Merge tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more x86 updates from Thomas Gleixner:
"A set of fixes and updates for x86:
- Unbreak paravirt VDSO clocks.
While the VDSO code was moved into lib for sharing a subtle check
for the validity of paravirt clocks got replaced. While the
replacement works perfectly fine for bare metal as the update of
the VDSO clock mode is synchronous, it fails for paravirt clocks
because the hypervisor can invalidate them asynchronously.
Bring it back as an optional function so it does not inflict this
on architectures which are free of PV damage.
- Fix the jiffies to jiffies64 mapping on 64bit so it does not
trigger an ODR violation on newer compilers
- Three fixes for the SSBD and *IB* speculation mitigation maze to
ensure consistency, not disabling of some *IB* variants wrongly and
to prevent a rogue cross process shutdown of SSBD. All marked for
stable.
- Add yet more CPU models to the splitlock detection capable list
!@#%$!
- Bring the pr_info() back which tells that TSC deadline timer is
enabled.
- Reboot quirk for MacBook6,1"
* tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Unbreak paravirt VDSO clocks
lib/vdso: Provide sanity check for cycles (again)
clocksource: Remove obsolete ifdef
x86_64: Fix jiffies ODR violation
x86/speculation: PR_SPEC_FORCE_DISABLE enforcement for indirect branches.
x86/speculation: Prevent rogue cross-process SSBD shutdown
x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.
x86/cpu: Add Sapphire Rapids CPU model number
x86/split_lock: Add Icelake microserver and Tigerlake CPU models
x86/apic: Make TSC deadline timer detection message visible
x86/reboot/quirks: Add MacBook6,1 reboot quirk
diff --git a/arch/x86/include/asm/intel-family.h b/arch/x86/include/asm/intel-family.h
index 8f1e94f..a338a6d 100644
--- a/arch/x86/include/asm/intel-family.h
+++ b/arch/x86/include/asm/intel-family.h
@@ -89,6 +89,8 @@
#define INTEL_FAM6_COMETLAKE 0xA5
#define INTEL_FAM6_COMETLAKE_L 0xA6
+#define INTEL_FAM6_SAPPHIRERAPIDS_X 0x8F
+
/* "Small Core" Processors (Atom) */
#define INTEL_FAM6_ATOM_BONNELL 0x1C /* Diamondville, Pineview */
diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h
index 9a6dc9b..fb81fea 100644
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -271,6 +271,24 @@
return __vdso_data;
}
+static inline bool arch_vdso_clocksource_ok(const struct vdso_data *vd)
+{
+ return true;
+}
+#define vdso_clocksource_ok arch_vdso_clocksource_ok
+
+/*
+ * Clocksource read value validation to handle PV and HyperV clocksources
+ * which can be invalidated asynchronously and indicate invalidation by
+ * returning U64_MAX, which can be effectively tested by checking for a
+ * negative value after casting it to s64.
+ */
+static inline bool arch_vdso_cycles_ok(u64 cycles)
+{
+ return (s64)cycles >= 0;
+}
+#define vdso_cycles_ok arch_vdso_cycles_ok
+
/*
* x86 specific delta calculation.
*
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 4b1d31b..bf4acb0 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2060,7 +2060,7 @@
unsigned int new_apicid;
if (apic_validate_deadline_timer())
- pr_debug("TSC deadline timer available\n");
+ pr_info("TSC deadline timer available\n");
if (x2apic_mode) {
boot_cpu_physical_apicid = read_apic_id();
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index b6f887b..0b71970 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -588,7 +588,9 @@
static enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init =
SPECTRE_V2_NONE;
-static enum spectre_v2_user_mitigation spectre_v2_user __ro_after_init =
+static enum spectre_v2_user_mitigation spectre_v2_user_stibp __ro_after_init =
+ SPECTRE_V2_USER_NONE;
+static enum spectre_v2_user_mitigation spectre_v2_user_ibpb __ro_after_init =
SPECTRE_V2_USER_NONE;
#ifdef CONFIG_RETPOLINE
@@ -734,15 +736,6 @@
break;
}
- /*
- * At this point, an STIBP mode other than "off" has been set.
- * If STIBP support is not being forced, check if STIBP always-on
- * is preferred.
- */
- if (mode != SPECTRE_V2_USER_STRICT &&
- boot_cpu_has(X86_FEATURE_AMD_STIBP_ALWAYS_ON))
- mode = SPECTRE_V2_USER_STRICT_PREFERRED;
-
/* Initialize Indirect Branch Prediction Barrier */
if (boot_cpu_has(X86_FEATURE_IBPB)) {
setup_force_cpu_cap(X86_FEATURE_USE_IBPB);
@@ -765,23 +758,36 @@
pr_info("mitigation: Enabling %s Indirect Branch Prediction Barrier\n",
static_key_enabled(&switch_mm_always_ibpb) ?
"always-on" : "conditional");
+
+ spectre_v2_user_ibpb = mode;
}
- /* If enhanced IBRS is enabled no STIBP required */
- if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
+ /*
+ * If enhanced IBRS is enabled or SMT impossible, STIBP is not
+ * required.
