lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Sun, 30 Nov 2014 10:43:51 +0800
From:	Wei Yang <weiyang@...ux.vnet.ibm.com>
To:	netdev@...r.kernel.org
Cc:	davem@...emloft.net, gideonn@...lanox.com,
	Wei Yang <weiyang@...ux.vnet.ibm.com>,
	Eric Dumazet <edumazet@...gle.com>,
	Amir Vadai <amirv@...lanox.com>
Subject: [PATCH net] net/mlx4_en: correct the endianness of doorbell_qpn on big endian platform

In commit 6a4e812 (net/mlx4_en: Avoid calling bswap in tx fast path), we store
doorbell_qpn in big endian to avoid bswap(). Then we try to write it directly
by iowrite32() instead of iowrite32be().

This works fine on little endian platform, while has some problem on big
endian platform. Here is the definition in general:

	#define iowrite32(v, addr)	writel((v), (addr))
	#define writel(b,addr)		__raw_writel(__cpu_to_le32(b),addr)

On little endian platform, the value is not swapped before write. While on big
endian platform, the value is swapped. This is not expected to happen.

This patch does the swap on big endian platform before it is written.

Signed-off-by: Wei Yang <weiyang@...ux.vnet.ibm.com>
CC: Eric Dumazet <edumazet@...gle.com>
CC: Amir Vadai <amirv@...lanox.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_tx.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 454d9fe..76f028b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -954,7 +954,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 		tx_desc->ctrl.owner_opcode = op_own;
 		if (send_doorbell) {
 			wmb();
-			iowrite32(ring->doorbell_qpn,
+			iowrite32(__cpu_to_le32(ring->doorbell_qpn),
 				  ring->bf.uar->map + MLX4_SEND_DOORBELL);
 		} else {
 			ring->xmit_more++;
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists