From: Willy Tarreau <w@1wt.eu>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de,
gnomes@lxorguk.ukuu.org.uk, torvalds@linux-foundation.org
Subject: Re: [PATCH RFC 2/4] x86/arch_prctl: add ARCH_GET_NOPTI and ARCH_SET_NOPTI to enable/disable PTI
Date: Mon, 8 Jan 2018 17:56:51 +0100 [thread overview]
Message-ID: <20180108165651.GC10913@1wt.eu> (raw)
In-Reply-To: <20180108164900.GO32035@hirez.programming.kicks-ass.net>
On Mon, Jan 08, 2018 at 05:49:00PM +0100, Peter Zijlstra wrote:
> On Mon, Jan 08, 2018 at 05:12:17PM +0100, Willy Tarreau wrote:
> > + if (doit) {
> > + if (arg2)
> > + task_thread_info(task)->flags |= _TIF_NOPTI;
> > + else
> > + task_thread_info(task)->flags &= ~_TIF_NOPTI;
>
> {set,clear}_thread_flag() please, the above is not SMP safe.
Oops, thank you. I initially thought about it initially but didn't
know the names of the functions to use, and have left it there
thinking I'd fix it later. Usual source of bugs :-/
Bah and I left my debugging printk() in the patch as well! I'll
rework this a bit.
Thanks,
Willy
next prev parent reply other threads:[~2018-01-08 16:57 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-08 16:12 [PATCH RFC 0/4] Per-task PTI activation Willy Tarreau
2018-01-08 16:12 ` [PATCH RFC 1/4] x86/thread_info: add TIF_NOPTI to disable PTI per task Willy Tarreau
2018-01-08 16:57 ` Thomas Gleixner
2018-01-08 17:03 ` Willy Tarreau
2018-01-08 17:14 ` Ingo Molnar
2018-01-08 16:12 ` [PATCH RFC 2/4] x86/arch_prctl: add ARCH_GET_NOPTI and ARCH_SET_NOPTI to enable/disable PTI Willy Tarreau
2018-01-08 16:49 ` Peter Zijlstra
2018-01-08 16:56 ` Willy Tarreau [this message]
2018-01-08 17:02 ` Thomas Gleixner
2018-01-08 17:10 ` Willy Tarreau
2018-01-08 17:17 ` Ingo Molnar
2018-01-08 17:26 ` Thomas Gleixner
2018-01-08 17:46 ` Ingo Molnar
2018-01-08 17:05 ` Ingo Molnar
2018-01-08 17:19 ` Peter Zijlstra
2018-01-08 17:26 ` Ingo Molnar
2018-01-08 17:50 ` Borislav Petkov
2018-01-08 17:54 ` Linus Torvalds
2018-01-08 18:22 ` Willy Tarreau
2018-01-08 20:49 ` Thomas Gleixner
2018-01-08 21:03 ` Willy Tarreau
2018-01-08 20:35 ` Willy Tarreau
2018-01-08 16:12 ` [PATCH RFC 3/4] x86/pti: don't mark the user PGD with _PAGE_NX Willy Tarreau
2018-01-08 17:03 ` Dave Hansen
2018-01-08 17:17 ` Willy Tarreau
2018-01-08 17:23 ` Dave Hansen
2018-01-08 17:30 ` Peter Zijlstra
2018-01-08 17:49 ` Willy Tarreau
2018-01-08 17:21 ` Ingo Molnar
2018-01-08 23:05 ` Andy Lutomirski
2018-01-08 23:09 ` Kees Cook
2018-01-09 4:22 ` Willy Tarreau
2018-01-08 17:05 ` Thomas Gleixner
2018-01-08 17:28 ` Dave Hansen
2018-01-08 17:50 ` Ingo Molnar
2018-01-08 18:25 ` Alan Cox
2018-01-08 18:35 ` Ingo Molnar
2018-01-08 18:35 ` Linus Torvalds
2018-01-08 18:44 ` Dave Hansen
2018-01-08 16:12 ` [PATCH RFC 4/4] x86/entry/pti: don't switch PGD on tasks holding flag TIF_NOPTI Willy Tarreau
2018-01-08 17:11 ` Ingo Molnar
2018-01-08 17:20 ` Dave Hansen
2018-01-08 18:12 ` Willy Tarreau
2018-01-08 23:01 ` Andy Lutomirski
2018-01-08 16:59 ` [PATCH RFC 0/4] Per-task PTI activation Dave Hansen
2018-01-08 17:06 ` Willy Tarreau
2018-01-08 17:17 ` Dave Hansen
2018-01-08 17:13 ` Ingo Molnar
2018-01-09 15:31 ` Eric W. Biederman
2018-01-09 16:02 ` Willy Tarreau
2018-01-09 18:11 ` Zhi Wang
2018-01-09 21:07 ` Eric W. Biederman
2018-01-09 21:57 ` Willy Tarreau
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