+ */
+ if (!smt_possible || spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
return;
/*
- * If SMT is not possible or STIBP is not available clear the STIBP
- * mode.
+ * At this point, an STIBP mode other than "off" has been set.
+ * If STIBP support is not being forced, check if STIBP always-on
+ * is preferred.
*/
- if (!smt_possible || !boot_cpu_has(X86_FEATURE_STIBP))
+ if (mode != SPECTRE_V2_USER_STRICT &&
+ boot_cpu_has(X86_FEATURE_AMD_STIBP_ALWAYS_ON))
+ mode = SPECTRE_V2_USER_STRICT_PREFERRED;
+
+ /*
+ * If STIBP is not available, clear the STIBP mode.
+ */
+ if (!boot_cpu_has(X86_FEATURE_STIBP))
mode = SPECTRE_V2_USER_NONE;
+
+ spectre_v2_user_stibp = mode;
+
set_mode:
- spectre_v2_user = mode;
- /* Only print the STIBP mode when SMT possible */
- if (smt_possible)
- pr_info("%s\n", spectre_v2_user_strings[mode]);
+ pr_info("%s\n", spectre_v2_user_strings[mode]);
}
static const char * const spectre_v2_strings[] = {
@@ -1014,7 +1020,7 @@
{
mutex_lock(&spec_ctrl_mutex);
- switch (spectre_v2_user) {
+ switch (spectre_v2_user_stibp) {
case SPECTRE_V2_USER_NONE:
break;
case SPECTRE_V2_USER_STRICT:
@@ -1257,14 +1263,19 @@
{
switch (ctrl) {
case PR_SPEC_ENABLE:
- if (spectre_v2_user == SPECTRE_V2_USER_NONE)
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+ spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
return 0;
/*
* Indirect branch speculation is always disabled in strict
- * mode.
+ * mode. It can neither be enabled if it was force-disabled
+ * by a previous prctl call.
+
*/
- if (spectre_v2_user == SPECTRE_V2_USER_STRICT ||
- spectre_v2_user == SPECTRE_V2_USER_STRICT_PREFERRED)
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED ||
+ task_spec_ib_force_disable(task))
return -EPERM;
task_clear_spec_ib_disable(task);
task_update_spec_tif(task);
@@ -1275,10 +1286,12 @@
* Indirect branch speculation is always allowed when
* mitigation is force disabled.
*/
- if (spectre_v2_user == SPECTRE_V2_USER_NONE)
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+ spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
return -EPERM;
- if (spectre_v2_user == SPECTRE_V2_USER_STRICT ||
- spectre_v2_user == SPECTRE_V2_USER_STRICT_PREFERRED)
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED)
return 0;
task_set_spec_ib_disable(task);
if (ctrl == PR_SPEC_FORCE_DISABLE)
@@ -1309,7 +1322,8 @@
{
if (ssb_mode == SPEC_STORE_BYPASS_SECCOMP)
ssb_prctl_set(task, PR_SPEC_FORCE_DISABLE);
- if (spectre_v2_user == SPECTRE_V2_USER_SECCOMP)
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_SECCOMP ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_SECCOMP)
ib_prctl_set(task, PR_SPEC_FORCE_DISABLE);
}
#endif
@@ -1340,22 +1354,24 @@
if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
return PR_SPEC_NOT_AFFECTED;
- switch (spectre_v2_user) {
- case SPECTRE_V2_USER_NONE:
+ if (spectre_v2_user_ibpb == SPECTRE_V2_USER_NONE &&
+ spectre_v2_user_stibp == SPECTRE_V2_USER_NONE)
return PR_SPEC_ENABLE;
- case SPECTRE_V2_USER_PRCTL:
- case SPECTRE_V2_USER_SECCOMP:
+ else if (spectre_v2_user_ibpb == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED)
+ return PR_SPEC_DISABLE;
+ else if (spectre_v2_user_ibpb == SPECTRE_V2_USER_PRCTL ||
+ spectre_v2_user_ibpb == SPECTRE_V2_USER_SECCOMP ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_PRCTL ||
+ spectre_v2_user_stibp == SPECTRE_V2_USER_SECCOMP) {
if (task_spec_ib_force_disable(task))
return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE;
if (task_spec_ib_disable(task))
return PR_SPEC_PRCTL | PR_SPEC_DISABLE;
return PR_SPEC_PRCTL | PR_SPEC_ENABLE;
- case SPECTRE_V2_USER_STRICT:
- case SPECTRE_V2_USER_STRICT_PREFERRED:
- return PR_SPEC_DISABLE;
- default:
+ } else
return PR_SPEC_NOT_AFFECTED;
- }
}
int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
@@ -1594,7 +1610,7 @@
if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
return "";
- switch (spectre_v2_user) {
+ switch (spectre_v2_user_stibp) {
case SPECTRE_V2_USER_NONE:
return ", STIBP: disabled";
case SPECTRE_V2_USER_STRICT:
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 63926c9..c25a67a 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -1142,9 +1142,12 @@
static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = {
X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, 0),
X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L, 0),
+ X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, 0),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT, 1),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D, 1),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_L, 1),
+ X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L, 1),
+ X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE, 1),
{}
};
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 8e3d034..f362ce0 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -545,28 +545,20 @@
lockdep_assert_irqs_disabled();
- /*
- * If TIF_SSBD is different, select the proper mitigation
- * method. Note that if SSBD mitigation is disabled or permanentely
- * enabled this branch can't be taken because nothing can set
- * TIF_SSBD.
