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Date:   Mon, 9 May 2022 09:08:31 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Sven Schnelle <svens@linux.ibm.com>
Cc:     Thomas Richter <tmricht@linux.ibm.com>,
        linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH 1/2] entry: Rename arch_check_user_regs() to
 arch_enter_from_user_mode()
Message-ID: <20220509070831.GD76023@worktop.programming.kicks-ass.net>
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 <yt9dsfpjgrba.fsf@linux.ibm.com>
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On Mon, May 09, 2022 at 08:20:41AM +0200, Sven Schnelle wrote:
> Peter Zijlstra <peterz@infradead.org> writes:
> 
> > On Wed, May 04, 2022 at 08:23:50AM +0200, Thomas Richter wrote:
> >> From: Sven Schnelle <svens@linux.ibm.com>
> >> 
> >> arch_check_user_regs() is used at the moment to verify that struct pt_regs
> >> contains valid values when entering the kernel from userspace. s390 needs
> >> a place in the generic entry code to modify a cpu data structure when
> >> switching from userspace to kernel mode. As arch_check_user_regs() is
> >> exactly this, rename it to arch_enter_from_user_mode().
> >> 
> >> Cc: Thomas Gleixner <tglx@linutronix.de>
> >> Cc: Peter Zijlstra <peterz@infradead.org>
> >> Cc: Andy Lutomirski <luto@kernel.org>
> >> Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
> >> ---
> >
> > With the note that NMI doesn't (necessarily) call this..
> >
> > Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> 
> How about:
> 
> "When entering the kernel from userspace, arch_check_user_regs() is
>  used to verify that struct pt_regs contains valid values. Note that
>  the NMI codepath doesn't call this function. s390 needs a place in the
>  generic entry code to modify a cpu data structure when switching from
>  userspace to kernel mode. As arch_check_user_regs() is exactly this,
>  rename it to arch_enter_from_user_mode()."

Sure, thanks!