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Date:   Mon, 9 May 2022 11:55:35 +0200
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Sven Schnelle <svens@linux.ibm.com>,
        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()
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On Mon, May 09, 2022 at 09:08:31AM +0200, Peter Zijlstra wrote:
> 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!

Merged into commit message, and applied both patches to s390 tree.

Thanks!