From: Zlatko Calusic <[email protected]> The unintended consequence of commit 4ae0a48b is that wait_iff_congested() can now be called with NULL struct zone* producing kernel oops like this:
BUG: unable to handle kernel NULL pointer dereference IP: [<ffffffff811542d9>] wait_iff_congested+0x59/0x140 This trivial patch fixes it. Reported-by: Zhouping Liu <[email protected]> Reported-and-tested-by: Sedat Dilek <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Hugh Dickins <[email protected]> Signed-off-by: Zlatko Calusic <[email protected]> --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 02bcfa3..e55ce55 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2782,7 +2782,7 @@ loop_again: if (total_scanned && (sc.priority < DEF_PRIORITY - 2)) { if (has_under_min_watermark_zone) count_vm_event(KSWAPD_SKIP_CONGESTION_WAIT); - else + else if (unbalanced_zone) wait_iff_congested(unbalanced_zone, BLK_RW_ASYNC, HZ/10); } -- 1.8.1.rc3 -- Zlatko -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
