Re: yet another kernel panic

[Rum <rumko@xxxxxxxxxxxxxxxxxxxxxxxxx>]

On 2004-08-29, Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx> wrote:
>
>:i have a build of 1.1-current from around 19th of august (old, but maybe the
>:bug is still present today) and experienced a kernel panic, was running
>:xorg with kde (kdebase, kdelibs, kdegames and thats about it), firefox,
>:konsole, xmms, xterm and perhaps another app or two. the kernel panic
>:happened when i tried running top (weird) ... the dump is located at:
>:leaf:~rumko/memory_dumps/dump-28.8.04-16-46.tar.bz2
>:i also have a backtrace if its usefull:
>:
>:...
>:#6  0xc01c97b8 in fill_eproc (p=0xceff8200, ep=0xcf70f81c) at
>:/usr/src/sys/kern/kern_proc.c:411
>:#7  0xc01c990d in sysctl_out_proc (p=0xceff8200, td=0xc9a5db80,
>:req=0xcf70fb50, doingzomb=0)
>:    at /usr/src/sys/kern/kern_proc.c:461
>:#8  0xc01c9baa in sysctl_kern_proc (oidp=0xc03fe3c0, arg1=0x0, arg2=0,
>
>     Ok, here's a patch to try.  fill_eproc() checks for p_stats == NULL
>     but it looks like I don't NULL it out when I deallocate the process's
>     kernel stack (which is where the stats are located).  If a process is
>     left a zombie long enough the kernel's kstack cache might cause the
>     stack to be deallocated, leading to a panic in the eproc code.
>
> 						-Matt
>
> Index: vm_glue.c
>===================================================================
> RCS file: /cvs/src/sys/vm/vm_glue.c,v
> retrieving revision 1.27
> diff -u -r1.27 vm_glue.c
> --- vm_glue.c	15 Aug 2004 15:00:22 -0000	1.27
> +++ vm_glue.c	29 Aug 2004 16:45:15 -0000
> @@ -275,6 +275,7 @@
>  void
>  vm_waitproc(struct proc *p)
>  {
> +	p->p_stats = NULL;
>  	cpu_proc_wait(p);
>  	vmspace_exitfree(p);	/* and clean-out the vmspace */
>  }

i tried updating the source and checked just in case is the line i had to add
manually is still there ... and its not ... shouldnt this be commited in the
cvs or does that panic only occur on my machine?