From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Steven Rostedt <rostedt@goodmis.org>,
"security@kernel.org" <security@kernel.org>,
X86 ML <x86@kernel.org>, Sasha Levin <sasha.levin@oracle.com>,
linux-kernel@vger.kernel.org,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Andrew Cooper <andrew.cooper3@citrix.com>,
Jan Beulich <jbeulich@suse.com>,
xen-devel <xen-devel@lists.xen.org>,
stable@vger.kernel.org
Subject: Re: [PATCH v4 1/3] x86/ldt: Make modify_ldt synchronous
Date: Sat, 25 Jul 2015 11:03:40 +0200 [thread overview]
Message-ID: <20150725090340.GD3427@nazgul.tnic> (raw)
In-Reply-To: <12ddcec938d76238975dff9de7d66cfc6e574aa7.1437802102.git.luto@kernel.org>
On Fri, Jul 24, 2015 at 10:36:44PM -0700, Andy Lutomirski wrote:
> modify_ldt has questionable locking and does not synchronize
> threads. Improve it: redesign the locking and synchronize all
> threads' LDTs using an IPI on all modifications.
>
> This will dramatically slow down modify_ldt in multithreaded
> programs, but there shouldn't be any multithreaded programs that
> care about modify_ldt's performance in the first place.
>
> Cc: stable@vger.kernel.org
> Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
--
next prev parent reply other threads:[~2015-07-25 9:03 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-25 5:36 [PATCH v4 0/3] x86: modify_ldt improvement, test, and config option Andy Lutomirski
2015-07-25 5:36 ` [PATCH v4 1/3] x86/ldt: Make modify_ldt synchronous Andy Lutomirski
2015-07-25 9:03 ` Borislav Petkov [this message]
2015-07-25 5:36 ` [PATCH v4 2/3] x86/ldt: Make modify_ldt optional Andy Lutomirski
2015-07-25 6:23 ` Willy Tarreau
2015-07-25 6:44 ` Andy Lutomirski
2015-07-25 7:50 ` Willy Tarreau
2015-07-25 13:03 ` [PATCH 4/3] x86/ldt: allow to disable modify_ldt at runtime Willy Tarreau
2015-07-25 16:08 ` Andy Lutomirski
2015-07-25 16:33 ` Willy Tarreau
2015-07-25 17:42 ` Andy Lutomirski
2015-07-25 18:45 ` Willy Tarreau
2015-07-27 19:04 ` Kees Cook
2015-07-27 21:37 ` Willy Tarreau
2015-07-25 9:15 ` [PATCH v4 2/3] x86/ldt: Make modify_ldt optional Borislav Petkov
2015-07-25 16:03 ` Andy Lutomirski
2015-07-25 16:35 ` Willy Tarreau
2015-07-25 5:36 ` [PATCH v4 3/3] selftests/x86, x86/ldt: Add a selftest for modify_ldt Andy Lutomirski
2015-07-27 15:52 ` [PATCH v4.1 3.3] " Andy Lutomirski
2015-07-25 6:27 ` [PATCH v4 0/3] x86: modify_ldt improvement, test, and config option Willy Tarreau
2015-07-27 15:36 ` Boris Ostrovsky
2015-07-27 15:53 ` Andy Lutomirski
2015-07-27 16:18 ` Boris Ostrovsky
2015-07-28 2:20 ` Andy Lutomirski
2015-07-28 3:16 ` Andy Lutomirski
2015-07-28 3:23 ` Andy Lutomirski
2015-07-28 3:43 ` Boris Ostrovsky
2015-07-28 10:29 ` Andrew Cooper
2015-07-28 14:05 ` Boris Ostrovsky
2015-07-28 14:35 ` Andrew Cooper
2015-07-28 14:50 ` Boris Ostrovsky
2015-07-28 15:15 ` Konrad Rzeszutek Wilk
2015-07-28 15:39 ` Boris Ostrovsky
2015-07-28 15:23 ` Andrew Cooper
2015-07-28 15:59 ` [Xen-devel] " Boris Ostrovsky
2015-07-28 15:43 ` Andy Lutomirski
2015-07-28 16:30 ` Andrew Cooper
2015-07-28 17:07 ` Andy Lutomirski
2015-07-28 17:10 ` [Xen-devel] " Boris Ostrovsky
2015-07-29 0:21 ` Andy Lutomirski
2015-07-29 0:47 ` Andrew Cooper
2015-07-29 3:01 ` Boris Ostrovsky
2015-07-29 4:26 ` Andy Lutomirski
2015-07-29 5:28 ` Andy Lutomirski
2015-07-29 14:21 ` Andrew Cooper
2015-07-29 14:43 ` Boris Ostrovsky
2015-07-29 19:03 ` Andrew Cooper
2015-07-29 21:23 ` Boris Ostrovsky
2015-07-29 21:26 ` Andy Lutomirski
2015-07-29 21:33 ` Boris Ostrovsky
2015-07-29 21:37 ` Andrew Cooper
2015-07-29 22:05 ` Andy Lutomirski
2015-07-29 22:11 ` Andrew Cooper
2015-07-29 22:40 ` Boris Ostrovsky
2015-07-29 22:46 ` David Vrabel
2015-07-29 22:49 ` Boris Ostrovsky
2015-07-29 22:55 ` David Vrabel
2015-07-29 23:02 ` Andrew Cooper
2015-07-29 23:13 ` Andy Lutomirski
2015-07-30 0:29 ` Andrew Cooper
2015-07-30 18:30 ` Andy Lutomirski
2015-07-30 18:54 ` Andrew Cooper
2015-07-30 20:01 ` Boris Ostrovsky
2015-07-30 20:05 ` Andy Lutomirski
2015-07-30 20:18 ` Boris Ostrovsky
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