alpha and em mtu

[John Baldwin]

On Friday 19 November 2004 04:32 am, Sten Spans wrote:
> On Mon, 15 Nov 2004, Sten Spans wrote:
> > On Mon, 15 Nov 2004, John Baldwin wrote:
> >> On Monday 15 November 2004 04:07 pm, Sten Spans wrote:
> >>> On Mon, 15 Nov 2004, John Baldwin wrote:
> >>>
> >>> changed to ((off0 & 0x3) != 0), didn't seem to print anything.
> >>
> >> Ok, try this one then instead:
> >>
> >> Index: netinet/tcp_input.c
> >> ===================================================================
> >> RCS file: /usr/cvs/src/sys/netinet/tcp_input.c,v
> >> retrieving revision 1.255
> >> diff -u -r1.255 tcp_input.c
> >> --- netinet/tcp_input.c	7 Nov 2004 19:19:35 -0000	1.255
> >> +++ netinet/tcp_input.c	15 Nov 2004 21:19:50 -0000
> >> @@ -504,6 +504,8 @@
> >> 			}
> >> 		}
> >> 		ip = mtod(m, struct ip *);
> >> +		if (((uintptr_t)ip & 0x3) != 0)
> >> +			printf("%s: ip %p is misaligned\n", __func__, ip);
> >> 		ipov = (struct ipovly *)ip;
> >> 		th = (struct tcphdr *)((caddr_t)ip + off0);
> >> 		tlen = ip->ip_len;
> >
> > This does print something:
> > deepthought# ifconfig em0 mtu 1501
> > deepthought# tcp_input: ip 0xfffffc001817f00e is misaligned
> >
> > fatal kernel trap:
> >
> >    trap entry     = 0x4 (unaligned access fault)
> >    faulting va    = 0xfffffc001817f02e
> >    opcode         = 0x28
> >    register       = 0x1
> >    pc             = 0xfffffc00004cd134
> >    ra             = 0xfffffc00004ccf94
> >    sp             = 0xfffffe00187a9af0
> >    curthread      = 0xfffffc001f3a70e0
> >        pid = 14, comm = swi1: net
> >
> > [thread 100006]
> > Stopped at      tcp_input+0x3a4:        srl     t0,#0x2,t0      <t0=0x45>
> >
> >
> > The ip's used are 192.168.1.3 and 192.168.1.4.
>
> Any luck or should I turn this into a pr ?

Sorry, been busy recently.  A PR certainly wouldn't hurt.  Does this panic go 
away if you use a different MTU btw?


-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org