- */
- if (tif_diff & _TIF_SSBD) {
- if (static_cpu_has(X86_FEATURE_VIRT_SSBD)) {
+ /* Handle change of TIF_SSBD depending on the mitigation method. */
+ if (static_cpu_has(X86_FEATURE_VIRT_SSBD)) {
+ if (tif_diff & _TIF_SSBD)
amd_set_ssb_virt_state(tifn);
- } else if (static_cpu_has(X86_FEATURE_LS_CFG_SSBD)) {
+ } else if (static_cpu_has(X86_FEATURE_LS_CFG_SSBD)) {
+ if (tif_diff & _TIF_SSBD)
amd_set_core_ssb_state(tifn);
- } else if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
- static_cpu_has(X86_FEATURE_AMD_SSBD)) {
- msr |= ssbd_tif_to_spec_ctrl(tifn);
- updmsr = true;
- }
+ } else if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
+ static_cpu_has(X86_FEATURE_AMD_SSBD)) {
+ updmsr |= !!(tif_diff & _TIF_SSBD);
+ msr |= ssbd_tif_to_spec_ctrl(tifn);
}
- /*
- * Only evaluate TIF_SPEC_IB if conditional STIBP is enabled,
- * otherwise avoid the MSR write.
- */
+ /* Only evaluate TIF_SPEC_IB if conditional STIBP is enabled. */
if (IS_ENABLED(CONFIG_SMP) &&
static_branch_unlikely(&switch_to_cond_stibp)) {
updmsr |= !!(tif_diff & _TIF_SPEC_IB);
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index e040ba6b..0ec7ced 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -197,6 +197,14 @@
DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
},
},
+ { /* Handle problems with rebooting on Apple MacBook6,1 */
+ .callback = set_pci_reboot,
+ .ident = "Apple MacBook6,1",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"),
+ },
+ },
{ /* Handle problems with rebooting on Apple MacBookPro5 */
.callback = set_pci_reboot,
.ident = "Apple MacBookPro5",
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index 371a6b3..e42faa7 100644
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -25,10 +25,6 @@
#include <asm/hpet.h>
#include <asm/time.h>
-#ifdef CONFIG_X86_64
-__visible volatile unsigned long jiffies __cacheline_aligned_in_smp = INITIAL_JIFFIES;
-#endif
-
unsigned long profile_pc(struct pt_regs *regs)
{
unsigned long pc = instruction_pointer(regs);
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 1bf7e31..7c35556 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -40,13 +40,13 @@
#ifdef CONFIG_X86_32
OUTPUT_ARCH(i386)
ENTRY(phys_startup_32)
-jiffies = jiffies_64;
#else
OUTPUT_ARCH(i386:x86-64)
ENTRY(phys_startup_64)
-jiffies_64 = jiffies;
#endif
+jiffies = jiffies_64;
+
#if defined(CONFIG_X86_64)
/*
* On 64-bit, align RODATA to 2MB so we retain large page mappings for
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 7cb09c4..02441ea 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -928,14 +928,12 @@
clocksource_arch_init(cs);
-#ifdef CONFIG_GENERIC_VDSO_CLOCK_MODE
if (cs->vdso_clock_mode < 0 ||
cs->vdso_clock_mode >= VDSO_CLOCKMODE_MAX) {
pr_warn("clocksource %s registered with invalid VDSO mode %d. Disabling VDSO support.\n",
cs->name, cs->vdso_clock_mode);
cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE;
}
-#endif
/* Initialize mult/shift and max_idle_ns */
__clocksource_update_freq_scale(cs, scale, freq);
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index 7938d3c..bcc9a98 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -38,6 +38,13 @@
}
#endif
+#ifndef vdso_cycles_ok
+static inline bool vdso_cycles_ok(u64 cycles)
+{
+ return true;
+}
+#endif
+
#ifdef CONFIG_TIME_NS
static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
struct __kernel_timespec *ts)
@@ -62,6 +69,8 @@
return -1;
cycles = __arch_get_hw_counter(vd->clock_mode);
+ if (unlikely(!vdso_cycles_ok(cycles)))
+ return -1;
ns = vdso_ts->nsec;
last = vd->cycle_last;
ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
@@ -130,6 +139,8 @@
return -1;
cycles = __arch_get_hw_counter(vd->clock_mode);
+ if (unlikely(!vdso_cycles_ok(cycles)))
+ return -1;
ns = vdso_ts->nsec;
last = vd->cycle_last;
ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
