diff options
| author | Haren Myneni <haren@us.ibm.com> | 2005-08-03 15:08:18 +1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-08-02 22:16:45 -0700 |
| commit | 5cb4cc0d8211c490537c8568001958fc76741312 (patch) | |
| tree | 3a3844a79cff56d84ecafd65ba5d8da25e158d2b | |
| parent | 0b2bfb4e7ff61f286676867c3508569bea6fbf7a (diff) | |
| download | op-kernel-dev-5cb4cc0d8211c490537c8568001958fc76741312.zip op-kernel-dev-5cb4cc0d8211c490537c8568001958fc76741312.tar.gz | |
[PATCH] Xmon bug fix for soft-reset
For soft reset during system hang, got an error "CPU did not take
control" for some CPUs even though they responded to soft-reset (called
SystemReset, die and called debugger - xmon). First these CPUs entered
into xmon by IPI callback and then got a soft-reset exception and
re-entered into xmon again. The first CPU which re-entered into xmon got
the output lock and made into xmon successfully without unlocking.
Hence, the next CPU(s) which re-entered into xmon try to acquire a lock
(get_output_lock). Therefore, we can not view state of those CPU(s).
[This is a simple, very low risk, obvious fix for an obvious bug, and
should go into 2.6.13. -- paulus]
Signed-off-by: Haren Myneni <hbabu@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | arch/ppc64/xmon/xmon.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/ppc64/xmon/xmon.c b/arch/ppc64/xmon/xmon.c index 7f6e13a..0553943 100644 --- a/arch/ppc64/xmon/xmon.c +++ b/arch/ppc64/xmon/xmon.c @@ -329,13 +329,16 @@ int xmon_core(struct pt_regs *regs, int fromipi) printf("cpu 0x%x: Exception %lx %s in xmon, " "returning to main loop\n", cpu, regs->trap, getvecname(TRAP(regs))); + release_output_lock(); longjmp(xmon_fault_jmp[cpu], 1); } if (setjmp(recurse_jmp) != 0) { if (!in_xmon || !xmon_gate) { + get_output_lock(); printf("xmon: WARNING: bad recursive fault " "on cpu 0x%x\n", cpu); + release_output_lock(); goto waiting; } secondary = !(xmon_taken && cpu == xmon_owner); |
