I ran some additional tests and these traces may also be usefull. They appears before the soft-lockup are detected.
fermi:~# ping6 -c 500 -f 2007::1 PING 2007::1(2007::1) 56 data bytes . ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.25-rc1-00113-g69cc64d-dirty #34 ------------------------------------------------------- ping6/1058 is trying to acquire lock: (&tbl->lock){-+-+}, at: [<c02691ac>] neigh_lookup+0x43/0xa2 but task is already holding lock: (&n->lock){-+..}, at: [<c026b620>] neigh_timer_handler+0x16/0x252 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&n->lock){-+..}: [<c01330b8>] __lock_acquire+0x947/0xafc [<c026982c>] neigh_periodic_timer+0x99/0x142 [<c01332d0>] lock_acquire+0x63/0x80 [<c026982c>] neigh_periodic_timer+0x99/0x142 [<c02eba61>] _write_lock+0x19/0x28 [<c026982c>] neigh_periodic_timer+0x99/0x142 [<c026982c>] neigh_periodic_timer+0x99/0x142 [<c0120c90>] run_timer_softirq+0xfe/0x159 [<c0269793>] neigh_periodic_timer+0x0/0x142 [<c011dbfa>] __do_softirq+0x6f/0xe9 [<c011dcae>] do_softirq+0x3a/0x52 [<c011dfc3>] irq_exit+0x44/0x46 [<c010d680>] smp_apic_timer_interrupt+0x71/0x81 [<c0103747>] apic_timer_interrupt+0x33/0x38 [<c014e0ce>] mmap_region+0xe1/0x376 [<c014e680>] arch_get_unmapped_area_topdown+0x0/0x12e [<c014e625>] do_mmap_pgoff+0x1e2/0x23d [<c0181895>] elf_map+0xd8/0x104 [<c0182072>] load_elf_binary+0x5b4/0x11cd [<c015ed73>] search_binary_handler+0x74/0x164 [<c0181abe>] load_elf_binary+0x0/0x11cd [<c015ed7a>] search_binary_handler+0x7b/0x164 [<c015ff2e>] do_execve+0x121/0x16a [<c01012e3>] sys_execve+0x29/0x52 [<c0102c56>] syscall_call+0x7/0xb [<ffffffff>] 0xffffffff -> #0 (&tbl->lock){-+-+}: [<c0132fdf>] __lock_acquire+0x86e/0xafc [<c01332d0>] lock_acquire+0x63/0x80 [<c02691ac>] neigh_lookup+0x43/0xa2 [<c02ebae9>] _read_lock_bh+0x1e/0x2d [<c02691ac>] neigh_lookup+0x43/0xa2 [<c02691ac>] neigh_lookup+0x43/0xa2 [<c02af858>] ndisc_dst_alloc+0xb5/0x155 [<c02b240d>] __ndisc_send+0x72/0x3f5 [<c02a573b>] ip6_output+0x0/0xaad [<c0133225>] __lock_acquire+0xab4/0xafc [<c02b2fb5>] ndisc_send_ns+0x63/0x6e [<c02eb92c>] _read_unlock_bh+0x25/0x28 [<c02b3f3e>] ndisc_solicit+0x183/0x18d [<c0121071>] __mod_timer+0x96/0xa1 [<c026b81e>] neigh_timer_handler+0x214/0x252 [<c0120c90>] run_timer_softirq+0xfe/0x159 [<c026b60a>] neigh_timer_handler+0x0/0x252 [<c011dbfa>] __do_softirq+0x6f/0xe9 [<c011dcae>] do_softirq+0x3a/0x52 [<c011dfc3>] irq_exit+0x44/0x46 [<c0105273>] do_IRQ+0x5a/0x73 [<c0103666>] common_interrupt+0x2e/0x34 [<c02ebd3a>] _spin_unlock_irqrestore+0x38/0x3c [<c02188fb>] tty_ldisc_deref+0x5c/0x63 [<c021a5bd>] tty_write+0x1a8/0x1b9 [<c021c5e1>] write_chan+0x0/0x2a9 [<c021a633>] redirected_tty_write+0x65/0x72 [<c021a5ce>] redirected_tty_write+0x0/0x72 [<c015be18>] vfs_write+0x8c/0x108 [<c015c3a2>] sys_write+0x3b/0x60 [<c0102c56>] syscall_call+0x7/0xb [<ffffffff>] 0xffffffff other info that might help us debug this: 1 lock held by ping6/1058: #0: (&n->lock){-+..