Hello Gaurav. On 2018-01-09, Kohli, Gaurav <gkohli@xxxxxxxxxxxxxx> wrote: > We are seeing crash in do_task_stat while accessing stack pointer, It > seems same task has already completed do_exit call. > So it seems a race between them: > > Below is the crash trace: > 49750.534377] Kernel BUG at ffffff8e7a4c53a8 [verbose debug info > unavailable] > [49750.534394] task: ffffffe7b4475580 task.stack: ffffffe7a5f0c000 > [49750.534400] PC is at do_task_stat+0x740/0x908 > [49750.534402] LR is at do_task_stat+0xa4/0x908 > [49750.534403] pc : [<ffffff8e7a4c53a8>] lr : [<ffffff8e7a4c4d0c>] > pstate: 80400145 > [49750.534404] sp : ffffffe7a5f0fbd0 > > and here is stack trace on that core: > > -000|user_stack_pointer(inline) > -000|do_task_stat( > | m = 0xFFFFFFE7A5CD7380, > | ns = 0xFFFFFF8E7C43C748, > | ?, > | task = 0xFFFFFFE80D8C2280, > | ?) > | tty_pgrp = 0 > | ppid = 2084696064 > | sid = 0 > | mm = 0xFFFFFFE7B4424140 > | tcomm = (84, 9, 71, 122, 142, 255, 255, 255, 48, 253, 240, 165, > 231, 255, 255, 255) > | flags = 18446743969119403392 > -001|proc_tgid_stat( > | m = 0xFFFFFFE7A5CD7380, > | ?, > > Below are task stats which shows , process completed the do_exit call: > struct task_struct.flags -x 0xFFFFFFE80D8C2280 > flags = 0x40870c > > crash_64> struct task_struct.exit_code -x 0xFFFFFFE80D8C2280 > exit_code = 0x6 > > struct task_struct.state -x 0xFFFFFFE80D8C2280 > state = 0x40 I am confused why this task is in the TASK_PARKED state. What kind of task is this? > In our build both patches are there , > fs/proc: report eip/esp in /prod/PID/stat for coredumping > > and also task.state has already set PF_DUMPCORE as it got the sigabrt > signal. John Ogness -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
