linux-kernel - Re: [PATCH v3 5/5] x86/entry/64: Bypass enter_from_user

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]

Message-ID: <alpine.DEB.2.11.1511130923090.3903@nanos>
Date:	Fri, 13 Nov 2015 09:23:25 -0500 (EST)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Andy Lutomirski <luto@...nel.org>
cc:	x86@...nel.org, linux-kernel@...r.kernel.org,
	Brian Gerst <brgerst@...il.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Borislav Petkov <bp@...en8.de>,
	Frédéric Weisbecker <fweisbec@...il.com>,
	Peter Zijlstra <peterz@...radead.org>
Subject: Re: [PATCH v3 5/5] x86/entry/64: Bypass enter_from_user_mode on
 non-context-tracking boots

On Thu, 12 Nov 2015, Andy Lutomirski wrote:
> On CONFIG_CONTEXT_TRACKING kernels that have context tracking
> disabled at runtime (which includes most distro kernels), we still
> have the overhead of a call to enter_from_user_mode in interrupt and
> exception entries.
> 
> If jump labels are available, this uses the jump label
> infrastructure to skip the call.
> 
> Signed-off-by: Andy Lutomirski <luto@...nel.org>

Reviewed-by: Thomas Gleixner <tglx@...utronix.de>
--
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/