dma_pin_iovec_pages() eventually causes the page allocator to stumble across it warning case when a request for contigous mem block gets order >= MAX_ORDER. trinity(11230): Randomness reseeded to 0xaf76756f trinity: trinity(11230) Randomness reseeded to 0xaf76756f [ 7442.617160] ------------[ cut here ]------------ [ 7442.621890] WARNING: at mm/page_alloc.c:2410 __alloc_pages_nodemask+0x346/0xa00() ... [ 7442.797088] Call Trace: [ 7442.799614] [<ffffffff81600bf7>] dump_stack+0x19/0x1b [ 7442.804860] [<ffffffff8105f621>] warn_slowpath_common+0x61/0x80 [ 7442.810944] [<ffffffff8105f6fa>] warn_slowpath_null+0x1a/0x20 [ 7442.816858] [<ffffffff8113d016>] __alloc_pages_nodemask+0x346/0xa00 [ 7442.823294] [<ffffffff81175f59>] alloc_pages_current+0xa9/0x170 [ 7442.829364] [<ffffffff811384be>] __get_free_pages+0xe/0x50 [ 7442.835009] [<ffffffff8118064e>] kmalloc_order_trace+0x2e/0xa0 [ 7442.841005] [<ffffffff81182899>] __kmalloc+0x219/0x230 [ 7442.846284] [<ffffffff81387c8b>] dma_pin_iovec_pages+0x9b/0x240 [ 7442.852323] [<ffffffff8153ffb8>] tcp_recvmsg+0x888/0xd10 ... dma_pin_iovec_pages() is actually being used for an unique callsite within tcp_recvmsg() which falls back to skb_copy_datagram_iovec() if the first routine fails to pin a DMA buffer for the iovec. The splatted calltrace is more scary than other thing, so lets just prevent it from getting out to the wild world. This patch also does a minor code style surgery on the surrounding hunk. Signed-off-by: Rafael Aquini <aquini@xxxxxxxxxx> --- drivers/dma/iovlock.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/dma/iovlock.c b/drivers/dma/iovlock.c index bb48a57..4cb8379 100644 --- a/drivers/dma/iovlock.c +++ b/drivers/dma/iovlock.c @@ -69,9 +69,10 @@ struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len) } while (iovec_len_used < len); /* single kmalloc for pinned list, page_list[], and the page arrays */ - local_list = kmalloc(sizeof(*local_list) - + (nr_iovecs * sizeof (struct dma_page_list)) - + (iovec_pages_used * sizeof (struct page*)), GFP_KERNEL); + local_list = kmalloc(sizeof(*local_list) + + (nr_iovecs * sizeof(struct dma_page_list)) + + (iovec_pages_used * sizeof(struct page *)), + GFP_KERNEL | __GFP_NOWARN); if (!local_list) goto out; -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
