Re: kernel panic: uvm_fault

[Thor Lancelot Simon <tls%panix.com@localhost>]

alloc_bouncebus?  On amd64?  I think you've got a trashed pointer
somewhere.

On Mon, Jan 26, 2015 at 02:47:55PM +0100, Thomas Klausner wrote:
> On Mon, Dec 22, 2014 at 03:56:43PM +0000, Robert Swindells wrote:
> > 
> > Thomas Klausner wrote:
> > >On Mon, Dec 22, 2014 at 03:29:58PM +0000, Robert Swindells wrote:
> > >> 
> > >> Thomas Klausner wrote:
> > >> >I had a kernel panic today with a amd64/7.99.3 kernel from Dec 20. The
> > >> >last activity I had started was downloading a file from network to an
> > >> >NFS directory mounted from a Synology.
> > 
> > >> It looks the same as the panic you had back in September to me:
> > >> 
> > >> <http://mail-index.netbsd.org/current-users/2014/09/13/msg025777.html>
> > >> 
> > >> Can you turn on HW checksumming on this machine ?
> > 
> > >I've just done that ("ifconfig wm0 tcp4csum ip4csum udp4csum"):
> > >
> > >wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
> > >	capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx>
> > >	capabilities=7ff80<TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx>
> > >	capabilities=7ff80<TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
> > >	enabled=3f00<IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx>
> > >	enabled=3f00<UDP4CSUM_Rx,UDP4CSUM_Tx>
> > >	ec_capabilities=7<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU>
> > >	ec_enabled=0
> > >...
> > >
> > >I had in the back of my memory that hardware checksumming was usually
> > >the cause of bugs, not when it's turned off. Am I misremembering?
> > 
> > Depends on the network controller, wm works well for me with
> > everything enabled.
> > 
> > wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
> >         capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx>
> >         capabilities=7ff80<TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx>
> >         capabilities=7ff80<TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
> >         enabled=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx>
> >         enabled=7ff80<TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx>
> >         enabled=7ff80<TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
> >         ec_capabilities=7<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU>
> >         ec_enabled=0
> > 
> > I have had similar crashes to you when using sw checksumming on
> > amd64, never seen it on i386 or arm.
> > 
> > There was also this:
> > 
> > <http://mail-index.netbsd.org/port-sparc64/2014/11/29/msg002298.html>
> > 
> > I guess we need to add some more KASSERT() checks.
> 
> Ok, the Synology installed an opsys update again last night, and a
> couple minutes ago I tried writing to a still-mounted file system from
> it. And got a panic. From dmesg:
> 
> 192.168.1.2:/volume1/roms: re-enabling wcc
> 192.168.1.2:/volume1/video: re-enabling wcc
> panic: _bus_virt_to_bus
> cpu1: Begin traceback...
> vpanic() at netbsd:vpanic+0x13c
> snprintf() at netbsd:snprintf
> _bus_dma_alloc_bouncebuf() at netbsd:_bus_dma_alloc_bouncebuf
> bus_dmamap_load_mbuf() at netbsd:bus_dmamap_load_mbuf+0xf0
> wm_nq_start() at netbsd:wm_nq_start+0x1c5
> ifq_enqueue() at netbsd:ifq_enqueue+0xae
> ether_output() at netbsd:ether_output+0x579
> ip_output() at netbsd:ip_output+0xdeb
> tcp_output() at netbsd:tcp_output+0x15cf
> tcp_send_wrapper() at netbsd:tcp_send_wrapper+0xa2
> sosend() at netbsd:sosend+0x712
> nfs_send() at netbsd:nfs_send+0x8e
> nfs_request() at netbsd:nfs_request+0x39d
> nfs_writerpc() at netbsd:nfs_writerpc+0x3b0
> nfs_doio() at netbsd:nfs_doio+0x250
> nfssvc_iod() at netbsd:nfssvc_iod+0x1a1
> cpu1: End traceback...
> 
> 
> I had and still have all the checksum options turned on as you
> suggested.
> 
> wm0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>         capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx>
>         capabilities=7ff80<TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx>
>         capabilities=7ff80<TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
>         enabled=3ff00<IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx>
>         enabled=3ff00<UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx,TCP6CSUM_Tx>
>         enabled=3ff00<UDP6CSUM_Rx,UDP6CSUM_Tx>
>         ec_capabilities=7<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU>
>         ec_enabled=0
>  
> At least the backtrace looks nfs related this time :)
>  Thomas

-- 
 Thor Lancelot Simon	                                      tls%panix.com@localhost
"From the tooth paste you use in the morning to the salt on your evening meal,
it's easy to take for granted the many products brought to us with explosives."
    - Institute of Manufacturers of Explosives, "Explosives Make It Possible"