 176 if (scmd->device->host->transportt->eh_timed_out) 177 eh_timed_out = scmd->device->host->transportt->eh_timed_out; 178 else if (scmd->device->host->hostt->eh_timed_out) 179 eh_timed_out = scmd->device->host->hostt->eh_timed_out; 180 else [ 143.804672] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 [ 143.808507] IP: [<ffffffff80460f1e>] scsi_times_out+0x15/0x71 [ 143.816020] PGD f9381067 PUD f9360067 PMD 0 [ 143.824018] Oops: 0000 [#1] SMP [ 143.824018] last sysfs file: /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_map [ 143.832016] Dumping ftrace buffer: [ 143.832016] (ftrace buffer empty) [ 143.832016] CPU 1 [ 143.832016] Modules linked in: mptctl ib_ipoib inet_lro ib_umad rdma_ucm rdma_cm ib_cm iw_cm ib_sa ib_addr ib_uvee [ 143.832016] Pid: 246, comm: pdflush Not tainted 2.6.28-rc4-bs1 #10 [ 143.832016] RIP: 0010:[<ffffffff80460f1e>] [<ffffffff80460f1e>] scsi_times_out+0x15/0x71 [ 143.832016] RSP: 0018:ffff88007f6a3df0 EFLAGS: 00010086 [ 143.832016] RAX: ffff88007ebf5330 RBX: 0000000000000000 RCX: ffff8800f93804b8 [ 143.832016] RDX: ffff88007ebf5948 RSI: 0000000000000246 RDI: ffff8800f9380378 [ 143.832016] RBP: ffff88007f6a3e00 R08: 0000000000000000 R09: 0000000000000000 [ 143.832016] R10: ffff8800f9144680 R11: ffff88007eeac240 R12: ffff88007ebf5330 [ 143.832016] R13: ffff88007ebf5808 R14: ffffffff80380461 R15: 0000000000000000 [ 143.832016] FS: 0000000000733860(0000) GS:ffff8800fb29ab40(0000) knlGS:0000000000000000 [ 143.832016] CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b [ 143.832016] CR2: 0000000000000000 CR3: 00000000e80ec000 CR4: 00000000000006e0 [ 143.832016] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 143.832016] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 143.832016] Process pdflush (pid: 246, threadinfo ffff88007ed12000, task ffff88007ed11890) [ 143.832016] Stack: [ 143.832016] ffff88007f6a3e00 ffff8800f9380378 ffff88007f6a3e20 ffffffff80380426 [ 143.832016] ffff88007ebf5330 ffff8800f9380378 ffff88007f6a3e70 ffffffff803804f9 [ 143.832016] ffff88007eea0000 ffff88007ebf5668 0000000000000246 ffff88007ebf5330 [ 143.832016] Call Trace: [ 143.832016] <IRQ> <0> [<ffffffff80380426>] blk_rq_timed_out+0x1b/0x56 [ 143.832016] [<ffffffff803804f9>] blk_rq_timed_out_timer+0x98/0x118 [ 143.832016] [<ffffffff80380461>] ? blk_rq_timed_out_timer+0x0/0x118 [ 143.832016] [<ffffffff802464e2>] run_timer_softirq+0x14c/0x1cc [ 143.832016] [<ffffffff80242392>] __do_softirq+0x83/0x128 [ 143.832016] [<ffffffff8020d03c>] call_softirq+0x1c/0x28 [ 143.832016] [<ffffffff8020ea39>] do_softirq+0x49/0x90 [ 143.832016] [<ffffffff802422aa>] irq_exit+0x44/0x46 [ 143.832016] [<ffffffff8020e88b>] do_IRQ+0xba/0xcf -- Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html