Hello,<div><br></div><div>I have the following issue with DRBD 8.4. I have also reported it as a bug for the Ubuntu DRBD package, but after I did some more testing and used a manually compiled drbd kernel module and drbd-utils, the issue is still there. So it seems to be a generic DRBD thing.</div><div><br></div><div>When you use the same resource for 2 minors, it oops'es the kernel. Of course you should not do that, but on the other hand a kernel oops should not be the result. The expected output is just an error message, I think. This makes DRBD resource/minor management more difficult and also kind of dangerous.</div><div><br></div><div>DRBD 8.3 does not have this problem, probably because it works a bit different with resources/minors.</div><div><br></div><div>Steps to reproduce:</div><div>* drbdsetup new-resource test1</div><div>* drbdsetup new-minor test1 1 0</div><div>* drbdsetup new-minor test1 3 0</div><div><br></div><div>It exits showing the message 'Killed'. The kernel log shows some errors and DRBD is not usable anymore. After a short while or when executing other drbdsetup commands, the whole system crashes.</div><div><br></div><div>I am not sure whether it's the utils package, or the kernel module.</div><div><br></div><div>The system is running Ubuntu 14.04 with kernel package linux-image-3.13.0-24-generic. I have tested the Ubuntu packages for DRBD (DRBD 8.4.3 / drbd8-utils 2:8.4.4-1ubuntu1) and the manually compiled combination from drbd-8.4.5.tar.gz and drbd-utils-8.9.0.tar.gz.</div><div><br></div><div>This is the kernel output:</div><div><br></div><div>[ 75.396062] BUG: unable to handle kernel NULL pointer dereference at 0000000000000028</div><div>[ 75.397884] IP: [<ffffffff81351b38>] blk_throtl_drain+0x28/0x130</div><div>[ 75.399256] PGD dce0c067 PUD dce0b067 PMD 0 </div><div>[ 75.400025] Oops: 0000 [#1] SMP </div><div>[ 75.400025] Modules linked in: drbd(OF) libcrc32c bridge stp llc gpio_ich lpc_ich dm_multipath scsi_dh coretemp kvm_intel kvm serio_raw xgifb(C) lp parport i3200_edac mac_hid edac_core psmouse tg3 ptp pps_core 3w_9xxx</div><div>[ 75.400025] CPU: 0 PID: 1290 Comm: drbdsetup-84 Tainted: GF C O 3.13.0-24-generic #47-Ubuntu</div><div>[ 75.400025] Hardware name: ASUS RS120-E5/PA2/P5BV-R, BIOS 0203 10/19/2007</div><div>[ 75.400025] task: ffff880035c317f0 ti: ffff8800e7038000 task.ti: ffff8800e7038000</div><div>[ 75.400025] RIP: 0010:[<ffffffff81351b38>] [<ffffffff81351b38>] blk_throtl_drain+0x28/0x130</div><div>[ 75.400025] RSP: 0018:ffff8800e7039a88 EFLAGS: 00010046</div><div>[ 75.400025] RAX: 0000000000000000 RBX: ffff880105a7b510 RCX: 000000018010000f</div><div>[ 75.400025] RDX: 000000000000000e RSI: 0000000000000001 RDI: 0000000000000000</div><div>[ 75.400025] RBP: ffff8800e7039aa0 R08: 0000000000000000 R09: 0000000000000001</div><div>[ 75.400025] R10: ffffea00039ffb00 R11: ffffffff81340f10 R12: ffff880105a7b510</div><div>[ 