From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH 15/22] x86/entry: Add TIF_NEED_FPU_LOAD
Date: Thu, 14 Feb 2019 16:28:14 +0100
Message-ID: <20190214152814.dptm4edcpfn7vrff@linutronix.de>
References: <20190109114744.10936-1-bigeasy@linutronix.de>
 <20190109114744.10936-16-bigeasy@linutronix.de>
 <20190130115507.GE18383@zn.tnic>
 <20190207114941.jzydrry5xpjngyiv@linutronix.de>
 <20190213093553.GC9683@zn.tnic>
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Cc: linux-kernel@vger.kernel.org, x86@kernel.org,
        Andy Lutomirski <luto@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        kvm@vger.kernel.org, "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Rik van Riel <riel@surriel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
To: Borislav Petkov <bp@alien8.de>
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On 2019-02-13 10:35:53 [+0100], Borislav Petkov wrote:
…
> > + *
> > + * If TIF_NEED_FPU_LOAD is cleared then CPU's FPU registers are holding the
> > + * current content of current()'s FPU register state.
> 
> "current content of current" - that's a lot of c...
> 
> Make that
> 
> "... then the CPU's FPU registers are mirrored in the current thread's
> FPU registers state."

Replaced `mirrored' with saved:

+ * If TIF_NEED_FPU_LOAD is cleared then the CPU's FPU registers are saved in
+ * the current thread's FPU registers state.
+ * If TIF_NEED_FPU_LOAD is set then CPU's FPU registers may not hold current()'s
+ * FPU registers. It is required to load the registers before returning to
+ * userland or using the content otherwise.

Sebastian