Messages in this thread | | | Date | Mon, 28 Jul 2008 13:35:04 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH] eCryptfs - use page_alloc not kmalloc to get a page of memory |
| |
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.
| |