75.400025] R13: ffff8800e9e88900 R14: ffff880105a7bb60 R15: 0000000000000003</div><div>[ 75.400025] FS: 00007f6220e82740(0000) GS:ffff88010fc00000(0000) knlGS:0000000000000000</div><div>[ 75.400025] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b</div><div>[ 75.400025] CR2: 0000000000000028 CR3: 00000000dce09000 CR4: 00000000000007f0</div><div>[ 75.400025] Stack:</div><div>[ 75.400025] ffff880105a7b510 0000000000000001 ffff880105a7bb70 ffff8800e7039ab0</div><div>[ 75.400025] ffffffff8134eb7e ffff8800e7039ae0 ffffffff81332c84 ffff880105a7b510</div><div>[ 75.400025] ffff8801097cbcf0 ffff880105a7bd10 ffff88010592d800 ffff8800e7039b08</div><div>[ 75.400025] Call Trace:</div><div>[ 75.400025] [<ffffffff8134eb7e>] blkcg_drain_queue+0xe/0x10</div><div>[ 75.400025] [<ffffffff81332c84>] __blk_drain_queue+0x74/0x180</div><div>[ 75.400025] [<ffffffff81332eed>] blk_cleanup_queue+0x8d/0x180</div><div>[ 75.400025] [<ffffffffa01a4d81>] drbd_create_device+0x471/0x780 [drbd]</div><div>[ 75.400025] [<ffffffff81385164>] ? __nla_reserve_nohdr+0x24/0x30</div><div>[ 75.400025] [<ffffffffa01a3fdb>] ? drbd_find_resource+0x3b/0x90 [drbd]</div><div>[ 75.400025] [<ffffffffa01adb37>] drbd_adm_new_minor+0x87/0xd0 [drbd]</div><div>[ 75.400025] [<ffffffff8164978d>] genl_family_rcv_msg+0x18d/0x370</div><div>[ 75.400025] [<ffffffff81649970>] ? genl_family_rcv_msg+0x370/0x370</div><div>[ 75.400025] [<ffffffff81649a01>] genl_rcv_msg+0x91/0xd0</div><div>[ 75.400025] [<ffffffff81647a89>] netlink_rcv_skb+0xa9/0xc0</div><div>[ 75.400025] [<ffffffff81647f88>] genl_rcv+0x28/0x40</div><div>[ 75.400025] [<ffffffff816470b5>] netlink_unicast+0xd5/0x1b0</div><div>[ 75.400025] [<ffffffff8164748f>] netlink_sendmsg+0x2ff/0x740</div><div>[ 75.400025] [<ffffffff816016fe>] sock_aio_write+0xfe/0x130</div><div>[ 75.400025] [<ffffffff8164664d>] ? netlink_insert+0x14d/0x240</div><div>[ 75.400025] [<ffffffff811b8daa>] do_sync_write+0x5a/0x90</div><div>[ 75.400025] [<ffffffff811b962d>] vfs_write+0x1ad/0x1f0</div><div>[ 75.400025] [<ffffffff811b9f69>] SyS_write+0x49/0xa0</div><div>[ 75.400025] [<ffffffff817266bf>] tracesys+0xe1/0xe6</div><div>[ 75.400025] Code: ff 66 90 66 66 66 66 90 55 48 89 e5 41 55 41 54 49 89 fc 53 4c 8b af 70 08 00 00 49 8b 85 a0 00 00 00 31 ff 48 8b 80 c8 05 00 00 <48> 8b 70 28 e8 9f 92 d9 ff 48 85 c0 48 89 c3 74 61 0f 1f 80 00 </div><div>[ 75.400025] RIP [<ffffffff81351b38>] blk_throtl_drain+0x28/0x130</div><div>[ 75.400025] RSP <ffff8800e7039a88></div><div>[ 75.400025] CR2: 0000000000000028</div><div>[ 75.400025] ---[ end trace f76955bc776ce5cd ]---</div><div><br></div><div>Met vriendelijke groet / Kind regards,<br>Dick Tump | Shock Media B.V.<br><br>Tel: +31 (0)546 - 714360<br>Fax: +31 (0)546 - 714361<br>Web: <a href="http://www.shockmedia.nl/">http://www.shockmedia.nl/</a><br><br>Connect to me @ LinkedIn:<br><a href="http://nl.linkedin.com/in/dicktump">http://nl.linkedin.com/in/dicktump</a></div>