Re: [patch 4/6] x86/smp: Cure kexec() vs. mwait_play_dead() breakage

From: Ashok Raj
Date: Sat Jun 03 2023 - 23:28:14 EST


On Sat, Jun 03, 2023 at 10:07:01PM +0200, Thomas Gleixner wrote:

[snip]

> Fixes: ea53069231f9 ("x86, hotplug: Use mwait to offline a processor, fix the legacy case")
> Reported-by: Ashok Raj <ashok.raj@xxxxxxxxx>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> ---
> arch/x86/include/asm/smp.h | 2 +
> arch/x86/kernel/smp.c | 21 +++++++---------
> arch/x86/kernel/smpboot.c | 59 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 71 insertions(+), 11 deletions(-)
>
> --- a/arch/x86/include/asm/smp.h
> +++ b/arch/x86/include/asm/smp.h
> @@ -132,6 +132,8 @@ void wbinvd_on_cpu(int cpu);
> int wbinvd_on_all_cpus(void);
> void cond_wakeup_cpu0(void);
>
> +void smp_kick_mwait_play_dead(void);
> +

This seems like its missing prototype for #else for !CONFIG_SMP

#else /* !CONFIG_SMP */
+#define smp_kick_mwait_play_dead(void) { }

Sorry I missed noticing this