Dear All, We've just tried v3.0.34-rt55 on a PowerPC and we've got the same results that we had on the i686 nearly a year ago. The OOPS is as follows: ------------[ cut here ]------------ kernel BUG at kernel/rtmutex.c:725! Oops: Exception in kernel mode, sig: 5 [#1] PREEMPT SMP NR_CPUS=8 CPC-3801 Modules linked in: cpc(-) [last unloaded: cpc] NIP: c04e5058 LR: c04e503c CTR: 00000000 REGS: e8043c00 TRAP: 0700 Not tainted (3.0.34-rt55) MSR: 00029002 <EE,ME,CE> CR: 82000842 XER: 20000000 TASK = e80207f0[906] 'rmmod' THREAD: e8042000 CPU: 3 GPR00: 00000001 e8043cb0 e80207f0 00000000 e80207f0 00000000 00000001 00000000 GPR08: e80207f0 e80207f0 e80207f0 e80207f1 00000001 1001a534 bff65560 00000000 GPR16: 00000004 00000000 00000020 00000000 00000004 00000000 00000020 00000000 GPR24: c065d234 e9b02628 00100100 c065b348 e9f8cf20 c062dc24 e80207f0 c0cfdc24 NIP [c04e5058] rt_spin_lock_slowlock+0x80/0x278 LR [c04e503c] rt_spin_lock_slowlock+0x64/0x278 Call Trace: [e8043cb0] [c04e503c] rt_spin_lock_slowlock+0x64/0x278 (unreliable) [e8043d20] [c00daa58] kmem_cache_free+0x74/0x11c [e8043d40] [c00dad3c] free_block+0x1a4/0x1b0 [e8043d70] [c00dafac] do_drain+0x94/0x124 [e8043db0] [c00d9ef8] slab_on_each_cpu+0x48/0x90 [e8043dd0] [c00db3b4] __cache_shrink+0x28/0xc8 [e8043de0] [c00db664] kmem_cache_destroy+0x74/0x118 [e8043df0] [f3041894] cpc_command_buffer_term+0x40/0xd4 [cpc] [e8043e00] [f3042f34] cpc_command_buffer_queue_term+0x38/0x68 [cpc] [e8043e10] [f304973c] cpc_remove+0x38/0x1bc [cpc] [e8043e30] [c028b7e4] pci_device_remove+0x38/0x74 [e8043e40] [c02c8a88] __device_release_driver+0x6c/0xd0 [e8043e50] [c02c8bd0] driver_detach+0xe4/0xe8 [e8043e70] [c02c7950] bus_remove_driver+0x9c/0x114 [e8043e90] [c02c94f4] driver_unregister+0x60/0x8c [e8043ea0] [c028bb0c] pci_unregister_driver+0x58/0xf0 [e8043ec0] [f30496f4] cpc_exit+0x18/0x28 [cpc] [e8043ed0] [c00832f4] sys_delete_module+0x198/0x238 [e8043f40] [c000f10c] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xfe9aa2c LR = 0x1000198c Instruction dump: 7fe3fb78 7fc4f378 38a00000 38c00001 4bb9725d 2f830000 409e0174 801f0010 5400003c 7fc00278 7c000034 5400d97e <0f000000> 3bbe0500 3b810008 7fa3eb78 ---[ end trace 0000000000000002 ]--- note: rmmod[906] exited with preempt_count 1 Does anyone have any ideas what this might be? The problem only occurs when calling kmem_cache_destroy after a large volume of objects have passed through it. Cheers, Chris -----Original Message----- From: Peter Zijlstra [mailto:peterz@xxxxxxxxxxxxx] Sent: 06 September 2011 12:59 To: PRINGLE Chris Cc: linux-rt-users@xxxxxxxxxxxxxxx Subject: Re: kmem_cache_destroy issue with RT12 patch on v3.0.3 (perhaps related to thread 3.0.4 + rt12: deadlock?) On Fri, 2011-09-02 at 12:02 +0100, PRINGLE Chris wrote: > The following code causes the a kernel OOPS at the point where I call > kmem_cache_destroy: > What does that oops look like? ��.n��������+%������w��{.n�����{�����ǫ���ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
