Re: [PATCH 1/2] entry: Rename arch_check_user_regs() to arch_enter_from_user_mode()

Peter Zijlstra
2022-05-09T07:25:37Z

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!