Re: kern/41261: Crash with nullfs

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

On Tue, Apr 21, 2009 at 07:45:00PM +0000, joerg%NetBSD.org@localhost wrote:

> fatal breakpoint trap in supervisor mode
> trap type 1 code 0 rip ffffffff80518b75 cs 8 rflags 246 cr2  7f7ffd96cf00 cpl 
> Stopped in pid 778.1 (mount_null) at    netbsd:breakpoint+0x5:  leave
> db{3}> bt
> breakpoint() at netbsd:breakpoint+0x5
> cpu_Debugger() at netbsd:cpu_Debugger+0x9
> panic() at netbsd:panic+0x24d
> __kernassert() at netbsd:__kernassert+0x2d
> uvm_pagealloc_strat() at netbsd:uvm_pagealloc_strat+0x549
> pmap_growkernel() at netbsd:pmap_growkernel+0x322
> uvm_map_prepare() at netbsd:uvm_map_prepare+0x230
> uvm_map() at netbsd:uvm_map+0xd0
> uvm_km_alloc() at netbsd:uvm_km_alloc+0xa8
> kmem_backend_alloc() at netbsd:kmem_backend_alloc+0x76
> vmem_xalloc() at netbsd:vmem_xalloc+0x3fc
> vmem_alloc() at netbsd:vmem_alloc+0xf2
> kmem_alloc() at netbsd:kmem_alloc+0x3d
> hashinit() at netbsd:hashinit+0x56
> nullfs_mount() at netbsd:nullfs_mount+0x176
> VFS_MOUNT() at netbsd:VFS_MOUNT+0x44
> do_sys_mount() at netbsd:do_sys_mount+0x625
> sys___mount50() at netbsd:sys___mount50+0x33
> syscall() at netbsd:syscall+0xb6

ptp_va2o() can return duplicate offsets for the same uvm_object?
Or there is a bug in its use? I'd be somewhat surprised.