misc/107277: panic: bus_dmamap_load_mbuf_sg

[Andrea Campi]

>Number:         107277
>Category:       misc
>Synopsis:       panic: bus_dmamap_load_mbuf_sg
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Dec 28 13:30:14 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Andrea Campi
>Release:        FreeBSD 6.2-RC2
>Organization:
Sourcesense
>Environment:
FreeBSD gw0.webcom.it 6.2-PRERELEASE FreeBSD 6.2-PRERELEASE #0: Wed Dec 27 12:47:29 UTC 2006
(it says prerelease but no more commits happened before RC2 was tagged)
>Description:
panic: bus_dmamap_load_mbuf_sg: no mbuf packet header!
KDB: stack backtrace:
panic(c06128c3,c060f93c,c055b9af,c0db804e,c0db803e,...) at panic+0xef
bus_dmamap_load_mbuf_sg(c0d18e00,0,c0db8000,c0d627d8,c0d627b8,1) at
bus_dmamap_load_mbuf_sg+0x4ec   ath_start(c0d55000,35000,36,0,c1000000,...) at
ath_start+0x26f
ether_output_frame(c0d55000,c0fee600,c1000006,0,1,...) at
ether_output_frame+0x226
ether_output(c0d55000,c0fee600,c56f6bb0,c0feb840) at ether_output+0x2de
ip_output(c0fee600,0,c56f6bac,1,0,0) at ip_output+0xaad
ip_forward(c0cf9648,c56f6c78,c04e14dd,c066ca40,1,...) at ip_forward+0x120
ip_input(c0fee600,18,c0673378,c56f6cec,c0541fd7,...) at ip_input+0x8d5
netisr_processqueue(c0d12240,c0cef400,0,c56f6d0c,c04bd93b,...) at
netisr_processqueue+0x13
swi_net(0,c0cef438,c0cfaa80,c04bd740,c0cf9648,...) at swi_net+0x97
ithread_loop(c0ce8750,c56f6d38,c0ce8750,c04bd740,0,...) at ithread_loop+0x1fb
fork_exit(c04bd740,c0ce8750,c56f6d38) at fork_exit+0x83
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xc56f6d6c, ebp = 0 ---
KDB: enter: panic
[thread pid 13 tid 100003 ]
Stopped at      kdb_enter+0x2c: leal    0(%esi),%esi
>How-To-Repeat:
Happens every 12-24 hours while forwarding regular traffic (no ifconfig at the moment, etc). Happens both with hostapd running and without.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: