[PATCH 4.1 15/43] atl1c: Improve driver not to do order 4 GFP_ATOMIC allocation

From: Greg Kroah-Hartman
Date: Wed Jan 20 2016 - 18:23:17 EST


4.1-stable review patch. If anyone has any objections, please let me know.

------------------

From: Pavel Machek <pavel@xxxxxx>

[ Upstream commit f2a3771ae8aca879c32336c76ad05a017629bae2 ]

atl1c driver is doing order-4 allocation with GFP_ATOMIC
priority. That often breaks networking after resume. Switch to
GFP_KERNEL. Still not ideal, but should be significantly better.

atl1c_setup_ring_resources() is called from .open() function, and
already uses GFP_KERNEL, so this change is safe.

Signed-off-by: Pavel Machek <pavel@xxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/atheros/atl1c/atl1c_main.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
@@ -1014,13 +1014,12 @@ static int atl1c_setup_ring_resources(st
sizeof(struct atl1c_recv_ret_status) * rx_desc_count +
8 * 4;

- ring_header->desc = pci_alloc_consistent(pdev, ring_header->size,
- &ring_header->dma);
+ ring_header->desc = dma_zalloc_coherent(&pdev->dev, ring_header->size,
+ &ring_header->dma, GFP_KERNEL);
if (unlikely(!ring_header->desc)) {
- dev_err(&pdev->dev, "pci_alloc_consistend failed\n");
+ dev_err(&pdev->dev, "could not get memory for DMA buffer\n");
goto err_nomem;
}
- memset(ring_header->desc, 0, ring_header->size);
/* init TPD ring */

tpd_ring[0].dma = roundup(ring_header->dma, 8);