The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 74899d92e66663dc7671a8017b3146dcd4735f3b Mon Sep 17 00:00:00 2001 From: Juergen Gross <jgross@xxxxxxxx> Date: Thu, 21 Jun 2018 10:43:31 +0200 Subject: [PATCH] x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths Commit: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD") ... added speculative_store_bypass_ht_init() to the per-CPU initialization sequence. speculative_store_bypass_ht_init() needs to be called on each CPU for PV guests, too. Reported-by: Brian Woods <brian.woods@xxxxxxx> Tested-by: Brian Woods <brian.woods@xxxxxxx> Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: boris.ostrovsky@xxxxxxxxxx Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx Fixes: 1f50ddb4f4189243c05926b842dc1a0332195f31 ("x86/speculation: Handle HT correctly on AMD") Link: https://lore.kernel.org/lkml/20180621084331.21228-1-jgross@xxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c index 2e20ae2fa2d6..e3b18ad49889 100644 --- a/arch/x86/xen/smp_pv.c +++ b/arch/x86/xen/smp_pv.c @@ -32,6 +32,7 @@ #include <xen/interface/vcpu.h> #include <xen/interface/xenpmu.h> +#include <asm/spec-ctrl.h> #include <asm/xen/interface.h> #include <asm/xen/hypercall.h> @@ -70,6 +71,8 @@ static void cpu_bringup(void) cpu_data(cpu).x86_max_cores = 1; set_cpu_sibling_map(cpu); + speculative_store_bypass_ht_init(); + xen_setup_cpu_clockevents(); notify_cpu_starting(cpu); @@ -250,6 +253,8 @@ static void __init xen_pv_smp_prepare_cpus(unsigned int max_cpus) } set_cpu_sibling_map(0); + speculative_store_bypass_ht_init(); + xen_pmu_init(0); if (xen_smp_intr_init(0) || xen_smp_intr_init_pv(0))