2018-06-21 08:44:38

by Jürgen Groß

[permalink] [raw]
Subject: [PATCH] x86/xen: add call of speculative_store_bypass_ht_init() to pv paths

Commit 1f50ddb4f4189243c05926b842dc1a0332195f31 ("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 <[email protected]>
Fixes: 1f50ddb4f4189243c05926b842dc1a0332195f31 ("x86/speculation: Handle HT correctly on AMD")
Cc: <[email protected]>
Signed-off-by: Juergen Gross <[email protected]>
Tested-by: Brian Woods <[email protected]>
---
arch/x86/xen/smp_pv.c | 5 +++++
1 file changed, 5 insertions(+)

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))
--
2.13.7



2018-06-21 13:04:30

by Boris Ostrovsky

[permalink] [raw]
Subject: Re: [PATCH] x86/xen: add call of speculative_store_bypass_ht_init() to pv paths

On 06/21/2018 04:43 AM, Juergen Gross wrote:
> Commit 1f50ddb4f4189243c05926b842dc1a0332195f31 ("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 <[email protected]>
> Fixes: 1f50ddb4f4189243c05926b842dc1a0332195f31 ("x86/speculation: Handle HT correctly on AMD")
> Cc: <[email protected]>
> Signed-off-by: Juergen Gross <[email protected]>
> Tested-by: Brian Woods <[email protected]>
>



Reviewed-by: Boris Ostrovsky <[email protected]>