From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steffen Klassert Subject: xfrm: warning on negative dst refcount Date: Fri, 4 Jun 2010 12:40:12 +0200 Message-ID: <20100604104012.GA13408@secunet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: Eric Dumazet , David Miller Return-path: Received: from a.mx.secunet.com ([195.81.216.161]:51014 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753915Ab0FDKkr (ORCPT ); Fri, 4 Jun 2010 06:40:47 -0400 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: I see the warning below frequently when I'm running iperf on a IPsec connection. It seems that dst_pop() drops a refcount on a noref dst_entry. I was able to fix this by changing dst_pop() to a new function skb_dst_pop() which uses skb_dst_drop(skb) instead of dst_release(dst) to drop the reference if necessary. I'll send the patch that fixed the issue for me in repy to this mail. I don't know that much about the noref work, so I'm not sure whether this is the right fix, but I got rid of the warning at least. Steffen Jun 4 10:21:24 mainline kernel: [ 1334.203913] WARNING: at /home/secunet/git/linux-sinafe-2.6/net/core/dst.c:276 xfrm_output_resume+0x2d3/0x35e() Jun 4 10:21:24 mainline kernel: [ 1334.203915] Hardware name: Jun 4 10:21:24 mainline kernel: [ 1334.203916] Modules linked in: authenc esp4 xfrm4_mode_tunnel aes_x86_64 aes_generic cbc sha1_generic xfrm_user ipv6 acpi_cpufreq mperf cpufreq_userspace cpufreq_stats cpufreq_ondemand freq_table cpufreq_conservative cpufreq_powersave container fan video output sbs sbshc battery af_packet ac fuse loop option usb_wwan usbserial sr_mod cdrom iTCO_wdt ehci_hcd thermal uhci_hcd serio_raw psmouse tpm_tis tpm tpm_bios iTCO_vendor_support pcspkr processor thermal_sys evdev usbcore button ata_generic Jun 4 10:21:24 mainline kernel: [ 1334.203944] Pid: 3337, comm: dd Tainted: G W 2.6.35-rc1+ #276 Jun 4 10:21:24 mainline kernel: [ 1334.203946] Call Trace: Jun 4 10:21:24 mainline kernel: [ 1334.203947] [] ? xfrm_output_resume+0x2d3/0x35e Jun 4 10:21:24 mainline kernel: [ 1334.203952] [] ? xfrm_output_resume+0x2d3/0x35e Jun 4 10:21:24 mainline kernel: [ 1334.203955] [] ? warn_slowpath_common+0x78/0x8d Jun 4 10:21:24 mainline kernel: [ 1334.203958] [] ? xfrm_output_resume+0x2d3/0x35e Jun 4 10:21:24 mainline kernel: [ 1334.203961] [] ? ip_queue_xmit+0x2bc/0x304 Jun 4 10:21:24 mainline kernel: [ 1334.203964] [] ? tcp_transmit_skb+0x6d2/0x701 Jun 4 10:21:24 mainline kernel: [ 1334.203967] [] ? tcp_cong_avoid+0xe/0x1d Jun 4 10:21:24 mainline kernel: [ 1334.203970] [] ? tcp_fin+0x74/0x17c Jun 4 10:21:24 mainline kernel: [ 1334.203972] [] ? tcp_data_queue+0x2fc/0xb64 Jun 4 10:21:24 mainline kernel: [ 1334.203975] [] ? tcp_rcv_state_process+0x927/0x99b Jun 4 10:21:24 mainline kernel: [ 1334.203978] [] ? tcp_v4_do_rcv+0x18b/0x1d0 Jun 4 10:21:24 mainline kernel: [ 1334.203981] [] ? tcp_v4_rcv+0x485/0x721 Jun 4 10:21:24 mainline kernel: [ 1334.203985] [] ? ip_local_deliver+0xda/0x165 Jun 4 10:21:24 mainline kernel: [ 1334.203988] [] ? ip_rcv+0x515/0x53d Jun 4 10:21:24 mainline kernel: [ 1334.203991] [] ? process_backlog+0x99/0x174 Jun 4 10:21:24 mainline kernel: [ 1334.203994] [] ? net_rx_action+0xab/0x153 Jun 4 10:21:24 mainline kernel: [ 1334.203997] [] ? __do_softirq+0x8d/0x107 Jun 4 10:21:24 mainline kernel: [ 1334.204000] [] ? call_softirq+0x1c/0x28 Jun 4 10:21:24 mainline kernel: [ 1334.204003] [] ? do_softirq+0x31/0x64 Jun 4 10:21:24 mainline kernel: [ 1334.204005] [] ? irq_exit+0x36/0x78 Jun 4 10:21:24 mainline kernel: [ 1334.204008] [] ? do_IRQ+0xa7/0xbd Jun 4 10:21:24 mainline kernel: [ 1334.204011] [] ? ret_from_intr+0x0/0xa Jun 4 10:21:24 mainline kernel: [ 1334.204012] [] ? _raw_spin_unlock_irqrestore+0x4/0x5 Jun 4 10:21:24 mainline kernel: [ 1334.204018] [] ? pipe_write+0x413/0x447 Jun 4 10:21:24 mainline kernel: [ 1334.204021] [] ? do_sync_write+0xb3/0xf7 Jun 4 10:21:24 mainline kernel: [ 1334.204024] [] ? kmsg_read+0x44/0x4e Jun 4 10:21:24 mainline kernel: [ 1334.204027] [] ? schedule+0x525/0x5db Jun 4 10:21:24 mainline kernel: [ 1334.204030] [] ? vfs_write+0xad/0x149 Jun 4 10:21:24 mainline kernel: [ 1334.204033] [] ? sys_write+0x45/0x6e Jun 4 10:21:24 mainline kernel: [ 1334.204035] [] ? system_call_fastpath+0x16/0x1b Jun 4 10:21:24 mainline kernel: [ 1334.204037] ---[ end trace ab41f96596a62e77 ]---