Re: Crash on -current amd64

[Paul Goyette <paul%whooppee.com@localhost>]

On Mon, 4 Jul 2016, Martin Husemann wrote:

> On Mon, Jul 04, 2016 at 09:53:21AM +0800, Paul Goyette wrote:
> > vapnic + 0x140
> > cd_play_msf +0x0
> > kauth_cred_geteuid + 0x50
>
> There is something wrong here: kauth_cred_geteuid can't ever call 
> cd_play_msf.

Well, it's also unlikely for the return address of vpanic to point to 
the _beginning_ of any routine - you would (always?) have to have had to 
execute the routine prologue at a minimum.  :)

The value of cd_play_msf is 0xffffffff8044c675, which corresponds 
exactly to the end of .text segment (and start of .text.unlikely).
The very last object module in the .text segment is libkern.o, and the 
very last symbol there is kassert, at address 0xffffffff8044c62d.

So, cd_play_msf the same as the last+1 byte of kassert.  :)


+------------------+--------------------------+------------------------+
| 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 |
+------------------+--------------------------+------------------------+