---876492614-694105881-901118249=:440
Content-Type: TEXT/PLAIN; charset=US-ASCII
On Fri, 17 Jul 1998, Itai Nahshon wrote:
> 1. I sent a similar report some time ago.. the panic still happens.
> The problem is when unmapping the last part (but not all) of
> a segment acquired by shmget + shmat. Ref count goes down to 0
> and then the segment is reused!!
Hi Folks,
I've attached an oops for _real_ hackers to examine. Patch follows.
It should illuminate the problem, and at least does stop the oops.
<CRINGE>
--- linux-2.1.111-pre1/ipc/shm.c.org Wed Jul 22 13:07:27 1998
+++ linux-2.1.111-pre1/ipc/shm.c Wed Jul 22 15:56:50 1998
@@ -626,7 +626,12 @@
remove_attach(shp,shmd); /* remove from shp->attaches */
shp->shm_lpid = current->pid;
shp->shm_dtime = CURRENT_TIME;
- if (--shp->shm_nattch <= 0 && shp->shm_perm.mode & SHM_DEST)
+ /* FIXME: If vm_end = vm_start, we are doing unmap_fixup().
+ * This is very fragile and stupid. It's also the best I
+ * could come up with without special casing unmap_fixup().
+ */
+ if (--shp->shm_nattch <= 0 && shp->shm_perm.mode & SHM_DEST
+ && shmd->vm_end != shmd->vm_start)
killseg (id);
}
</CRINGE>
We accept VISA, MASTERCARD, cool ideas...
Energize Scotty! ;-)
-Mike
---876492614-694105881-901118249=:440
Content-Type: TEXT/PLAIN; charset=US-ASCII; name=shm_oops
Content-Transfer-Encoding: BASE64
Content-ID: <Pine.LNX.3.95.980722163729.440B@mikeg.weiden.de>
Content-Description: the oops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---876492614-694105881-901118249=:440--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html