Re: KASSERT umap->refcount != 0 failed (sys/uvm/uvm_bio.c:248)

[Nicolas Joly <njoly%pasteur.fr@localhost>]

On Fri, Apr 30, 2010 at 05:52:29PM +0100, Mindaugas Rasiukevicius wrote:
> Hello,
> 
> Nicolas Joly <njoly%pasteur.fr@localhost> wrote:
> > While stress testing the network interfaces on a new -current
> > NetBSD/amd64 server which has 64GB of ram, the following KASSERT
> > fired:
> > 
> > panic: kernel diagnostic assertion "umap->refcount != 0" failed: file
> > "/local/src/NetBSD/src/sys/uvm/uvm_bio.c", line 248 fatal breakpoint trap
> > in supervisor mode trap type 1 code 0 rip ffffffff80229d65 cs 8 rflags 246
> > cr2  ffff8000d1c21000 cpl 0 rsp ffff8000d2c87430 Stopped in pid 496.1 (dd)
> > at    netbsd:breakpoint+0x5:  leave db{0}> bt
> > breakpoint() at netbsd:breakpoint+0x5
> > panic() at netbsd:panic+0x2ba
> > kern_assert() at netbsd:kern_assert+0x2d
> > ubc_fault() at netbsd:ubc_fault+0x4c9
> > uvm_fault_internal() at netbsd:uvm_fault_internal+0x469
> > trap() at netbsd:trap+0x702
> > --- trap (number 0) ---
> 
> Weird.  What other CPUs do?

Most of them are idle ...

db{3}> mach cpu 0
using CPU 0
db{3}> bt
_kernel_lock() at netbsd:_kernel_lock+0xcd
intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x16
Xintr_ioapic_level6() at netbsd:Xintr_ioapic_level6+0xf4
--- interrupt ---
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193

db{3}> mach cpu 1
using CPU 1
db{3}> bt
iic_smbus_intr_thread() at netbsd:iic_smbus_intr_thread+0x18

db{3}> mach cpu 2
using CPU 2
db{3}> bt
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193
Bad frame pointer: 0xffff8000d0a80000

db{3}> mach cpu 3
using CPU 3
db{3}> bt
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x2ba
kern_assert() at netbsd:kern_assert+0x2d
ubc_fault() at netbsd:ubc_fault+0x4c9
uvm_fault_internal() at netbsd:uvm_fault_internal+0x469
trap() at netbsd:trap+0x702
--- trap (number 0) ---
0:

db{3}> mach cpu 4
using CPU 4
db{3}> bt
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193
Bad frame pointer: 0xffff8000d0a86000

db{3}> mach cpu 5
using CPU 5
db{3}> bt
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193
Bad frame pointer: 0xffff8000d0a89800

db{3}> mach cpu 6
using CPU 6
db{3}> bt
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193
Bad frame pointer: 0xffff8000d0a8b000

db{3}> mach cpu 7
using CPU 7
db{3}> bt
x86_stihlt() at netbsd:x86_stihlt+0x6
idle_loop() at netbsd:idle_loop+0x193
Bad frame pointer: 0xffff8000d0a8f800

-- 
Nicolas Joly

Biological Software and Databanks.
Institut Pasteur, Paris.