Re: [Feature Request?] Inline compression of process core dumps

Andi Kleen
2007-04-13T11:26:08Z

Alan Cox <alan@lxorguk.ukuu.org.uk> writes:

> > I saw that too, and unfortunately I don't know what what that condition
> > represents, either. It's the only other element in that if statement
> > that could make it take that path, so I'm assuming that's part of the
> > problem.
>
> Multiple mm's mean multiple threads with a different set of mappings,
> which would fit for UML. Either way there should be a check for !pipe
> before appending the pid

Here's a patch. It just doesn't do any formatting for the pipe case.

-Andi

Fix core to pipe for multithreaded processes

I also removed the BKL around format_corename because it seems unneeded.

Signed-off-by: Andi Kleen <ak@suse.de>

Index: linux-2.6.21-rc3-test/fs/exec.c
===================================================================
--- linux-2.6.21-rc3-test.orig/fs/exec.c
+++ linux-2.6.21-rc3-test/fs/exec.c
@@ -1501,9 +1501,6 @@ int do_coredump(long signr, int exit_cod
* lock_kernel() because format_corename() is controlled by sysctl, which
* uses lock_kernel()
*/
- lock_kernel();
- format_corename(corename, core_pattern, signr);
- unlock_kernel();
if (corename[0] == '|') {
/* SIGPIPE can happen, but it's just never processed */
if(call_usermodehelper_pipe(corename+1, NULL, NULL, &file)) {
@@ -1512,10 +1509,12 @@ int do_coredump(long signr, int exit_cod
goto fail_unlock;
}
ispipe = 1;
- } else
+ } else {
+ format_corename(corename, core_pattern, signr);
file = filp_open(corename,
O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
0600);
+ }
if (IS_ERR(file))
goto fail_unlock;
inode = file->f_path.dentry->d_inode;