Re: port-amd64/58366: KASLR broken

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

The following reply was made to PR port-amd64/58366; it has been noted by GNATS.

From: Taylor R Campbell <riastradh%NetBSD.org@localhost>
To: Harold Gutch <logix%foobar.franken.de@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, port-amd64-maintainer%NetBSD.org@localhost,
	gnats-admin%NetBSD.org@localhost, netbsd-bugs%NetBSD.org@localhost
Subject: Re: port-amd64/58366: KASLR broken
Date: Thu, 27 Jun 2024 23:15:40 +0000

 > Date: Thu, 27 Jun 2024 20:36:34 +0200
 > From: Harold Gutch <logix%foobar.franken.de@localhost>
 > 
 > On Tue, Jun 25, 2024 at 06:05:01PM +0000, Taylor R Campbell wrote:
 > >  Can you try the patch on top of the first revision you found with
 > >  broken prekern?
 > >  
 > >  If that works, time for another round of bisection, I guess!
 > 
 > I am not 100% sure, but it might be
 > https://mail-index.netbsd.org/source-changes/2024/03/25/msg150542.html
 > , however I don't see where aes_sse2_selftest() or 
 > aes_sse2_xts_update_selftest() might be calling snprintb().
 > 
 > There might also be some undefined behavior involved somewhere as not
 > every boot panics - it's hard to say how often it happens, but I'd put
 > it at around p=50%.  With a source tree from just before that change I
 > have so far not encountered this panic a single time.
 > 
 > So, I'd say your patch has improved things but the snprintb() issue
 > also needs to be addressed.
 
 Bizarre!
 
 Can you:
 
 1. update to the snprintb change,
 2. apply the pmap directmap patch I attached earlier,
 3. put db_stacktrace() (#include <ddb/ddb.h>) at the top of snprintb_m,
 and
 4. share dmesg when it panics?