diff mbox

[net-2.6,2/3] igb: prevent skb_over panic w/ mtu smaller than 1K

Message ID 20090131005404.1466.30069.stgit@lost.foo-projects.org
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Kirsher, Jeffrey T Jan. 31, 2009, 12:54 a.m. UTC 
From: Alexander Duyck <alexander.h.duyck@intel.com>

A panic has been observed with frame sizes smaller than 1K.  This has been
root caused to the hardware spanning larger frames across multiple buffers
and then reporting the original frame size in the first descriptor.  To
prevent this we can enable set the LPE bit which in turn will restrict
packet sizes to those set in the RLPML register.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---

 drivers/net/igb/igb_main.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)


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

Comments

David Miller Jan. 31, 2009, 8:53 a.m. UTC | #1 
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Fri, 30 Jan 2009 16:54:04 -0800

> A panic has been observed with frame sizes smaller than 1K.  This has been
> root caused to the hardware spanning larger frames across multiple buffers
> and then reporting the original frame size in the first descriptor.  To
> prevent this we can enable set the LPE bit which in turn will restrict
> packet sizes to those set in the RLPML register.
> 
> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

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

Patch

diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index cc94412..a50db53 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -1834,11 +1834,11 @@  static void igb_setup_rctl(struct igb_adapter *adapter)
 	rctl |= E1000_RCTL_SECRC;
 
 	/*
-	 * disable store bad packets, long packet enable, and clear size bits.
+	 * disable store bad packets and clear size bits.
 	 */
-	rctl &= ~(E1000_RCTL_SBP | E1000_RCTL_LPE | E1000_RCTL_SZ_256);
+	rctl &= ~(E1000_RCTL_SBP | E1000_RCTL_SZ_256);
 
-	if (adapter->netdev->mtu > ETH_DATA_LEN)
+	/* enable LPE when to prevent packets larger than max_frame_size */
 		rctl |= E1000_RCTL_LPE;
 
 	/* Setup buffer sizes */
@@ -1864,7 +1864,7 @@  static void igb_setup_rctl(struct igb_adapter *adapter)
 	 */
 	/* allocations using alloc_page take too long for regular MTU
 	 * so only enable packet split for jumbo frames */
-	if (rctl & E1000_RCTL_LPE) {
+	if (adapter->netdev->mtu > ETH_DATA_LEN) {
 		adapter->rx_ps_hdr_size = IGB_RXBUFFER_128;
 		srrctl |= adapter->rx_ps_hdr_size <<
 			 E1000_SRRCTL_BSIZEHDRSIZE_SHIFT;