kern/51265: dtrace redefines global symbol vpanic

[paul%whooppee.com@localhost]

>Number:         51265
>Category:       kern
>Synopsis:       dtrace module redefines global symbol 'vpanic'
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jun 23 01:00:01 +0000 2016
>Originator:     Paul Goyette
>Release:        NetBSD 7.99.30
>Organization:
+------------------+--------------------------+------------------------+
| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
| (Retired)        | FA29 0E3B 35AF E8AE 6651 | paul at whooppee.com   |
| Kernel Developer | 0786 F758 55DE 53BA 7731 | pgoyette at netbsd.org |
+------------------+--------------------------+------------------------+
>Environment:
	
	
System: NetBSD pokey.whooppee.com 7.99.30 NetBSD 7.99.30 (POKEY 2016-06-14 11:43:31) #0: Tue Jun 14 23:37:31 PHT 2016 paul%pokey.whooppee.com@localhost:/build/netbsd-local/obj/amd64/sys/arch/amd64/compile/POKEY amd64
Architecture: x86_64
Machine: amd64
>Description:
	In the machine-specific dev/dtrace/*/dtrace_asm.S a duplicate
	definition of vpanic() is provided.  It's not clear to me if
	this needs to override the standard system definition of
	vpanic().  However, with the recent fix of PR kern/45125 we
	now properly detect the redefinition of the global symbol, and
	fail to load the module.

	Since dtrace is available _only_ as a module, this effectively
	renders dtrace inoperative.
	
>How-To-Repeat:
	On -current, with the fix for PR kern/45125, try to load the
	dtrace module (either via a boot-loader 'load dtrace' command,
	or after boot with modload(8)).
	
>Fix:
	Unknown.

	Possibly rename the assembler routines, although there seems to
	already be a dtrace_vpanic() wrapper.
	

>Unformatted: