Hi all, (I am not sure if this is the right address for this bug, but dm_* is the first function listed in trace) this happened when I tried dd-ing LV, which resides on RAID10 sw storage, to network via netcat. The actual user-visible manifestation was segfault of dd that was used for reading. On first request the error reported was "unable to handle kernel NULL pointer dereference...", but on subsequent tries this changed to "general protection fault", see below. HW is a bit dated, but had no problems with it up to now, and SW raid is used here. Kernel was 4.2.4. Is this the right mlist for such bug? Tnx, b. 2015-11-10T02:03:26+00:00 ring kernel: [1251477.590992] BUG: unable to handle kernel NULL pointer dereference at 00000000000004f0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.591361] IP: [<ffffffff818637c6>] dm_any_congested+0x26/0x50 2015-11-10T02:03:26+00:00 ring kernel: [1251477.591565] PGD 1afdc6067 PUD 5106e8067 PMD 0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.591827] Oops: 0000 [#1] SMP 2015-11-10T02:03:26+00:00 ring kernel: [1251477.592057] CPU: 2 PID: 4277 Comm: dd Tainted: G W 4.2.4 #1 2015-11-10T02:03:26+00:00 ring kernel: [1251477.592226] Hardware name: HP ProLiant DL360 G5, BIOS P58 04/26/2010 2015-11-10T02:03:26+00:00 ring kernel: [1251477.592392] task: ffff88080b41a400 ti: ffff8800caae8000 task.ti: ffff8800caae8000 2015-11-10T02:03:26+00:00 ring kernel: [1251477.592682] RIP: 0010:[<ffffffff818637c6>] [<ffffffff818637c6>] dm_any_congested+0x26/0x50 2015-11-10T02:03:26+00:00 ring kernel: [1251477.593007] RSP: 0018:ffff8800caaebcf0 EFLAGS: 00010206 2015-11-10T02:03:26+00:00 ring kernel: [1251477.593175] RAX: 0000000000000002 RBX: ffff88080ac30770 RCX: 6b7369440f000000 2015-11-10T02:03:26+00:00 ring kernel: [1251477.593465] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff880805a34800 2015-11-10T02:03:26+00:00 ring kernel: [1251477.593753] RBP: ffff8800caaebd28 R08: 0000000000000100 R09: 0000000000000100 2015-11-10T02:03:26+00:00 ring kernel: [1251477.594041] R10: 0000000000000200 R11: ffff8800caaebcf0 R12: 0000000000000000 2015-11-10T02:03:26+00:00 ring kernel: [1251477.594331] R13: ffff88001b7b0d00 R14: ffffea00138c6340 R15: ffff8800caaebe80 2015-11-10T02:03:26+00:00 ring kernel: [1251477.594621] FS: 00007f1f99c91740(0000) GS:ffff88082fa80000(0000) knlGS:0000000000000000 2015-11-10T02:03:26+00:00 ring kernel: [1251477.594911] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b 2015-11-10T02:03:26+00:00 ring kernel: [1251477.595076] CR2: 00000000000004f0 CR3: 00000002254cb000 CR4: 00000000000026e0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.595365] Stack: 2015-11-10T02:03:26+00:00 ring kernel: [1251477.595524] ffffffff81200798 ffff8800caaebd18 ffffffff8116a18e 0000000000000000 2015-11-10T02:03:26+00:00 ring kernel: [1251477.595943] ffff88001b7b0da0 ffff88080ac308d8 ffff88001b7b0d00 ffff8800caaebd68 2015-11-10T02:03:26+00:00 ring kernel: [1251477.596362] ffffffff8117629e 0000000000000292 0000000000000100 0000000000000100 2015-11-10T02:03:26+00:00 ring kernel: [1251477.596784] Call Trace: 2015-11-10T02:03:26+00:00 ring kernel: [1251477.596947] [<ffffffff81200798>] ? inode_congested+0x58/0x120 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597115] [<ffffffff8116a18e>] ? find_get_entry+0x1e/0x80 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597282] [<ffffffff8117629e>] page_cache_async_readahead+0x4e/0x70 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597450] [<ffffffff8116b211>] generic_file_read_iter+0x391/0x5b0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597617] [<ffffffff8120c677>] blkdev_read_iter+0x37/0x40 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597784] [<ffffffff811d7757>] __vfs_read+0xa7/0xd0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.597949] [<ffffffff811d7802>] vfs_read+0x82/0x130 2015-11-10T02:03:26+00:00 ring kernel: [1251477.598114] [<ffffffff811d7c76>] SyS_read+0x46/0xb0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.598280] [<ffffffff81a7556e>] entry_SYSCALL_64_fastpath+0x12/0x71 2015-11-10T02:03:26+00:00 ring kernel: [1251477.598446] Code: 80 00 00 00 00 66 66 66 66 90 48 8b 97 28 01 00 00 89 f0 83 e2 01 75 38 48 8b 8f e8 00 00 00 48 85 c9 74 1c 48 8b 97 30 01 00 00 <48> 8b b2 f0 04 00 00 f7 c6 00 08 00 00 74 07 23 82 d0 01 00 00 2015-11-10T02:03:26+00:00 ring kernel: [1251477.600930] RIP [<ffffffff818637c6>] dm_any_congested+0x26/0x50 2015-11-10T02:03:26+00:00 ring kernel: [1251477.600930] RSP <ffff8800caaebcf0> 2015-11-10T02:03:26+00:00 ring kernel: [1251477.600930] CR2: 00000000000004f0 2015-11-10T02:03:26+00:00 ring kernel: [1251477.601561] ---[ end trace 17914a53c55dd503 ]--- Second and subsequent: 2015-11-10T02:04:46+00:00 ring kernel: [1251557.440486] general protection fault: 0000 [#2] SMP 2015-11-10T02:04:46+00:00 ring kernel: [1251557.440732] CPU: 7 PID: 4806 Comm: dd Tainted: G D W 4.2.4 #1 2015-11-10T02:04:46+00:00 ring kernel: [1251557.440904] Hardware name: HP ProLiant DL360 G5, BIOS P58 04/26/2010 2015-11-10T02:04:46+00:00 ring kernel: [1251557.441071] task: ffff88019b6c9800 ti: ffff88062c96c000 task.ti: ffff88062c96c000 2015-11-10T02:04:46+00:00 ring kernel: [1251557.441369] RIP: 0010:[<ffffffff818637c6>] [<ffffffff818637c6>] dm_any_congested+0x26/0x50 2015-11-10T02:04:46+00:00 ring kernel: [1251557.441699] RSP: 0018:ffff88062c96fcf0 EFLAGS: 00010206 2015-11-10T02:04:46+00:00 ring kernel: [1251557.441863] RAX: 0000000000000002 RBX: ffff88080ac30770 RCX: 6566667542207972 2015-11-10T02:04:46+00:00 ring kernel: [1251557.442152] RDX: 1b0a1bbb00007972 RSI: 0000000000000002 RDI: ffff880805a34800 2015-11-10T02:04:46+00:00 ring kernel: [1251557.442445] RBP: ffff88062c96fd28 R08: 0000000000000100 R09: 0000000000000100 2015-11-10T02:04:46+00:00 ring kernel: [1251557.442733] R10: 0000000000000200 R11: ffff88062c96fcf0 R12: 0000000000000000 2015-11-10T02:04:46+00:00 ring kernel: [1251557.443021] R13: ffff88080587ec00 R14: ffffea001699af40 R15: ffff88062c96fe80 2015-11-10T02:04:46+00:00 ring kernel: [1251557.443310] FS: 00007f0dc3de2740(0000) GS:ffff88082fbc0000(0000) knlGS:0000000000000000 2015-11-10T02:04:46+00:00 ring kernel: [1251557.443603] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b 2015-11-10T02:04:46+00:00 ring kernel: [1251557.443768] CR2: 00000000b768a0a0 CR3: 00000000cab12000 CR4: 00000000000026e0 2015-11-10T02:04:46+00:00 ring kernel: [1251557.447111] Stack: 2015-11-10T02:04:46+00:00 ring kernel: [1251557.447269] ffffffff81200798 ffff88062c96fd18 ffffffff8116a18e 0000000000000000 2015-11-10T02:04:46+00:00 ring kernel: [1251557.447688] ffff88080587eca0 ffff88080ac308d8 ffff88080587ec00 ffff88062c96fd68 2015-11-10T02:04:46+00:00 ring kernel: [1251557.448109] ffffffff8117629e 0000000000000001 0000000000000100 0000000000000100 2015-11-10T02:04:46+00:00 ring kernel: [1251557.448528] Call Trace: 2015-11-10T02:04:46+00:00 ring kernel: [1251557.448691] [<ffffffff81200798>] ? inode_congested+0x58/0x120 2015-11-10T02:04:46+00:00 ring kernel: [1251557.448859] [<ffffffff8116a18e>] ? find_get_entry+0x1e/0x80 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449028] [<ffffffff8117629e>] page_cache_async_readahead+0x4e/0x70 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449195] [<ffffffff8116b211>] generic_file_read_iter+0x391/0x5b0 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449362] [<ffffffff8120c677>] blkdev_read_iter+0x37/0x40 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449530] [<ffffffff811d7757>] __vfs_read+0xa7/0xd0 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449695] [<ffffffff811d7802>] vfs_read+0x82/0x130 2015-11-10T02:04:46+00:00 ring kernel: [1251557.449859] [<ffffffff811d7c76>] SyS_read+0x46/0xb0 2015-11-10T02:04:46+00:00 ring kernel: [1251557.450030] [<ffffffff81a7556e>] entry_SYSCALL_64_fastpath+0x12/0x71 2015-11-10T02:04:46+00:00 ring kernel: [1251557.450197] Code: 80 00 00 00 00 66 66 66 66 90 48 8b 97 28 01 00 00 89 f0 83 e2 01 75 38 48 8b 8f e8 00 00 00 48 85 c9 74 1c 48 8b 97 30 01 00 00 <48> 8b b2 f0 04 00 00 f7 c6 00 08 00 00 74 07 23 82 d0 01 00 00 2015-11-10T02:04:46+00:00 ring kernel: [1251557.450465] RIP [<ffffffff818637c6>] dm_any_congested+0x26/0x50 2015-11-10T02:04:46+00:00 ring kernel: [1251557.450465] RSP <ffff88062c96fcf0> 2015-11-10T02:04:46+00:00 ring kernel: [1251557.453232] ---[ end trace 17914a53c55dd504 ]--- -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
