Re: locking error using today's sources

[Andrew Doran <ad%netbsd.org@localhost>]

Hi,

I looked into this, it's quite an old bug and you were unlucky to run into
it, there's a very small window of opportunity for it to occur.  I'll see
about fixing it.

Thanks,
Andrew

On Thu, Mar 19, 2020 at 02:51:05PM -0700, David Hopper wrote:
> I just got this using today's kernel+userland during a pkgsrc Rust compilation while updating Firefox (pkgsrc also today's). ?System is a ThinkPad P53, i9 9880H and 48GB RAM:
> 
> [ 8734.5350365] panic: kernel diagnostic assertion "l->l_refcnt != 0" failed: file "/usr/src/sys/kern/kern_lwp.c", line 1701
> [ 8734.5350365] cpu2: begin traceback...
> [ 8734.5350365] vpanic() at netbsd:vpanic+0x178
> [ 8734.5350365] kern_assert() at netbsd:kern_assert+0x48
> [ 8734.5350365] lwp_addref() at netbsd:lwp_addref+0xbc
> [ 8734.5350365] procfs_rw() at netbsd:procfs_rw+0xeb
> [ 8734.5350365] VOP_READ() at netbsd:VOP_READ+0x53
> [ 8734.5350365] vn_read() at netbsd:vn_read+0x88
> [ 8734.5350365] dofileread() at netbsd:dofileread+0x8c
> [ 8734.5350365] sys_read() at netbsd:sys_read+0x49
> [ 8734.5350365] syscall() at netbsd:syscall+0x299
> [ 8734.5350365] --- syscall (number 3) ---
> [ 8734.5350365] 7519d7a42baa:
> [ 8734.5350365] cpu2: End traceback...
> [ 8734.5350365] Mutex error: mutex_vector_enter,542: locking against myself
> [ 8734.5350365] lock address : 0xffffced93d804b00
> [ 8734.5350365] current cpu ?: ? ? ? ? ? ? ? ? ?2
> [ 8734.5350365] current lwp ?: 0xffffced7c1ce42c0
> [ 8734.5350365] owner field ?: 0xffffced7c1ce42c0 wait/spin: ? ? ? ? ? ? ? ?0/0
> [ 8734.5350365] Skipping crash dump on recursive panic
> [ 8734.5350365] panic: lock error: Mutex: mutex_vector_enter,542: locking against myself: lock 0xffffced93d804b00 cpu 2 lwp 0xffffced7c1ce42c0
> [ 8734.5350365] cpu2: Begin traceback...
> [ 8734.5350365] vpanic() at netbsd:vpanic+0x178
> [ 8734.5350365] snprintf() at netbsd:snprintf
> [ 8734.5350620] lockdebug_abort() at netbsd:lockdebug_abort+0xe6
> [ 8734.5350620] mutex_vector_enter() at netbsd:mutex_vector_enter+0x3c1
> [ 8734.5350620] suspendsched() at netbsd:suspendsched+0xf5
> [ 8734.5350620] cpu_reboot() at netbsd:cpu_reboot+0x46
> [ 8734.5350620] sys_reboot() at netbsd:sys_reboot
> [ 8734.5350620] vpanic() at netbsd:vpanic+0x181
> [ 8734.5350620] kern_assert() at netbsd:kern_assert+0x48
> [ 8734.5350620] lwp_addref() at netbsd:lwp_addref+0xbc
> [ 8734.5350620] procfs_rw() at netbsd:procfs_rw+0xeb
> [ 8734.5350620] VOP_READ() at netbsd:VOP_READ+0x53
> [ 8734.5350620] vn_read() at netbsd:vn_read+0x88
> [ 8734.5350620] dofileread() at netbsd:dofileread+0x8c
> [ 8734.5350620] sys_read() at netbsd:sys_read+0x49
> [ 8734.5350620] syscall() at netbsd:syscall+0x299
> [ 8734.5350620] --- syscall (number 3) ---
> [ 8734.5350620] 7519d7a42baa:
> [ 8734.5350620] cpu2: End traceback...
> 
> Let me know if there's anything else needed.
> David
> 
> 
> 
>