Michael Krolikowski wrote: > I've first seen the bug in Debian Lenny with Debian's patched Linux 2.6. > Now I've just installed Linux 2.6.26.8 (UML) and seen a different > behavior: > > SCTP: Hash tables configured (established 512 bind 512) > BUG: soft lockup - CPU#0 stuck for 61s! [sctp_test:847] > Modules linked in: sctp > > Modules linked in: sctp > Pid: 847, comm: sctp_test Not tainted 2.6.26.8 > RIP: 0033:[<0000000062dad9c2>] > RSP: 0000000061f3b870 EFLAGS: 00000202 > RAX: 7360adde2c000001 RBX: 0000000061e20000 RCX: 0000000061f3b910 > RDX: 7360adde2c000001 RSI: 0000000000000000 RDI: 000000006150ea00 > RBP: 0000000061f3b880 R08: 0000000061e20140 R09: 0000000000000000 > R10: 0000000060228240 R11: 0000000000000049 R12: 0000000061e20000 > R13: 0000000061e20000 R14: 0000000062dbfeb5 R15: 0000000062dc1a00 > Call Trace: > 601c7ae8: [<6004e355>] softlockup_tick+0xf7/0x10a > 601c7af8: [<600318e7>] raise_softirq+0x64/0x6d > 601c7b28: [<60035bf0>] run_local_timers+0x18/0x1a > 601c7b38: [<60035c69>] update_process_times+0x2e/0x59 > 601c7b68: [<600463c9>] tick_sched_timer+0x64/0x96 > 601c7b98: [<600418da>] __run_hrtimer+0x26/0x6f > 601c7bb8: [<600421b2>] hrtimer_interrupt+0xe3/0x143 > 601c7bf8: [<60012cd4>] um_timer+0xf/0x16 > 601c7c08: [<6004e78a>] handle_IRQ_event+0x2b/0x5f > 601c7c38: [<6004e81f>] __do_IRQ+0x61/0xa6 > 601c7c68: [<60010b8a>] do_IRQ+0x23/0x39 > 601c7c88: [<60012d42>] timer_handler+0x21/0x2f > 601c7ca8: [<60020e87>] real_alarm_handler+0x3f/0x41 > 601c7cb8: [<62dbfeb5>] sctp_pname+0x0/0x1a [sctp] > 601c7d30: [<62dad9c2>] sctp_assoc_update_retran_path+0x44/0x13e [sctp] > 601c7db8: [<60020ee5>] alarm_handler+0x2e/0x39 > 601c7dd8: [<60021179>] handle_signal+0x6b/0xa1 > 601c7e10: [<62dbfeb5>] sctp_pname+0x0/0x1a [sctp] > 601c7e28: [<60022a90>] hard_handler+0x10/0x14 > 601c7e98: [<62dbfeb5>] sctp_pname+0x0/0x1a [sctp] > 601c7ee8: [<62dad9c2>] sctp_assoc_update_retran_path+0x44/0x13e [sctp] > > I did the test with the sctp_test tool from http://lksctp.sf.net/ > I just repeated executing the tool manually, so no tight loop. Can you provide the command line args you use? Want to try it in my KVM sessions. -vlad > I always had both systems running with the same Linux Version. But this > shouldn't be the problem should it? It's always the same ICMP message I > get > from the remote host. > I did the test with Debian Lenny running inside VMware as well but > didn't > test inside KVM. I couldn't reproduce the bug in live systems but I did > only one quick test there. I'll give that a try and let you know - but > it > might take me a while. > > Michael > > > -----Original Message----- > From: Vlad Yasevich [mailto:vladislav.yasevich@xxxxxx] > Sent: Mittwoch, 30. September 2009 16:31 > To: Michael Krolikowski > Cc: linux-sctp@xxxxxxxxxxxxxxx > Subject: Re: linux sctp bug > > Michael Krolikowski wrote: >> Hi, >> >> I'm testing it using two UML machines. Both of them running Linux >> 2.6.31. >> I tried it today again and it seems that the error occurs not as I > first >> said after only a few tries but many tries later it does. >> I also tried with 2.6.31.1 (UML) with the same results. >> I used Debian Lenny with a 2.6.26 Linux where I got the error for the >> first time. > > So you were able to reproduce this with 2.6.26 kernel? > > How do you test? Do