Hi, I could reproduce the bug on intel x86_64 with LTP's sbrk_mutex: kernel BUG at kernel/sched_rt.c:1044! invalid opcode: 0000 [1] PREEMPT SMP CPU 5 Modules linked in: mptsas scsi_transport_sas Pid: 27577, comm: sbrk_mutex Not tainted 2.6.26.5-rt9-00002-g3b27927 #23 RIP: 0010:[<ffffffff80227f95>] [<ffffffff80227f95>] pick_next_pushable_task+0x6 1/0x77 RSP: 0018:ffff81007713fd28 EFLAGS: 00010046 RAX: 0000000000000005 RBX: ffff810083a4e280 RCX: ffff81013dcee458 RDX: ffff8100771f8000 RSI: ffff81013dcee2c0 RDI: ffff810083a4e280 RBP: ffff81007713fd28 R08: ffff81007713e000 R09: 0000000000000000 R10: 000000004bbbc9e0 R11: ffff81007dc3bde8 R12: ffff81023ff7c910 R13: ffff8101bf4ad0c0 R14: 0000000000000001 R15: ffff810083a4e280 FS: 000000004d3bf940(0063) GS:ffff81013f4458c0(0000) knlGS:00000000f7f216c0 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 000000389d495770 CR3: 000000007c11a000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process sbrk_mutex (pid: 27577, threadinfo ffff81007713e000, task ffff8100771d61 c0) Stack: ffff81007713fd68 ffffffff8022b1ce ffff81007713fdc8 ffff810083a4e280 ffff81023ff7c910 ffff8101bf4ad0c0 0000000000000001 0000000000000000 ffff81007713fd88 ffffffff8022b3c3 ffff81007713fda8 ffff810083a4e280 Call Trace: [<ffffffff8022b1ce>] push_rt_task+0x26/0x207 [<ffffffff8022b3c3>] push_rt_tasks+0x14/0x1c [<ffffffff8022b3e4>] post_schedule_rt+0x19/0x25 [<ffffffff8022d7e9>] finish_task_switch+0x73/0x121 [<ffffffff805bbe3d>] thread_return+0x4f/0xdc [<ffffffff805bc066>] schedule+0xd4/0xf0 [<ffffffff805bc686>] do_nanosleep+0x5c/0x9c [<ffffffff80248350>] ? hrtimer_nanosleep+0x54/0xbd [<ffffffff80247c9d>] ? hrtimer_wakeup+0x0/0x21 [<ffffffff805bc66b>] ? do_nanosleep+0x41/0x9c [<ffffffff8022e9f4>] ? schedule_tail+0x43/0x97 [<ffffffff80248405>] ? sys_nanosleep+0x4c/0x62 [<ffffffff8020b32a>] ? system_call_after_swapgs+0x8a/0x8f Code: 42 18 74 04 0f 0b eb fe 48 39 b7 48 0e 00 00 75 04 0f 0b eb fe 83 b9 50 ff ff ff 01 7f 04 0f 0b eb fe 83 b9 e0 fe ff ff 00 75 04 <0f> 0b eb fe 83 b9 8c fe ff ff 63 7e 04 0f 0b eb fe c9 48 89 f0 RIP [<ffffffff80227f95>] pick_next_pushable_task+0x61/0x77 RSP <ffff81007713fd28> The difference with powerpc64 is that you need to be patient: it takes tens of minutes to BUG/hang on intel whereas on power it's almost immediate. I just posted the patch on this list (Fix pushable_task list corruption) Greg, please can you review this patch and comment? Thanks. Gilles. -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
