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authorLinus Torvalds <torvalds@linux-foundation.org>2018-07-08 22:56:25 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2018-07-08 22:56:25 +0200
commit23adbe6fb571897b57c1f3dd952d598edce2f8e6 (patch)
tree401ac64fad518180fa1257b574613e1f4b57560e /arch
parentMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/ker... (diff)
parentx86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR (diff)
downloadlinux-23adbe6fb571897b57c1f3dd952d598edce2f8e6.tar.xz
linux-23adbe6fb571897b57c1f3dd952d598edce2f8e6.zip
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/pti updates from Thomas Gleixner: "Two small fixes correcting the handling of SSB mitigations on AMD processors" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR x86/bugs: Update when to check for the LS_CFG SSBD mitigation
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/cpu/amd.c4
-rw-r--r--arch/x86/kernel/cpu/bugs.c8
2 files changed, 8 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 082d7875cef8..38915fbfae73 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -543,7 +543,9 @@ static void bsp_init_amd(struct cpuinfo_x86 *c)
nodes_per_socket = ((value >> 3) & 7) + 1;
}
- if (c->x86 >= 0x15 && c->x86 <= 0x17) {
+ if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
+ !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
+ c->x86 >= 0x15 && c->x86 <= 0x17) {
unsigned int bit;
switch (c->x86) {
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 404df26b7de8..5c0ea39311fe 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -155,7 +155,8 @@ x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest)
guestval |= guest_spec_ctrl & x86_spec_ctrl_mask;
/* SSBD controlled in MSR_SPEC_CTRL */
- if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD))
+ if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
+ static_cpu_has(X86_FEATURE_AMD_SSBD))
hostval |= ssbd_tif_to_spec_ctrl(ti->flags);
if (hostval != guestval) {
@@ -533,9 +534,10 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
* Intel uses the SPEC CTRL MSR Bit(2) for this, while AMD may
* use a completely different MSR and bit dependent on family.
*/
- if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL))
+ if (!static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) &&
+ !static_cpu_has(X86_FEATURE_AMD_SSBD)) {
x86_amd_ssb_disable();
- else {
+ } else {
x86_spec_ctrl_base |= SPEC_CTRL_SSBD;
x86_spec_ctrl_mask |= SPEC_CTRL_SSBD;
wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);