Re: kernel BUG at kernel/exit.c:792!

[Manfred Spraul <manfred@colorfullife.com>]

Srivatsa Vaddagiri wrote:

> --- base.c 2003-10-26 00:13:57.000000000 +0530
>
>>+++ base.c.fix	2003-12-03 17:20:18.877679360 +0530
>>@@ -1669,7 +1669,7 @@
>> 	do {
>> 		int tid = task->pid;
>> 		if (!pid_alive(task))
>>-			continue;
>>+			break;
>>
No, a break would be wrong: The test detects already dead tasks that are 
still listed in the task list. If such a task is found, then it 
shouldn't be listed in /proc/, but the readdir call should continue to 
scan the task list.

But I don't understand the oops:
__exit_sighand clears current->sighand, and then in the next line 
__unhash_process removes the thread from the task list. But that's under 
write_lock_irq(&tasklist_lock), and get_tid_list runs under 
read_lock(&tasklist_lock). It should be impossible that ->sighand is 
NULL and the task is still listed in the task list.

--
    Manfred