Commit 8269730b authored by Andi Kleen's avatar Andi Kleen Committed by Jens Axboe
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[BLOCK] Fix bounce limit address check 



Do a safer check for when to enable DMA. Currently we enable ISA DMA
for cases that do not need it, resulting in OOM conditions when ZONE_DMA
runs out of space.

Signed-off-by: default avatarJens Axboe <axboe@suse.de>
parent dd67d051

block/ll_rw_blk.c

+1 −1
Original line number Diff line number Diff line
@@ -638,7 +638,7 @@ void blk_queue_bounce_limit(request_queue_t *q, u64 dma_addr) 
	/* Assume anything <= 4GB can be handled by IOMMU.

	   Actually some IOMMUs can handle everything, but I don't

	   know of a way to test this here. */

	if (bounce_pfn < (0xffffffff>>PAGE_SHIFT))

	if (bounce_pfn < (min_t(u64,0xffffffff,BLK_BOUNCE_HIGH) >> PAGE_SHIFT))

		dma = 1;

	q->bounce_pfn = max_low_pfn;

#else