On Sat, Feb 13, 2016 at 03:42:16PM +1100, Jonathan Gray wrote:
> On Fri, Feb 12, 2016 at 11:07:35AM -0500, Johan Huldtgren wrote:
> > uvm_fault(0xffffffff8193f240, 0x38, 0, 1) -> e
> > kernel: page fault trap, code=0
> > Stopped at sr_validate_io+0x36: movl 0x38(%r9),%r10d
> > ddb{1}> trace
> > sr_validate_io() at sr_validate_io+0x36
> > sr_raid5_rw() at sr_raid5_rw+0x40
> > sr_raid_recreate_wu() at sr_raid_recreate_wu+0x2c
> > sr_wu_done_callback() at sr_wu_done_callback+0x17a
> > taskq_thread() at taskq_thread+0x6c
>
> Thanks for all the detail you've provided here. The fault appears to be
> caused by a NULL xs. A diff to error in that case is provided below.
>
> Perhaps someone familiar with the softraid/scsi code can comment as to
> why this is occuring.
The trace of the first crash reported by Johan looks like it could perhaps
be caused by a garbage xs, doesn't it?
Quoting http://marc.info/?l=openbsd-misc&m=145477770306396&w=2
panic: Non dma-reachable buffer at curaddr 0xffffffff81115888(raw)
Stopped at Debugger+0x9: leave
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*25637 25637 0 0x14000 0x200 1 srdis
Debugger() at Debugger+0x9
panic() at panic+0xfe
_bus_dmamap_load_buffer() at _bus_dmamap_load_buffer+0x1b6
_bus_dmamap_load() at _bus_dmamap_load+0x7f
ahci_load_prdt() at ahci_load_prdt+0x97
ahci_ata_cmd() at ahci_ata_cmd+0x69
atascsi_disk_cmd() at atascsis_disk_cmd+0x1b1
scsi_xs_exec() scsi_xs_exec+0x35
sdstart() at sdstart+0x16f
scsi_iopool_run() at scsi_iopool_run+0x5d
scsi_xsh_runqueue() at scsi_xsh_runqueue+0x13d
scsi_xsh_add() at scsi_xsh_add+0x98
sdstrategy() at sdstrategy+0x10f
spec_strategy() at spec_strategy+0x53
end trace frame: 0xffff800032ca1e40, count: 0
Maybe there's an uninitialized variable which happened to contain
zeros in this second instance of the crash?
> Index: sys/dev/softraid.c
> ===================================================================
> RCS file: /cvs/src/sys/dev/softraid.c,v
> retrieving revision 1.365
> diff -u -p -r1.365 softraid.c
> --- sys/dev/softraid.c 29 Dec 2015 04:46:28 -0000 1.365
> +++ sys/dev/softraid.c 13 Feb 2016 04:35:39 -0000
> @@ -4545,6 +4545,9 @@ sr_validate_io(struct sr_workunit *wu, d
> struct scsi_xfer *xs = wu->swu_xs;
> int rv = 1;
>
> + if (xs == NULL)
> + goto bad;
> +
> DNPRINTF(SR_D_DIS, "%s: %s 0x%02x\n", DEVNAME(sd->sd_sc), func,
> xs->cmd->opcode);
>
>
