From 6fec8fa1b57b4db88781f26bd2f084be5c4edd6a Mon Sep 17 00:00:00 2001 From: Roger Pau Monne Date: Thu, 22 May 2025 09:23:33 +0200 Subject: [PATCH] x86/traps: remove smp_mb() ahead of IPI dispatch MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The IPI dispatch functions already have the required barriers to ensure correct memory ordering. Note other callers of send_IPI_mask() don't use any barriers. No functional change intended. Reported-by: Andrew Cooper Signed-off-by: Roger Pau Monné Reviewed-by: Jan Beulich --- xen/arch/x86/traps.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c index c94779b4ad..22f2062932 100644 --- a/xen/arch/x86/traps.c +++ b/xen/arch/x86/traps.c @@ -785,8 +785,6 @@ void fatal_trap(const struct cpu_user_regs *regs, bool show_remote) cpumask_andnot(&show_state_mask, &cpu_online_map, cpumask_of(smp_processor_id())); set_nmi_callback(nmi_show_execution_state); - /* Ensure new callback is set before sending out the NMI. */ - smp_wmb(); smp_send_nmi_allbutself(); /* Wait at most 10ms for some other CPU to respond. */