linux-kernel - [PATCH 4.19 232/267] e1000e: Disable TSO for buffer overrun workaround

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-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200619141659.848204481@linuxfoundation.org>
Date:   Fri, 19 Jun 2020 16:33:37 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Kai-Heng Feng <kai.heng.feng@...onical.com>,
        Aaron Brown <aaron.f.brown@...el.com>,
        Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Subject: [PATCH 4.19 232/267] e1000e: Disable TSO for buffer overrun workaround

From: Kai-Heng Feng <kai.heng.feng@...onical.com>

commit f29801030ac67bf98b7a65d3aea67b30769d4f7c upstream.

Commit b10effb92e27 ("e1000e: fix buffer overrun while the I219 is
processing DMA transactions") imposes roughly 30% performance penalty.

The commit log states that "Disabling TSO eliminates performance loss
for TCP traffic without a noticeable impact on CPU performance", so
let's disable TSO by default to regain the loss.

CC: stable <stable@...r.kernel.org>
Fixes: b10effb92e27 ("e1000e: fix buffer overrun while the I219 is processing DMA transactions")
BugLink: https://bugs.launchpad.net/bugs/1802691
Signed-off-by: Kai-Heng Feng <kai.heng.feng@...onical.com>
Tested-by: Aaron Brown <aaron.f.brown@...el.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/net/ethernet/intel/e1000e/netdev.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -5251,6 +5251,10 @@ static void e1000_watchdog_task(struct w
 					/* oops */
 					break;
 				}
+				if (hw->mac.type == e1000_pch_spt) {
+					netdev->features &= ~NETIF_F_TSO;
+					netdev->features &= ~NETIF_F_TSO6;
+				}
 			}
 
 			/* enable transmits in the hardware, need to do this