lock order reversal

[Duane Whitty]

Duane Whitty wrote:
>> Submitter-Id:	current-users
>> Originator:	Duane Whitty
>> Organization:	
>> Confidential:	no 
>> Synopsis:	lock order reversal
>> Severity:	serious
>> Priority:	medium
>> Category:	kern
>> Class:		sw-bug
>> Release:	FreeBSD 6.2-PRERELEASE i386
>> Environment:
> System: FreeBSD dwpc.dwlabs.ca 6.2-PRERELEASE FreeBSD 6.2-PRERELEASE #1: Tue Sep 12 00:24:56 ADT 2006 duane at dwpc.dwlabs.ca:/usr/obj/usr/src/sys/DWPC-KERNEL i386
> 
> Kernel configration

[snip]

> 	
>> Description:
> 
> lock order reversal:
>  1st 0xc06c6a40 cdev (cdev) @ /usr/src/sys/kern/kern_conf.c:61
>  2nd 0xc3281718 sleep mtxpool (sleep mtxpool) @ /usr/src/sys/kern/kern_prot.c:1877
> KDB: stack backtrace:
> kdb_backtrace(0,ffffffff,c06d77c8,c06d6f58,c06a1b04,...) at kdb_backtrace+0x29
> witness_checkorder(c3281718,9,c0668211,755) at witness_checkorder+0x578
> _mtx_lock_flags(c3281718,0,c0668211,755,c4c32700,...) at _mtx_lock_flags+0x78
> crhold(c4a4ca00,deaf593e,deaf58b0,deaf5bf4,deaf5828,...) at crhold+0x1b
> make_dev_credv(c06a79c0,0,c4a4ca00,0,0,...) at make_dev_credv+0xc6
> make_dev_cred(c06a79c0,0,c4a4ca00,0,0,...) at make_dev_cred+0x21
> pty_clone(0,c4a4ca00,deaf593e,5,deaf58b0,c329638c,0,c0660f31,212) at pty_clone+0xee
> devfs_lookupx(deaf59d0,c349ce10,c0660f31,23f,c069a300,...) at devfs_lookupx+0x2bc
> devfs_lookup(deaf59d0) at devfs_lookup+0x2d
> VOP_LOOKUP_APV(c069a300,deaf59d0) at VOP_LOOKUP_APV+0x87
> lookup(deaf5bcc) at lookup+0x47a
> namei(deaf5bcc) at namei+0x376
> vn_open_cred(deaf5bcc,deaf5ccc,0,c4a4ca00,c,...) at vn_open_cred+0x2a0
> vn_open(deaf5bcc,deaf5ccc,0,c) at vn_open+0x1e
> kern_open(c55b1190,8197850,0,3,0,...) at kern_open+0xb6
> open(c55b1190,deaf5d04) at open+0x1a
> syscall(805003b,810003b,bfbf003b,805c000,0,...) at syscall+0x22f
> Xint0x80_syscall() at Xint0x80_syscall+0x1f
> --- syscall (5, FreeBSD ELF32, open), eip = 0x2940c4f3, esp = 0xbfbfd3cc, ebp = 0xbfbfd3f8 ---
> 
>> How-To-Repeat: Unknown
>> Fix:
>
This seems to only happen after I start X11

Best Regards,

Duane Whitty