4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit 69fed99baac186013840ced3524562841296034f ]
A driver using dev_alloc_page() must not reuse a page that had to
use emergency memory reserve.
Otherwise all packets using this page will be immediately dropped,
unless for very specific sockets having SOCK_MEMALLOC bit set.
This issue might be hard to debug, because only a fraction of the RX
ring buffer would suffer from drops.
Fixes: 75354148ce69 ("gianfar: Add paged allocation and Rx S/G")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Claudiu Manoil <claudiu.manoil@xxxxxxxxxxxxx>
Acked-by: Claudiu Manoil <claudiu.manoil@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/freescale/gianfar.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -2939,7 +2939,7 @@ static bool gfar_add_rx_frag(struct gfar
size, GFAR_RXB_TRUESIZE);
/* try reuse page */
- if (unlikely(page_count(page) != 1))
+ if (unlikely(page_count(page) != 1 || page_is_pfmemalloc(page)))
return false;
/* change offset to the other half */