netdev - [net] ixgbe: fix panic while dumping packets on Tx hang with IOMMU

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 linux-cve-announce 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]

Message-Id: <1343301684-10158-1-git-send-email-jeffrey.t.kirsher@intel.com>
Date:	Thu, 26 Jul 2012 04:21:24 -0700
From:	Jeff Kirsher <jeffrey.t.kirsher@...el.com>
To:	davem@...emloft.net
Cc:	Emil Tantilov <emil.s.tantilov@...el.com>, netdev@...r.kernel.org,
	gospo@...hat.com, sassmann@...hat.com,
	Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Subject: [net] ixgbe: fix panic while dumping packets on Tx hang with IOMMU

From: Emil Tantilov <emil.s.tantilov@...el.com>

This patch resolves a "BUG: unable to handle kernel paging request at ..."
oops while dumping packet data. The issue occurs with IOMMU enabled due to
the address provided by phys_to_virt().

This patch makes use of skb->data on Tx and the virtual address of the pages
allocated for Rx.

Signed-off-by: Emil Tantilov <emil.s.tantilov@...el.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@...el.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 3b6784c..c709eae 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -396,11 +396,10 @@ static void ixgbe_dump(struct ixgbe_adapter *adapter)
 				pr_cont("\n");
 
 			if (netif_msg_pktdata(adapter) &&
-			    dma_unmap_len(tx_buffer, len) != 0)
+			    tx_buffer->skb)
 				print_hex_dump(KERN_INFO, "",
 					DUMP_PREFIX_ADDRESS, 16, 1,
-					phys_to_virt(dma_unmap_addr(tx_buffer,
-								    dma)),
+					tx_buffer->skb->data,
 					dma_unmap_len(tx_buffer, len),
 					true);
 		}
@@ -474,10 +473,12 @@ rx_ring_summary:
 					(u64)rx_buffer_info->dma,
 					rx_buffer_info->skb);
 
-				if (netif_msg_pktdata(adapter)) {
+				if (netif_msg_pktdata(adapter) &&
+				    rx_buffer_info->dma) {
 					print_hex_dump(KERN_INFO, "",
 					   DUMP_PREFIX_ADDRESS, 16, 1,
-					   phys_to_virt(rx_buffer_info->dma),
+					   page_address(rx_buffer_info->page) +
+						    rx_buffer_info->page_offset,
 					   ixgbe_rx_bufsz(rx_ring), true);
 				}
 			}
-- 
1.7.11.2

--
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