4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Dumazet <[email protected]> [ 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 <[email protected]> Cc: Claudiu Manoil <[email protected]> Acked-by: Claudiu Manoil <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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 @@ -2951,7 +2951,7 @@ static bool gfar_add_rx_frag(struct gfar } /* 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 */
