Messages in this thread |  | | Date | Mon, 10 May 2010 21:05:59 +0200 | | From | Andrea Arcangeli <> | | Subject | Re: [PATCH 2/2] mm,migration: Avoid race between shift_arg_pages() and rmap_walk() during migration by not migrating temporary stacks |
| |
On Mon, May 10, 2010 at 12:41:07PM -0500, Christoph Lameter wrote: > A simple way to disallow migration of pages is to increment the refcount > of a page.
Ok for migrate but it won't prevent to crash in split_huge_page rmap walk, nor the PG_lock. Why for a rmap bug have a migrate specific fix? The fix that makes execve the only special place to handle in every rmap walk, is at least more maintainable than a fix that makes one of the rmap walk users special and won't fix the others, as there will be more than just 1 user that requires this. My fix didn't make execve special and it didn't require execve knowledge into the every rmap walk like migrate (split_huge_page etc...) but as long as the kernel doesn't crash I'm fine ;).
|  |