Patches to get Arla running on FreeBSD 8-CURRENT

[Robert Watson]

On Fri, 22 Feb 2008, Alec Kloss wrote:

> Robert, I've been playing with your patches, etc. on 8-CURRENT. I've been 
> having to tweak up include/config.h a little so I wonder if you missed a few 
> autoconf things... but more important, running "ls /afs" results in:

This is a symptom of a failure to insmntque a vnode after creating it, a new 
requirement for vnodes in FreeBSD 7.x/8.x; previously, vnodes were 
automatically inserted on the mount vnode queue and had their mount pointer 
set up during getnewvnode(), but closing certain races motivated this change. 
The reason I know this is that I remember adding two calls to insmntque to 
nnpfs in my patches, so there are three possibilities: (1) I missed a call to 
getnewvnode, (2) the patches I posted didn't include that change, or (3) the 
patch didn't apply properly.  I'll investigate this later today once I've 
given my FOSDEM talk; chances are it's an issue with the patch.

Robert N M Watson
Computer Laboratory
University of Cambridge


>
> nnpfs: cdev: 0, syscall: 339
>
>
> Fatal trap 12: page fault while in kernel mode
> cpuid = 0; apic id = 00
> fault virtual address   = 0x26c
> fault code              = supervisor read, page not present
> instruction pointer     = 0x20:0xc2a7f1fc
> stack pointer           = 0x28:0xcd412a40
> frame pointer           = 0x28:0xcd412a5c
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                        = DPL 0, pres 1, def32 1, gran 1
> processor eflags        = interrupt enabled, resume, IOPL = 0
> current process         = 4822 (ls)
> [thread pid 4822 tid 100176 ]
> Stopped at      nnpfs_getattr_common+0xc:       movl
> 0x26c(%eax),%eax
> db> bt
> Tracing pid 4822 tid 100176 td 0xc2783440 nnpfs_getattr_common(c297b110,cd412ab4,c24f1700,c2783440,cd412aa0,...) at nnpfs_getattr_common+0xc
> nnpfs_getattr(cd412aa0,0,c0b10208,cd412b48,cd412b28,...) at nnpfs_getattr+0x33
> VOP_GETATTR_APV(c2a854a0,cd412aa0,c0bd91a0,c297b110,cd412ab4,...) at VOP_GETATTR_APV+0xa5
> vn_stat(c297b110,cd412b48,c24f1700,0,c2783440,...) at vn_stat+0x49
> kern_stat(c2783440,8113138,0,cd412c18,c0c5d140,...) at kern_stat+0x81
> stat(c2783440,cd412cfc,8,cd412d38,c0ba1e60,...) at stat+0x2f
> syscall(cd412d38) at syscall+0x2b3
> Xint0x80_syscall() at Xint0x80_syscall+0x20
> --- syscall (188, FreeBSD ELF32, stat), eip = 0x281a3acb, esp = 0xbfbfe54c, ebp = 0xbfbfe5d8 ---
> db>
>
> If I'me reading this (and nnpfs_vnodeops_common.c) right, this is
> probably a NULL value for (xn or perhaps vap) in
>
>        *vap = xn->attr;
>
> (line 765) Any thoughts?  Or tips on what I can do to help?  I
> don't have gdb ready to go yet---but I probably can this weekend.
>
> -- 
> Alec Kloss  alec at SetFilePointer.com   IM: angryspamhater at yahoo.com
> PGP key at http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xA241980E
> "No Bunny!" -- Simon, from Frisky Dingo
>