linux-kernel - Re: Issues with "x86, um: switch to generic fork/vfork/clone" commit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 9 Nov 2012 21:47:54 -0800
From:	Michel Lespinasse <walken@...gle.com>
To:	Al Viro <viro@...iv.linux.org.uk>
Cc:	linux-next@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>,
	Hugh Dickins <hughd@...gle.com>
Subject: Re: Issues with "x86, um: switch to generic fork/vfork/clone" commit

On Fri, Nov 9, 2012 at 9:33 PM, Al Viro <viro@...iv.linux.org.uk> wrote:
> On Fri, Nov 09, 2012 at 08:57:58PM -0800, Michel Lespinasse wrote:
>> On Fri, Nov 9, 2012 at 8:51 PM, Al Viro <viro@...iv.linux.org.uk> wrote:
>> > On Fri, Nov 09, 2012 at 08:36:53PM -0800, Michel Lespinasse wrote:
>> >> Hi,
>> >>
>> >> I'm having an issue booting current linux-next kernels on my test
>> >> machines. Userspace crashes when it's supposed to pivot to the rootfs.
>> >> With the loglevel=8 kernel parameter, the last messages I see are:
>> >>
>> >> Checking root filesystem in pivot_root init.
>> >> [    6.252717] usb 2-1: link qh256-0001/ffff880853ec9ab8 start 1 [1/0 us]
>> >> [    6.259419] hub 2-1:1.0: state 7 ports 8 chg 0000 evt 0000
>> >> [    6.292302] traps: hotplug[1633] general protection ip:f767c06b
>> >> sp:ffbb2d1c error:0 in libc-2.3.6.so[f7652000+126000]
>> >>
>> >> I ran a bisection and it turns out that
>> >> e52d03a3775841cc68d0ea9d86f2f09b603c41e6 (x86, um: switch to generic
>> >> fork/vfork/clone) is the commit breaking my setup. When reverting
>> >> that, I am able to boot linux-next (or mmotm, which is what I was
>> >> trying to do in the first place) without issues.
>> >>
>> >> Sorry for not having a more complete root cause at the moment - I'm
>> >> lacking some context as to what the change is trying to do.
>> >
>> > Hmm...  32bit native, presumably?
>>
>> This is running on a x86_64 system; I believe the userspace binaries
>> should be 64-bit as well.
>
> Curious...  After the second look at that sucker, it seems that you have
> 32bit hotplug(8) in there, and yes, it's clearly a 64bit kernel...  Could
> you check which binary it is and whether it's really 32bit or not?

Looks like /sbin/hotplug is a script on this system, using /bin/bash
as the interpreter, and /bin/bash is ELF 32-bit LSB executable.
(wow, I had no idea, I thought more of that system was 64-bits :)

-- 
Michel "Walken" Lespinasse
A program is never fully debugged until the last user dies.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/