On Thu, Oct 01, 2009 at 09:56:04PM +0200, Rafael J. Wysocki wrote:
> Bug-Entry     : http://bugzilla.kernel.org/show_bug.cgi?id=14265
> Subject               : ifconfig: page allocation failure. order:5, 
> mode:0x8020 w/ e100
> Submitter     : Karol Lewandowski <[email protected]>
> Date          : 2009-09-15 12:05 (17 days old)
> References    : http://marc.info/?l=linux-kernel&m=125301636509517&w=4

Guys, could anyone check if patch below helps?  I think I've finally
found culprit of all allocation failures (but I might be wrong
too... ;-)

Thanks.


commit d6849591e042bceb66f1b4513a1df6740d2ad762
Author: Karol Lewandowski <[email protected]>
Date:   Wed Oct 21 21:01:20 2009 +0200

    SLUB: Don't drop __GFP_NOFAIL completely from allocate_slab()
    
    Commit ba52270d18fb17ce2cf176b35419dab1e43fe4a3 unconditionally
    cleared __GFP_NOFAIL flag on all allocations.
    
    Preserve this flag on second attempt to allocate page (with possibly
    decreased order).
    
    This should help with bugs #14265, #14141 and similar.
    
    Signed-off-by: Karol Lewandowski <[email protected]>

diff --git a/mm/slub.c b/mm/slub.c
index b627675..ac5db65 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1084,7 +1084,7 @@ static struct page *allocate_slab(struct kmem_cache *s, 
gfp_t flags, int node)
 {
        struct page *page;
        struct kmem_cache_order_objects oo = s->oo;
-       gfp_t alloc_gfp;
+       gfp_t alloc_gfp, nofail;
 
        flags |= s->allocflags;
 
@@ -1092,6 +1092,7 @@ static struct page *allocate_slab(struct kmem_cache *s, 
gfp_t flags, int node)
         * Let the initial higher-order allocation fail under memory pressure
         * so we fall-back to the minimum order allocation.
         */
+       nofail = flags & __GFP_NOFAIL;
        alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
 
        page = alloc_slab_page(alloc_gfp, node, oo);
@@ -1100,8 +1101,10 @@ static struct page *allocate_slab(struct kmem_cache *s, 
gfp_t flags, int node)
                /*
                 * Allocation may have failed due to fragmentation.
                 * Try a lower order alloc if possible
+                *
+                * Preserve __GFP_NOFAIL flag if previous allocation failed.
                 */
-               page = alloc_slab_page(flags, node, oo);
+               page = alloc_slab_page(flags | nofail, node, oo);
                if (!page)
                        return NULL;
 
--
To unsubscribe from this list: send the line "unsubscribe kernel-testers" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to