[mainline] powerpc/TM: Unexpected TM Bad Thing during core dump on POWER9 (7.1‑rc1)

[Venkat Rao Bagalkote <venkat88@linux.ibm.com>]

Greetings!!

IBM CI has reported a kernel crash while running 
selftests/powerpc/signal on a POWER9 pSeries system.

I attempted to reproduce this issue manually, but was not successful so far.

Below are the details of the crash as reported by CI.

Crash Details:

[ 9798.880148] Unexpected TM Bad Thing exception at c00000000000dbac
                (msr 0x8000000302a03031) tm_scratch=800000010280b033
[ 9798.880160] Oops: Unrecoverable exception, sig: 6 [#1]
[ 9798.880165] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=8192 NUMA pSeries
[ 9798.880173] Modules linked in: nvram(E) rpadlpar_io(E) rpaphp(E) ...
[ 9798.880233] CPU: 8 UID: 0 PID: 1039530 Comm: sigfuz
                Tainted: G            E       7.1.0-rc1 #1 PREEMPT
[ 9798.880245] Hardware name: IBM,8375-42A POWER9 (architected)
                hv:phyp pSeries
[ 9798.880251] NIP:  c00000000000dbac LR: 0000000010001e58
[ 9798.880262] MSR:  8000000302a03031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[SE]>


Call Trace:


NIP [c00000000000dbac] interrupt_return_srr_kernel+0x15c/0x18c
Call Trace:
  tm_reclaim_thread
  flush_tmregs_to_thread
  vsr_get
  regset_get_alloc
  fill_thread_core_info.isra.0
  fill_note_info
  elf_core_dump
  coredump_write
  do_coredump
  vfs_coredump
  get_signal
  do_signal
  do_notify_resume
  interrupt_exit_user_prepare_main
  interrupt_exit_user_prepare
  interrupt_return_srr_user


Please let me know if further details are required.


If you happen to fix this issue, please add below tag.

Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>



Regards,

Venkat.