}, at: [<c026b620>] neigh_timer_handler+0x16/0x252 stack backtrace: Pid: 1058, comm: ping6 Not tainted 2.6.25-rc1-netns-00113-g69cc64d-dirty #34 [<c013176b>] print_circular_bug_tail+0x5b/0x66 [<c0132fdf>] __lock_acquire+0x86e/0xafc [<c01332d0>] lock_acquire+0x63/0x80 [<c02691ac>] ? neigh_lookup+0x43/0xa2 [<c02ebae9>] _read_lock_bh+0x1e/0x2d [<c02691ac>] ? neigh_lookup+0x43/0xa2 [<c02691ac>] neigh_lookup+0x43/0xa2 [<c02af858>] ndisc_dst_alloc+0xb5/0x155 [<c02b240d>] __ndisc_send+0x72/0x3f5 [<c02a573b>] ? ip6_output+0x0/0xaad [<c0133225>] ? __lock_acquire+0xab4/0xafc [<c02b2fb5>] ndisc_send_ns+0x63/0x6e [<c02eb92c>] ? _read_unlock_bh+0x25/0x28 [<c02b3f3e>] ndisc_solicit+0x183/0x18d [<c0121071>] ? __mod_timer+0x96/0xa1 [<c026b81e>] neigh_timer_handler+0x214/0x252 [<c0120c90>] run_timer_softirq+0xfe/0x159 [<c026b60a>] ? neigh_timer_handler+0x0/0x252 [<c011dbfa>] __do_softirq+0x6f/0xe9 [<c011dcae>] do_softirq+0x3a/0x52 [<c011dfc3>] irq_exit+0x44/0x46 [<c0105273>] do_IRQ+0x5a/0x73 [<c0103666>] common_interrupt+0x2e/0x34 [<c02ebd3a>] ? _spin_unlock_irqrestore+0x38/0x3c [<c02188fb>] tty_ldisc_deref+0x5c/0x63 [<c021a5bd>] tty_write+0x1a8/0x1b9 [<c021c5e1>] ? write_chan+0x0/0x2a9 [<c021a633>] redirected_tty_write+0x65/0x72 [<c021a5ce>] ? redirected_tty_write+0x0/0x72 [<c015be18>] vfs_write+0x8c/0x108 [<c015c3a2>] sys_write+0x3b/0x60 [<c0102c56>] syscall_call+0x7/0xb ======================= On Thu, Feb 14, 2008 at 5:56 PM, Benjamin Thery <[EMAIL PROTECTED]> wrote: > Hi, > > It seems this patch hangs my machine very quickly when there are some > ICMPv6 traffic. > > I'm using net-2.6, pulled today (14th Feb). > > I had some unexpected hangs on my SMP test machines and I bisected the > problem to 69cc64d8d92bf852f933e90c888dfff083bd4fc9 > "[NDISC]: Fix race in generic address resolution". > > Looks like a deadlock: > "BUG: soft lockup - CPU#1 stuck for 61s! [swapper:0]" > > Here are some traces printed on the console: > > Pid: 0, comm: swapper Not tainted (2.6.25-rc1-netns-00113-g69cc64d-dirty #34) > EIP: 0060:[<c02eb5f6>] EFLAGS: 00000287 CPU: 0 > EIP is at __write_lock_failed+0xa/0x20 > EAX: c7b3fab4 EBX: c7b3fab4 ECX: 00000000 EDX: c0377986 > ESI: c7b3fa90 EDI: c7b6f290 EBP: c03cbd24 ESP: c03cbd24 > DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 > CR0: 8005003b CR2: b7f9b404 CR3: 07ac8000 CR4: 00000690 > DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > DR6: 00000000 DR7: 00000000 > [<c020e43f>] _raw_write_lock+0x57/0x6c > [<c02eba95>] _write_lock_bh+0x25/0x2d > [<c026b107>] ? neigh_resolve_output+0x93/0x238 > [<c026b107>] neigh_resolve_output+0x93/0x238 > [<c02a5635>] ip6_output2+0x241/0x289 > [<c02a61cd>] ip6_output+0xa92/0xaad > [<c025ff11>] ? __alloc_skb+0x4f/0xfb > [<c02b2596>] ? __ndisc_send+0x1fb/0x3f5 > [<c02b26a0>] __ndisc_send+0x305/0x3f5 > [<c02b2fb5>] ndisc_send_ns+0x63/0x6e > [<c02b3f3e>] ndisc_solicit+0x183/0x18d > [<c0121071>] ? __mod_timer+0x96/0xa1 > [<c026b81e>] neigh_timer_handler+0x214/0x252 > [<c0120c90>] run_timer_softirq+0xfe/0x159 > [<c026b60a>] ? neigh_timer_handler+0x0/0x252 > [<c011dbfa>] __do_softirq+0x6f/0xe9 > [<c011dcae>] do_softirq+0x3a/0x52 > [<c011dfc3>] irq_exit+0x44/0x46 > [<c0105273>] do_IRQ+0x5a/0x73 > [<c0103666>] common_interrupt+0x2e/0x34 > [<c0101954>] ? default_idle+0x4a/0x77 > [<c010190a>] ? default_idle+0x0/0x77 > [<c0101855>] cpu_idle+0x89/0x9d > [<c02e6135>] rest_init+0x49/0x4b > ======================= > BUG: soft lockup - CPU#1 stuck for 61s! [swapper:0] > > Pid: 0, comm: swapper Not tainted (2.6.25-rc1-netns-00113-g69cc64d-dirty #34) > EIP: 0060:[<c02eb5f6>] EFLAGS: 00000287 CPU: 1 > EIP is at __write_lock_failed+0xa/0x20 > EAX: c7b3fab4 EBX: c7b3fab4 ECX: 00000000 EDX: 00000000 > ESI: c03bb9c0 EDI: c7b3fab4 EBP: c7841eb0 ESP: c7841eb0 > DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 > CR0: 8005003b CR2: 08560008 CR3: 07b04000 CR4: 00000690 > DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > DR6: 00000000 DR7: 00000000 > [<c020e43f>] _raw_write_lock+0x57/0x6c > [<c02eba68>] _write_lock+0x20/0x28 > [<c026982c>] ? neigh_periodic_timer+0x99/0x142 > [<c026982c>] neigh_periodic_timer+0x99/0x142 > [<c0120c90>] run_timer_softirq+0xfe/0x159 > [<c0269793>] ? neigh_periodic_timer+0x0/0x142 > [<c011dbfa>] __do_softirq+0x6f/0xe9 > [<c011dcae>] do_softirq+0x3a/0x52 > [<c011dfc3>] irq_exit+0x44/0x46 > [<c010d680>] smp_apic_timer_interrupt+0x71/0x81 > [<c0103747>] apic_timer_interrupt+0x33/0x38 > [<c0101954>] ? default_idle+0x4a/0x77 > [<c010190a>] ? default_idle+0x0/0x77 > [<c0101855>] cpu_idle+0x89/0x9d > ======================= > BUG: soft lockup - CPU#0 stuck for 61s! [swapper:0] > > Pid: 0, comm: swapper Not tainted (2.6.25-rc1-netns-00113-g69cc64d-dirty #34) > EIP: 0060:[<c02eb5f6>] EFLAGS: 00000287 CPU: 0 > EIP is at __write_lock_failed+0xa/0x20 > EAX: c7b3fab4 EBX: c7b3fab4 ECX: 00000000 EDX: c0377986 > ESI: c7b3fa90 EDI: c7b6f290 EBP: c03cbd24 ESP: c03cbd24 > DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 > CR0: 8005003b CR2: b7f9b404 CR3: 07ac8000 CR4: 00000690 > DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > DR6: 00000000 DR7: 00000000 > [<c020e43f>] _raw_write_lock+0x57/0x6c > [<c02eba95>] _write_lock_bh+0x25/0x2d > [<c026b107>] ? neigh_resolve_output+0x93/0x238 > [<c026b107>] neigh_resolve_output+0x93/0x238 > [<c02a5635>] ip6_output2+0x241/0x289 > [<c02a61cd>] ip6_output+0xa92/0xaad > [<c025ff11>] ? __alloc_skb+0x4f/0xfb > [<c02b2596>] ? __ndisc_send+0x1fb/0x3f5 > [<c02b26a0>] __ndisc_send+0x305/0x3f5 > [<c02b2fb5>] ndisc_send_ns+0x63/0x6e > [<c02b3f3e>] ndisc_solicit+0x183/0x18d > [<c0121071>] ? __mod_timer+0x96/0xa1 > [<c026b81e>] neigh_timer_handler+0x214/0x252 > [<c0120c90>] run_timer_softirq+0xfe/0x159 > [<c026b60a>] ? neigh_timer_handler+0x0/0x252 > [<c011dbfa>] __do_softirq+0x6f/0xe9 > [<c011dcae>] do_softirq+0x3a/0x52 > [<c011dfc3>] irq_exit+0x44/0x46 > [<c0105273>] do_IRQ+0x5a/0x73 > [<c0103666>] common_interrupt+0x2e/0x34 > [<c0101954>] ? default_idle+0x4a/0x77 > [<c010190a>] ? default_idle+0x0/0x77 > [<c0101855>] cpu_idle+0x89/0x9d > [<c02e6135>] rest_init+0x49/0x4b > ======================= > BUG: soft lockup - CPU#1 stuck for 61s! [swapper:0] > ... > > > Benjamin > > > > On Tue, Feb 12, 2008 at 6:47 AM, David Miller <[EMAIL PROTECTED]> wrote: > > From: Frank Blaschka <[EMAIL PROTECTED]> > > Date: Mon, 11 Feb 2008 10:01:20 +0100 > > > > > > > we run your patch during the weekend on single CPU and SMP > > > machines. We do not see any problems. Thanks for providing the fix. > > > > Thanks for testing Frank, I can now push this fix upstream. > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe netdev" in > > the body of a message to [EMAIL PROTECTED] > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html