From: Andi Kleen <ak@linux.intel.com>
To: Waiman Long <longman@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>,
Jonathan Corbet <corbet@lwn.net>,
x86@kernel.org, linux-kernel@vger.kernel.org,
linux-doc@vger.kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
David Woodhouse <dwmw@amazon.co.uk>,
Jiri Kosina <jikos@kernel.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Tim Chen <tim.c.chen@linux.intel.com>,
KarimAllah Ahmed <karahmed@amazon.de>,
Peter Zijlstra <peterz@infradead.org>,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [RFC PATCH] x86/speculation: Don't inherit TIF_SSBD on execve()
Date: Wed, 19 Dec 2018 16:58:41 -0800 [thread overview]
Message-ID: <20181220005841.GW25620@tassilo.jf.intel.com> (raw)
In-Reply-To: <f2cd45e2-e390-a6f6-f4fb-1d316be0f54c@redhat.com>
> You can always force disable SSB. In that case, all the child processes
> will have SSBD on.
Okay that sounds reasonable, given the below. Thanks.
-Andi
>
> >
> > Do you have a real use case where this behavior is a problem?
> >
> > -Andi
>
> Yes, we have an enterprise application partner that found that their
> application slow down up to 10-20% depending on how their application
> was set up. With the slow setup, the application was spawned by Java
> processes causing the SSBD bit to stay on when the application was running.
next prev parent reply other threads:[~2018-12-20 0:58 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-19 19:09 [RFC PATCH] x86/speculation: Don't inherit TIF_SSBD on execve() Waiman Long
2018-12-19 19:38 ` Andi Kleen
2018-12-19 19:45 ` Waiman Long
2018-12-20 0:58 ` Andi Kleen [this message]
2019-01-07 14:49 ` Waiman Long
2019-01-11 19:52 ` Thomas Gleixner
2019-01-14 21:46 ` Waiman Long
2019-01-15 9:48 ` Thomas Gleixner
2019-01-15 15:54 ` Waiman Long
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