you just try to call connect() in a loop? > > I run under KVM with a connect() call in a tight loop and see > not issues. My ICMP sender is an Ubuntu Jaunty (2.6.28-15-generic) > kernel. > > Looking at the stack trace you posted, the failure happens here: > if (!asoc->temp) { >>>> list_del(&asoc->asocs); > > The addresses look very weird to. > > Can reproduce this with live systems, or KVM? I am suspecting UML... > > -vlad > > >> I hope this little information helps you a bit. >> >> >> Regards, >> >> Michael >> >> >> -----Original Message----- >> From: Vlad Yasevich [mailto:vladislav.yasevich@xxxxxx] >> Sent: Montag, 28. September 2009 18:46 >> To: Michael Krolikowski >> Cc: Sridhar Samudrala; Linux SCTP Dev Mailing list >> Subject: Re: linux sctp bug >> >> Michael Krolikowski wrote: >>> Hi, >>> >>> I think I found a bug in the Linux SCTP implementation. I hope you > are >>> the right persons to ask for help with this. >> The right place to ask is on linux-sctp mailing list. >> >>> If I send an SCTP INIT to a host which does not support SCTP (e.g. > the >>> module is not loaded), the >>> other host sends an ICMP Protocol unreachable. This makes the SCTP >>> module on the initiating host >>> crash. It maybe that it crashes not at the first try but if I repeat >> the >>> SCTP INIT 3-4 times it will crash. >> Hm.. I've tried to reproduce and couldn't with top of tree 2.6.31. >> I've tried repeating INITs over the same path and over multiple paths, >> but >> didn't see a crash. >> >> Would you be able to do a bisect? >> >> Thanks >> -vlad >> >>> See this message: >>> SCTP: Hash tables configured (established 512 bind 512) >>> >>> Modules linked in: sctp >>> Pid: 610, comm: sctp_test Not tainted 2.6.31 >>> RIP: 0033:[<00000000646228f9>] >>> RSP: 0000000063873810 EFLAGS: 00010246 >>> RAX: 0000000000200200 RBX: 0000000063a20000 RCX: 00000000638e6800 >>> RDX: 0000000000100100 RSI: 000000006384b8c0 RDI: 0000000063a20000 >>> RBP: 0000000063873830 R08: 0000003000000008 R09: 0000000000000000 >>> R10: 000000000000000f R11: 0000000000000000 R12: 00000000ffffffea >>> R13: 00000000638e6800 R14: 0000000063a20000 R15: 0000000063a20000 >>> Call Trace: >>> 601f1ad8: [<60014bcd>] segv+0x1fd/0x20f >>> 601f1b18: [<601102f0>] process_backlog+0x8b/0xa9 >>> 601f1b58: [<60110904>] net_rx_action+0xe5/0x123 >>> 601f1bb8: [<60014c92>] segv_handler+0xb3/0xb9 >>> 601f1bf8: [<600329c4>] do_softirq+0x43/0x4a >>> 601f1c28: [<60016439>] free_irqs+0x72/0xd4 >>> 601f1c68: [<60012108>] sigio_handler+0x5a/0x5f >>> 601f1c88: [<60021a47>] sig_handler_common+0x87/0x9b >>> 601f1d10: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1d30: [<60017b51>] line_write_room+0x57/0x58 >>> 601f1db8: [<60021b90>] sig_handler+0x30/0x3b >>> 601f1dd8: [<60021de9>] handle_signal+0x6b/0xa1 >>> 601f1e28: [<600236fc>] hard_handler+0x10/0x14 >>> 601f1ee8: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> >>> Kernel panic - not syncing: Kernel mode fault at addr 0x100108, ip >>> 0x646228f9 >>> Call Trace: >>> 601f19d8: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f19e8: [<60158b8d>] panic+0xd3/0x174 >>> 601f1a20: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1a40: [<6004c462>] __module_text_address+0xd/0x5b >>> 601f1a58: [<6004c4b9>] is_module_text_address+0x9/0x11 >>> 601f1a68: [<6003e264>] __kernel_text_address+0x65/0x6b >>> 601f1a70: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1a88: [<60013a96>] show_trace+0x8e/0x92 >>> 601f1aa8: [<600271ff>] show_regs+0x2b/0x30 >>> 601f1ad8: [<60014bdf>] segv_handler+0x0/0xb9 >>> 601f1b18: [<601102f0>] process_backlog+0x8b/0xa9 >>> 601f1b58: [<60110904>] net_rx_action+0xe5/0x123 >>> 601f1bb8: [<60014c92>] segv_handler+0xb3/0xb9 >>> 601f1bf8: [<600329c4>] do_softirq+0x43/0x4a >>> 601f1c28: [<60016439>] free_irqs+0x72/0xd4 >>> 601f1c68: [<60012108>] sigio_handler+0x5a/0x5f >>> 601f1c88: [<60021a47>] sig_handler_common+0x87/0x9b >>> 601f1d10: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1d30: [<60017b51>] line_write_room+0x57/0x58 >>> 601f1db8: [<60021b90>] sig_handler+0x30/0x3b >>> 601f1dd8: [<60021de9>] handle_signal+0x6b/0xa1 >>> 601f1e28: [<600236fc>] hard_handler+0x10/0x14 >>> 601f1ee8: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> >>> >>> Modules linked in: sctp >>> Pid: 610, comm: sctp_test Not tainted 2.6.31 >>> RIP: 0033:[<00000000404ef5c0>] >>> RSP: 0000007fbf8613f8 EFLAGS: 00000246 >>> RAX: ffffffffffffffda RBX: 0000007fbf861460 RCX: ffffffffffffffff >>> RDX: 0000000000000100 RSI: 0000007fbf861410 RDI: 0000000000000003 >>> RBP: 0000000000000001 R08: 00000000ffffffff R09: 0000000000000000 >>> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000607560 >>> R13: 0000000000000002 R14: 0000000000000000 R15: 0000007fbf861450 >>> Call Trace: >>> 601f1960: [<6004c462>] __module_text_address+0xd/0x5b >>> 601f1978: [<60014e05>] panic_exit+0x2f/0x45 >>> 601f1998: [<60043417>] notifier_call_chain+0x33/0x5b >>> 601f19c8: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f19d8: [<60043459>] atomic_notifier_call_chain+0xf/0x11 >>> 601f19e8: [<60158b9e>] panic+0xe4/0x174 >>> 601f1a20: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1a40: [<6004c462>] __module_text_address+0xd/0x5b >>> 601f1a58: [<6004c4b9>] is_module_text_address+0x9/0x11 >>> 601f1a68: [<6003e264>] __kernel_text_address+0x65/0x6b >>> 601f1a70: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1a88: [<60013a96>] show_trace+0x8e/0x92 >>> 601f1aa8: [<600271ff>] show_regs+0x2b/0x30 >>> 601f1ad8: [<60014bdf>] segv_handler+0x0/0xb9 >>> 601f1b18: [<601102f0>] process_backlog+0x8b/0xa9 >>> 601f1b58: [<60110904>] net_rx_action+0xe5/0x123 >>> 601f1bb8: [<60014c92>] segv_handler+0xb3/0xb9 >>> 601f1bf8: [<600329c4>] do_softirq+0x43/0x4a >>> 601f1c28: [<60016439>] free_irqs+0x72/0xd4 >>> 601f1c68: [<60012108>] sigio_handler+0x5a/0x5f >>> 601f1c88: [<60021a47>] sig_handler_common+0x87/0x9b >>> 601f1d10: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> 601f1d30: [<60017b51>] line_write_room+0x57/0x58 >>> 601f1db8: [<60021b90>] sig_handler+0x30/0x3b >>> 601f1dd8: [<60021de9>] handle_signal+0x6b/0xa1 >>> 601f1e28: [<600236fc>] hard_handler+0x10/0x14 >>> 601f1ee8: [<646228f9>] sctp_association_free+0x2b/0x1e0 [sctp] >>> >>> This error seems only to occur if the remote host answers with ICMP >>> protocol unreachable. >>> If the remote host answers with SCTP ABORT, the error won't occur. >>> >>> >>> Thanks in advance, >>> >>> Michael Krolikowski >>> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-sctp" > in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-sctp" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html