Re: UVM Fault

[Sarton O'Brien <bsd-xen%roguewrt.org@localhost>]

Manuel Bouyer wrote:
> On Mon, Jun 16, 2008 at 12:15:12PM +1000, Sarton O'Brien wrote:
> > On Sat, 14 Jun 2008 06:37:25 pm Mike Pumford wrote:
> > > John R. Shannon wrote:
> > > > Started happening immediately upon upgrade to 4.99.64:
> > > >
> > > > DOMU runs squid proxy. Repeatable fault occurs on forst web access via
> > > > squid. Works if previous 4.99.63 kernel is used in DOMU.
> > > Seeing something similar here on a quad core 4.99.64 on amd64.
> > Here's the trace with registers as requested:
> >
> >
> > Jun 16 12:04:59 squid[12711]: Squid Parent: child process 21641 started
> > uvm_fault(0xffffa000141a1720, 0x0, 1) -> e
> > fatal page fault in supervisor mode
> > trap type 6 code 0 rip ffffffff803a34a6 cs e030 rflags 10282 cr2  0 cpl 0 rsp 
> > ffffa00013be7810
> > kernel: page fault trap, code=0
> > Stopped in pid 16282.1 (pinger) at      netbsd:rb_tree_insert_node+0x26:        
> > m
> > ovq     0(%rax),%r14
> > rb_tree_insert_node() at netbsd:rb_tree_insert_node+0x26
> > uvm_pagealloc_strat() at netbsd:uvm_pagealloc_strat+0x2d2
>
> I've seen some commits from yamt@ about UVM and rb_tree. Maybe this is fixed
> now ...

No luck here. The domu fails to boot, now producing:

Starting cron.
Wed Jun 18 11:12:20 EST 2008
panic: kernel diagnostic assertion "!cv_has_waiters(&bp->b_done)" 
failed: file "/usr/src/sys/kern/vfs_subr2.c", line 551
fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip ffffffff80363c65 cs e030 rflags 246 cr2  ac4f44 
cpl 0 rsp ffffa00012bc0a70
Stopped in pid 0.4 (system) at  netbsd:breakpoint+0x5:  leave
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x255
__kernassert() at netbsd:__kernassert+0x2d
reassignbuf() at netbsd:reassignbuf+0x1a4
softdep_disk_write_complete() at netbsd:softdep_disk_write_complete+0x721
biodone2() at netbsd:biodone2+0x19
biointr() at netbsd:biointr+0x31
softint_thread() at netbsd:softint_thread+0x88
ds          0xa80
es          0xe02b
fs          0xa30
gs          0x207
rdi         0
rsi         0xd
rbp         0xffffa00012bc0a70
rbx         0xffffa00012bc0a80
rdx         0
rcx         0
rax         0x1
r8          0xffffffff805771c0  cpu_info_primary
r9          0x1
r10         0xffffa00012bc0990
r11         0xffffffff8037b640  xenconscn_putc
r12         0x100
r13         0xffffffff80467be0  copyright+0x88aa0
r14         0
r15         0x1
rip         0xffffffff80363c65  breakpoint+0x5
cs          0xe030
rflags      0x246
rsp         0xffffa00012bc0a70
ss          0xe02b
netbsd:breakpoint+0x5:  leave
db>

Updated about 20 mins ago.

Sarton