linux-kernel - Re: Do the x86 kernel entry points need an xabort on TSX cpus?

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, 10 Feb 2012 09:24:01 -0800
From:	Andy Lutomirski <luto@...capital.net>
To:	"H. Peter Anvin" <hpa@...ux.intel.com>
Cc:	x86@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: Do the x86 kernel entry points need an xabort on TSX cpus?

On Fri, Feb 10, 2012 at 9:18 AM, H. Peter Anvin <hpa@...ux.intel.com> wrote:
> On 02/09/2012 11:40 PM, Andy Lutomirski wrote:
>>
>> [...]
>>
>>  - Ring transitions: SYSENTER, SYSCALL, SYSEXIT, and SYSRET.
>>
>> I suspect that many bits of the kernel expect that things they do
>> won't unhappen.  For example, it could be fun to do:
>>
>
> That's why entering the kernel will cause an abort.  In other words, you
> will ALWAYS abort when you do a read(), and you will never reach your
> _xabort().

Is that architecturally guaranteed?  (My manual suggests that it's
specifically *not* guaranteed, which is surprising.)

--Andy
--
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/