linux-2.6.21-CITI_NFS4_ALL-1.diff BUG: soft lockup detected

[Le Rouzic]

Hi,

Using Intel x86_64 SMP as client and server and running the patch
linux-2.6.21-CITI_NFS4_ALL-1.diff on both client and server
the client machine  hanged when running the dbench benchmark with 1000 users
under a krb5 mount.

I got the following in /var/log/messages:

kernel: Process kswapd0 (pid: 252, threadinfo ffff810037f0a000, task 
ffff810037e72790)
kernel: Stack:  ffff8100209e95e8 ffffffff8030b4f3 ffff8100724e1a58 
ffff8100724e1a58
kernel:  ffff810002c26c40 00000000000011f8 0000000000000080 00000000000000d0
kernel:  0000000000000000 ffffffff8025f0d0 0000000000072553 0000000000000080
kernel: Call Trace:
kernel:  [<ffffffff8030b4f3>] nfs_access_cache_shrinker+0x124/0x1c3
kernel:  [<ffffffff8025f0d0>] shrink_slab+0xdc/0x154
kernel:  [<ffffffff8025fa18>] kswapd+0x330/0x465
kernel:  [<ffffffff8023a948>] autoremove_wake_function+0x0/0x2e
kernel:  [<ffffffff8025f6e8>] kswapd+0x0/0x465
kernel:  [<ffffffff8023a5b2>] keventd_create_kthread+0x0/0x6a
kernel:  [<ffffffff8023a819>] kthread+0xd1/0x100
kernel:  [<ffffffff8020a938>] child_rip+0xa/0x12
kernel:  [<ffffffff8023a5b2>] keventd_create_kthread+0x0/0x6a
kernel:  [<ffffffff8023a748>] kthread+0x0/0x100
kernel:  [<ffffffff8020a92e>] child_rip+0x0/0x12
kernel:
kernel:
kernel: Code: 48 8b 40 28 48 85 c0 74 02 ff d0 48 8d 7b 48 48 c7 c6 a0 1a
kernel: RIP  [<ffffffff8028cc4e>] iput+0x27/0x7b
kernel:  RSP <ffff810037f0bda0>
kernel: BUG: soft lockup detected on CPU#0!
kernel:
kernel: Call Trace:
kernel:  <IRQ>  [<ffffffff80253069>] softlockup_tick+0xdb/0xf6
kernel:  [<ffffffff8022d180>] __do_softirq+0x55/0xc3
kernel:  [<ffffffff80230cff>] update_process_times+0x42/0x68
kernel:  [<ffffffff802167b6>] smp_local_timer_interrupt+0x34/0x55
kernel:  [<ffffffff80216ebd>] smp_apic_timer_interrupt+0x43/0x5a
kernel:  [<ffffffff8020a756>] apic_timer_interrupt+0x66/0x70
kernel:  <EOI>  [<ffffffff805b5caf>] gss_unwrap_resp+0x0/0x1e1
kernel:  [<ffffffff80408931>] __delay+0x4/0x10
kernel:  [<ffffffff8040a392>] _raw_spin_lock+0x8e/0xf6
kernel:  [<ffffffff8030b000>] nfs_access_add_cache+0x16d/0x1b9
kernel:  [<ffffffff8030b34b>] nfs_permission+0x14d/0x1d1
kernel:  [<ffffffff802821eb>] permission+0xaf/0xf7
kernel:  [<ffffffff80283310>] may_open+0x5b/0x21b
kernel:  [<ffffffff802857f8>] open_namei+0x2d1/0x659
kernel:  [<ffffffff80279e1e>] do_filp_open+0x1c/0x38
kernel:  [<ffffffff8028507b>] sys_mkdirat+0xc5/0xd8
kernel:  [<ffffffff80279bbd>] get_unused_fd+0xf9/0x107
kernel:  [<ffffffff80279e7e>] do_sys_open+0x44/0xc1
kernel:  [<ffffffff80209b1e>] system_call+0x7e/0x83
kernel:
kernel: BUG: soft lockup detected on CPU#0!
kernel:
kernel: Call Trace:
kernel:  <IRQ>  [<ffffffff80253069>] softlockup_tick+0xdb/0xf6
kernel:  [<ffffffff8022d180>] __do_softirq+0x55/0xc3
kernel:  [<ffffffff80230cff>] update_process_times+0x42/0x68
kernel:  [<ffffffff802167b6>] smp_local_timer_interrupt+0x34/0x55
kernel:  [<ffffffff80216ebd>] smp_apic_timer_interrupt+0x43/0x5a
kernel:  [<ffffffff8020a756>] apic_timer_interrupt+0x66/0x70
kernel:  <EOI>  [<ffffffff805b5caf>] gss_unwrap_resp+0x0/0x1e1
kernel:  [<ffffffff80408935>] __delay+0x8/0x10
kernel:  [<ffffffff8040a392>] _raw_spin_lock+0x8e/0xf6
kernel:  [<ffffffff8030b000>] nfs_access_add_cache+0x16d/0x1b9
kernel:  [<ffffffff8030b34b>] nfs_permission+0x14d/0x1d1
kernel:  [<ffffffff802821eb>] permission+0xaf/0xf7
kernel:  [<ffffffff80283310>] may_open+0x5b/0x21b
kernel:  [<ffffffff802857f8>] open_namei+0x2d1/0x659
kernel:  [<ffffffff80279e1e>] do_filp_open+0x1c/0x38
kernel:  [<ffffffff8028507b>] sys_mkdirat+0xc5/0xd8
kernel:  [<ffffffff80279bbd>] get_unused_fd+0xf9/0x107
kernel:  [<ffffffff80279e7e>] do_sys_open+0x44/0xc1
kernel:  [<ffffffff80209b1e>] system_call+0x7e/0x83
kernel:
kernel: BUG: soft lockup detected on CPU#0!

You can get more at:
http://developer.osdl.org/dev/nfsv4/bugzilla/show_bug.cgi?id=141

Best regards

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