Gregory Haskins wrote: > Gregory Haskins wrote: > >> Hi Chirag >> >> Chirag Jog wrote: >> >> >>> Hi Gregory, >>> We see the following BUG followed by a hang on the latest kernel 2.6.26.5-rt9 on a Power6 blade (PPC64) >>> It is easily recreated by running the async_handler or sbrk_mutex (realtime tests from ltp) tests. >>> >>> >>> >> Call me an LTP newbie, but where can I get the sbrk_mutex/async_handler >> tests. >> > Ok, I figured out this part. I needed a newer version of the .rpm from > a different repo. However, both async_handler and sbrk_mutex seem to > segfault for me. Hmm > Thanks to help from Darren I got around this issue. Unfortunately both tests pass so I cannot reproduce this issue, nor do I see the problem via code inspection. Ill keep digging but I am currently at a loss. I may need to send you some diagnostic patches to find this, if that is ok with you Chirag? -Greg > --- > > ghaskins@test:~> uname -a > Linux test 2.6.26.5-rt9-rt #1 SMP PREEMPT RT Mon Sep 29 14:26:45 EDT > 2008 x86_64 x86_64 x86_64 GNU/Linux > > test:/home/ghaskins # > /usr/lib64/ltp/testcases/realtime/func/async_handler/async_handler > > ----------------------------------- > Asynchronous Event Handling Latency > ----------------------------------- > > jvmsim disabled > Running 1000000 iterations > Segmentation fault > > --- > > Any ideas? > > -Greg > > >> I installed the LTP rpm and I dont seem to have tests by that >> name. I have a 26.5-rt9 kernel all configured and ready to go but no >> way to reproduce this issue. Please advise. >> >> Regards, >> -Greg >> >> >> >> >>> login: cpu 0x2: Vector: 700 (Program Check) at [c0000000e8e875d0] >>> pc: c00000000005110c: .pick_next_pushable_task+0x54/0x9c >>> lr: c000000000059f50: .push_rt_task+0x44/0x2b4 >>> sp: c0000000e8e87850 >>> msr: 8000000000021032 >>> current = 0xc0000000ea5bb2e0 >>> paca = 0xc000000000608700 >>> pid = 2811, comm = async_handler >>> kernel BUG at kernel/sched_rt.c:1041! <--------------------- >>> enter ? for help >>> [link register ] c000000000059f50 .push_rt_task+0x44/0x2b4 >>> [c0000000e8e87850] c0000000e8e878f0 (unreliable) >>> [c0000000e8e87900] c00000000005a1dc .push_rt_tasks+0x1c/0x38 >>> [c0000000e8e87980] c00000000005a21c .post_schedule_rt+0x24/0x44 >>> [c0000000e8e87a10] c000000000057cbc .finish_task_switch+0xd0/0x180 >>> [c0000000e8e87ab0] c0000000003b6e88 .__schedule+0x6e0/0x798 >>> [c0000000e8e87b90] c0000000003b7148 .schedule+0xec/0x11c >>> [c0000000e8e87c10] c0000000003b7a40 .do_nanosleep+0x6c/0xcc >>> [c0000000e8e87c90] c000000000080738 .hrtimer_nanosleep+0x7c/0x100 >>> [c0000000e8e87d90] c000000000080830 .sys_nanosleep+0x74/0x94 >>> [c0000000e8e87e30] c0000000000086ac syscall_exit+0x0/0x40 >>> --- Exception: c00 (System Call) at 0000008026449844 >>> SP (400014185f0) is in userspace >>> >>> >>> This is generated by the BUG_ON lines in the pick_next_pushable function >>> introduced by the sched-only-push-once-per-queue.patch . >>> >>> The -rt kernel prior to this patch didnot give such BUGes. >>> >>> All this was tried with >>> CONFIG_GROUP_SCHED=N >>> CONFIG_RT_GROUP_SCHED=N >>> >>> >>> Setting the options >>> CONFIG_GROUP_SCHED=y >>> CONFIG_RT_GROUP_SCHED=Y, >>> seems to solve the problem. >>> >>> >>> >>> >>> >>> >> >> > > >
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