2.6.0-test7: Preempt enabled -> kernel panic

2.6.0-test7: Preempt enabled -> kernel panic

[Markus Schoder]

When compiling 2.6.0-test7 with preempt I get a kernel panic
when running the tst-eintr1 test program from the nptl 0.60 package.
It does not happen every time but running it repeatedly will lead
to a panic pretty quickly.

With preempt disabled it's rock solid.

Stack trace is not always the same but there always seems to
be infinite recursion. Also sometimes interrupts are disabled
(no SysRq) and sometimes not.

This is on an Athlon XP, kernel compiled with gcc 3.3.1.

Example stack trace:

...
do_page_fault+0x12c/0x454
poke_blanked_console+0x5c/0x70
try_to_wake_up+0xa7/0x160
default_wake_function+0x2a/0x30
__wake_up_common+0x31/0x60
do_page_fault+0x0/0x454
error_code+0x2d/0x38
do_exit+0x1d2/0x350
do_page_fault+0x0/0x454
die+0xe1/0xf0
do_page_fault+0x12c/0x454
sys_exit+0x13/0x20
syscall_call+0x7/0xb

Code: 8b 5d 68 c7 44 24 20 01 00 03 00 8b 50 14 8b 00 81 e2 ff ff
<6>note: ld-linux.so.2[2069] exited with preempt_count 1

--
Markus

Re: 2.6.0-test7: Preempt enabled -> kernel panic

[bill davidsen]

In article <200310172319.59776.markus_schoder@yahoo.de>,
Markus Schoder  <markus_schoder@yahoo.de> wrote:
| When compiling 2.6.0-test7 with preempt I get a kernel panic
| when running the tst-eintr1 test program from the nptl 0.60 package.
| It does not happen every time but running it repeatedly will lead
| to a panic pretty quickly.
| 
| With preempt disabled it's rock solid.
| 
| Stack trace is not always the same but there always seems to
| be infinite recursion. Also sometimes interrupts are disabled
| (no SysRq) and sometimes not.

I usually run 2.6 kernels with both softdog and NMI watchdog, have no
idea if that would help other than to possibly force a reboot.
 
| This is on an Athlon XP, kernel compiled with gcc 3.3.1.

Check the list, there was something about gcc version, don't remember
exactly what.
-- 
bill davidsen <davidsen@tmr.com>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.