Ralf Baechle wrote:
On Wed, Aug 06, 2003 at 07:00:07PM +0800, Fuxin Zhang wrote:I think so. Just in case the hardware is doing something strange:)
And here I have a question for Mr. Adam: original linux code use 'Writeback_Inv_D"
and "Hit_Invalidate_I",not "Writeback_D" and "Hit_Invalidate_I",could it lead to the
problem?
No. To synchronize the D-cache and I-cache it's irrelevant if you
invalidate the D-cache or not.
Thanks:)
BTW:
a silly question: how can i make my email show up pretier? I find that the mailing list
often break my lines very badly. I feel guilty for that:) I am using mozilla composer,the
original linebreaks are manually inserted(hit enter when i feel it is long enough).
Format your email with hard breaks to about 75 columns. 75 columns because god made vt100 with 80 columns so that leaves a bit of space for quoting your mail nicely.
I am not sure. It is stardard X distribution from debian-woody. Fairly easy to reproduce,just move the mouse
Now for your register dumps and information:
sr lo hi bad cause pc[...]
a004f413 000001b0 00000000 8009c6a0 80000028 7fff75b8
0x7fff75a0: li v0,4119
0x7fff75a4: syscall
So the pc is pointing just after the trampoline which suspiciously looks like the return of an old bug. Could your application be doing something unusual such as forking from a signal handler or similar? The scenario
around and click here and there then it would die. Will check this later,but I think such a giant as Xserver
won't fork frequently.
is aboutIf the new process touch the cow page first,shouldn't it get a new page and leave the original page for parent?
- kernel installs signal trampoline on stack
- kernel forks. Now the signal trampoline installed in the first step
resides on a copy-on-write page.
- newly created process touches the cow page, thereby resulting in
breaking of the cow page. Now parent and child have their own copy
of the page. BUT: flush_cache_page() doesn't properly flush this page
- Parent executes again on the copy of the page for which caches have
If so,the parent should be able to see the trampoline content from icache anyway(either L2 or memory should
have the value),though the child may not?
RM7000 has 16k 4-way set-associated primary caches,which are supposed to have no cache aliasing problemnot been flushed proplerly in the previous step, thereby failing to execute the trampoline - crash.
Bad news:
oops again:( while true; do fsck -y -f /dev/hda4 ; done
after about 5 succeeded run. So still some problems lurking somewhere.
It seems I have to switch some hardware...
Ralf
