Messages in this thread | | | Date | Mon, 28 Jul 2008 15:38:48 -0500 | From | Eric Sandeen <> | Subject | Re: [PATCH] eCryptfs - use page_alloc not kmalloc to get a page of memory |
| |
Andrew Morton wrote: > On Mon, 28 Jul 2008 11:13:03 -0500 > Eric Sandeen <sandeen@redhat.com> wrote: > >> With SLUB debugging turned on in 2.6.26, I was getting memory corruption >> when testing eCryptfs. The root cause turned out to be that eCryptfs >> was doing kmalloc(PAGE_CACHE_SIZE); virt_to_page() and treating that >> as a nice page-aligned chunk of memory. But at least with SLUB debugging >> on, this is not always true, and the page we get from virt_to_page does >> not necessarily match the PAGE_CACHE_SIZE worth of memory we got from >> kmalloc. >> >> My simple testcase was 2 loops doing "rm -f fileX; cp /tmp/fileX ." for >> 2 different multi-megabyte files. With this change I no longer see >> the corruption. > > The fix applies to both 2.6.25 and to 2.6.26 and appears to be needed > in both kernel versions, so I have tagged it for backporting into both.
I agree, thanks.
-Eric
| |