On Fri, 9 Aug 2024, Michael Schmitz wrote:
I tried out the "stress-ng --sysbadaddr -1" test, and that didn't go
so well for me:
# stress-ng --sysbadaddr -1
stress-ng: info: [37] defaulting to a 86400 second (1 day, 0.00 secs) run
per stressor
stress-ng: info: [37] dispatching hogs: 1 sysbadaddr
*** ILLEGAL INSTRUCTION *** FORMAT=4
Current process id is 39
BAD KERNEL TRAP: 00000000
Modules linked in:
PC: [<00000000>] 0x0
SR: 2004 SP: 6504e563 a2: 008ee380
d0: 000000f7 d1: 00000000 d2: 00000000 d3: 00000000
d4: 00a87b80 d5: bfbf3814 a0: 00000000 a1: bfbf3814
Process stress-ng-sysba (pid: 39, task=4dbb2ec5)
Frame format=4 eff addr=480a2004 pc=0002b154
Stack from 00adff20:
00ade000 00000000 00000000 000000f7 00000000 00000004 00a87b80
00000000
00000000 00000000 00000000 008ee380 0002ab5c 00000100 00000122
fffffff6
bfbf376c 0002b29e 000000f7 bfbf3814 00000000 00000000 00ade000
0002b222
00ae0800 80118988 00000000 00000005 bfbf37a0 00000005 bfbf3814
00adffcc
00023d2c 00adffcc 00000000 00000000 00000000 00000000 000000f7
00000000
80118b46 00021850 00024b00 000000f7 bfbf3814 00000000 00000000
bfbf3814
Call Trace: [<0002ab5c>] child_wait_callback+0x0/0x24
[<0002b29e>] sys_wait4+0x7c/0x8e
[<0002b222>] sys_wait4+0x0/0x8e
[<00023d2c>] buserr_c+0xb0/0x152
[<00021850>] buserr+0x28/0x30
[<00024b00>] system_call+0x54/0xa8
But that is the same with and without these patches.
I wonder if recent signal handling changes (e.g. commit
0d4276cfbe6fd4c4a21acdee803b05a3a6192082) have rare unexpected side effects on
Coldfire here ... OTOH, signal handling as such works just fine, right?
That would be commit b845b574f86d ("m68k: Move signal frame following
exception on 68020/030") on mainline. If it caused a regression, that
would have first appeared in v6.4. I can't imagine how that commit could
affect Coldfire but that's no reason not to test an older kernel.
FWIW, my hunch is that the other stressors which call wait4() will
probably crash too (regardless of kernel version).
