From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Halasa Subject: TCP stalls, 2.6.12pre6 Date: Fri, 10 Jun 2005 00:58:55 +0200 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: To: Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org Hi, I got this three times recently, with 2.6.12 pre6 and possibly pre5 (4?) kernels on both sides: intrepid is X11-server with ssh connection to defiant (X11-forwarding, EPIC100 PCI NIC). defiant is an older notebook machine and it was running XEmacs and Firefox with ssh/X11 (cardbus DEC 21143). Both on the same Ethernet subnet. Both standard MTU etc. intrepid# netstat -to tcp 0 0 intrepid:3457 defiant:ssh ESTABLISHED keepalive (5615.71/0/0) defiant# netstat -to (not 100% sure about this data) Send-Q tcp 0 32800 defiant:ssh intrepid:3457 ESTABLISHED keepalive (20.5/0/0) Partial dump: intrepid# tcpdump -r qwe -vve port not 4840 00:08:32.603003 len 1514: IP (tos 0x10, ttl 64, id 17467, offset 0, flags [DF], proto 6, length: 1500) defiant.ssh > intrepid.3457: . [bad tcp cksum 2fa (->8fbe)!] 2999401769:2999403217(1448) ack 1597770543 win 16022 00:08:55.750326 len 158: IP (tos 0x10, ttl 64, id 13187, offset 0, flags [DF], proto 6, length: 144) intrepid.3457 > defiant.ssh: P [tcp sum ok] 1:81(80) ack 0 win 18856 00:08:55.750603 len 66: IP (tos 0x10, ttl 64, id 17469, offset 0, flags [DF], proto 6, length: 52) defiant.ssh > intrepid.3457: . [tcp sum ok] 16816:16816(0) ack 81 win 16022 Send-Q is stuck at the fixed value. Other TCP connections (including similar ones between the two hosts) are not affected. Ideas? -- Krzysztof Halasa