linux-kernel - Re: [PATCH 3/4] x86/asm: Add asm macros for static keys/jump labels

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: <CALCETrXTyio8gh0w=sn8JQx4NArWoVhOLNz2yVN=jKxvR8w7wg@mail.gmail.com>
Date:	Sun, 8 Nov 2015 08:16:11 -0800
From:	Andy Lutomirski <luto@...capital.net>
To:	Thomas Gleixner <tglx@...utronix.de>
Cc:	Borislav Petkov <bp@...en8.de>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Brian Gerst <brgerst@...il.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	X86 ML <x86@...nel.org>, Peter Zijlstra <peterz@...radead.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH 3/4] x86/asm: Add asm macros for static keys/jump labels

On Sat, Nov 7, 2015 at 9:08 AM, Thomas Gleixner <tglx@...utronix.de> wrote:
> On Sat, 7 Nov 2015, Andy Lutomirski wrote:
>> On Sat, Nov 7, 2015 at 8:58 AM, Thomas Gleixner <tglx@...utronix.de> wrote:
>> True.  But I hid it in a header file, too, but it was just a different
>> header file -- I had it all hidden away as CALL_ENTER_FROM_USER_MODE.
>
> It probably does not really make a difference :)
>
> I just got triggered by you saying:
>
>> Unfortunately, these only work if HAVE_JUMP_LABEL ....
>

Looking again, my patch is crappy is one obvious respect: on
non-HAVE_JUMP_LABEL kernels, I'm still generating a macro that will
compile but do the wrong thing.  I'll add better comments and the
correct ifdef in v2.  That will make it much harder to screw up
without causing a compiler error.

--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/