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Date:   Wed, 19 Dec 2018 16:58:41 -0800
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>,
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Subject: Re: [RFC PATCH] x86/speculation: Don't inherit TIF_SSBD on execve()
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> 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.