Re: LOR with filedesc structure and Giant

On Fri, Aug 08, 2003 at 11:11:12PM -0700, Kris Kennaway wrote:
> Aug  9 11:29:50 dosirak kernel: lock order reversal
> Aug  9 11:29:50 dosirak kernel: 1st 0xcf3fa334 filedesc structure (filedesc structure) _at_ kern/sys_generic.c:895
> Aug  9 11:29:50 dosirak kernel: 2nd 0xc070a8e0 Giant (Giant) _at_ fs/specfs/spec_vnops.c:372
> Aug  9 11:29:50 dosirak kernel: Stack backtrace:
> 
> And that's it (i.e. no backtrace is recorded).

I got this on another machine:

lock order reversal
 1st 0xc3d25134 filedesc structure (filedesc structure) _at_ /a/asami/portbuild/i386/src-client/sys/kern/sys_generic.c:902
 2nd 0xc04aa500 Giant (Giant) _at_ /a/asami/portbuild/i386/src-client/sys/fs/specfs/spec_vnops.c:372
Stack backtrace:
backtrace(c043db3b,c04aa500,c043a130,c043a130,c04354a7) at backtrace+0x17
witness_lock(c04aa500,8,c04354a7,174,1be) at witness_lock+0x672
_mtx_lock_flags(c04aa500,0,c04354a7,174,c043e146) at _mtx_lock_flags+0xba
spec_poll(ce655af8,ce655b18,c02d152c,ce655af8,c0493d80) at spec_poll+0x134
spec_vnoperate(ce655af8,c0493d80,c35485b4,40,c42f6800) at spec_vnoperate+0x18
vn_poll(c26abe58,40,c42f6800,c3087720,c42f6800) at vn_poll+0x3c
selscan(c3087720,ce655b98,ce655b88,6,4) at selscan+0x13e
kern_select(c3087720,6,bfbff5b0,0,0) at kern_select+0x36f
select(c3087720,ce655d10,c0455f34,3ee,5) at select+0x66
syscall(2f,2f,2f,8055050,bfbff5a8) at syscall+0x273
Xint0x80_syscall() at Xint0x80_syscall+0x1d

Kris