summaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/spec-ctrl.h11
-rw-r--r--arch/x86/kernel/smpboot.c12
2 files changed, 21 insertions, 2 deletions
diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h
index cb0386fc4dc3..c648502e4535 100644
--- a/arch/x86/include/asm/spec-ctrl.h
+++ b/arch/x86/include/asm/spec-ctrl.h
@@ -4,6 +4,7 @@
#include <linux/thread_info.h>
#include <asm/nospec-branch.h>
+#include <asm/msr.h>
/*
* On VMENTER we must preserve whatever view of the SPEC_CTRL MSR
@@ -76,6 +77,16 @@ static inline u64 ssbd_tif_to_amd_ls_cfg(u64 tifn)
return (tifn & _TIF_SSBD) ? x86_amd_ls_cfg_ssbd_mask : 0ULL;
}
+/*
+ * This can be used in noinstr functions & should only be called in bare
+ * metal context.
+ */
+static __always_inline void __update_spec_ctrl(u64 val)
+{
+ __this_cpu_write(x86_spec_ctrl_current, val);
+ native_wrmsrl(MSR_IA32_SPEC_CTRL, val);
+}
+
#ifdef CONFIG_SMP
extern void speculative_store_bypass_ht_init(void);
#else
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 2a187c0cbd5b..f7bcd42edaeb 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -87,6 +87,7 @@
#include <asm/hw_irq.h>
#include <asm/stackprotector.h>
#include <asm/sev.h>
+#include <asm/spec-ctrl.h>
/* representing HT siblings of each logical CPU */
DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
@@ -640,13 +641,13 @@ static void __init build_sched_topology(void)
};
#endif
/*
- * When there is NUMA topology inside the package skip the DIE domain
+ * When there is NUMA topology inside the package skip the PKG domain
* since the NUMA domains will auto-magically create the right spanning
* domains based on the SLIT.
*/
if (!x86_has_numa_in_package) {
x86_topology[i++] = (struct sched_domain_topology_level){
- cpu_cpu_mask, x86_die_flags, SD_INIT_NAME(DIE)
+ cpu_cpu_mask, x86_die_flags, SD_INIT_NAME(PKG)
};
}
@@ -1596,8 +1597,15 @@ void __noreturn hlt_play_dead(void)
native_halt();
}
+/*
+ * native_play_dead() is essentially a __noreturn function, but it can't
+ * be marked as such as the compiler may complain about it.
+ */
void native_play_dead(void)
{
+ if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS))
+ __update_spec_ctrl(0);
+
play_dead_common();
tboot_shutdown(TB_SHUTDOWN_WFS);