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-rw-r--r--arch/x86/kernel/Makefile5
-rw-r--r--arch/x86/kernel/alternative.c7
-rw-r--r--arch/x86/kernel/apic/apic.c49
-rw-r--r--arch/x86/kernel/apic/vector.c7
-rw-r--r--arch/x86/kernel/cpu/amd.c28
-rw-r--r--arch/x86/kernel/cpu/bugs.c221
-rw-r--r--arch/x86/kernel/cpu/common.c3
-rw-r--r--arch/x86/kernel/cpu/intel_rdt.c8
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c5
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c13
-rw-r--r--arch/x86/kernel/cpu/scattered.c1
-rw-r--r--arch/x86/kernel/ftrace_32.S6
-rw-r--r--arch/x86/kernel/ftrace_64.S32
-rw-r--r--arch/x86/kernel/head64.c4
-rw-r--r--arch/x86/kernel/idt.c12
-rw-r--r--arch/x86/kernel/irq_32.c9
-rw-r--r--arch/x86/kernel/irqinit.c3
-rw-r--r--arch/x86/kernel/kprobes/opt.c23
-rw-r--r--arch/x86/kernel/process.c25
-rw-r--r--arch/x86/kernel/setup.c10
-rw-r--r--arch/x86/kernel/tboot.c11
-rw-r--r--arch/x86/kernel/tsc.c9
-rw-r--r--arch/x86/kernel/unwind_orc.c48
-rw-r--r--arch/x86/kernel/vmlinux.lds.S6
24 files changed, 481 insertions, 64 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 81bb565f4497..7e2baf7304ae 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -29,10 +29,13 @@ KASAN_SANITIZE_stacktrace.o := n
KASAN_SANITIZE_paravirt.o := n
OBJECT_FILES_NON_STANDARD_relocate_kernel_$(BITS).o := y
-OBJECT_FILES_NON_STANDARD_ftrace_$(BITS).o := y
OBJECT_FILES_NON_STANDARD_test_nx.o := y
OBJECT_FILES_NON_STANDARD_paravirt_patch_$(BITS).o := y
+ifdef CONFIG_FRAME_POINTER
+OBJECT_FILES_NON_STANDARD_ftrace_$(BITS).o := y
+endif
+
# If instrumentation of this dir is enabled, boot hangs during first second.
# Probably could be more selective here, but note that files related to irqs,
# boot, dumpstack/stacktrace, etc are either non-interesting or can lead to
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index dbaf14d69ebd..4817d743c263 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -344,9 +344,12 @@ done:
static void __init_or_module noinline optimize_nops(struct alt_instr *a, u8 *instr)
{
unsigned long flags;
+ int i;
- if (instr[0] != 0x90)
- return;
+ for (i = 0; i < a->padlen; i++) {
+ if (instr[i] != 0x90)
+ return;
+ }
local_irq_save(flags);
add_nops(instr + (a->instrlen - a->padlen), a->padlen);
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 880441f24146..25ddf02598d2 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1286,6 +1286,55 @@ static int __init apic_intr_mode_select(void)
return APIC_SYMMETRIC_IO;
}
+/*
+ * An initial setup of the virtual wire mode.
+ */
+void __init init_bsp_APIC(void)
+{
+ unsigned int value;
+
+ /*
+ * Don't do the setup now if we have a SMP BIOS as the
+ * through-I/O-APIC virtual wire mode might be active.
+ */
+ if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
+ return;
+
+ /*
+ * Do not trust the local APIC being empty at bootup.
+ */
+ clear_local_APIC();
+
+ /*
+ * Enable APIC.
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+
+#ifdef CONFIG_X86_32
+ /* This bit is reserved on P4/Xeon and should be cleared */
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
+ (boot_cpu_data.x86 == 15))
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
+ else
+#endif
+ value |= APIC_SPIV_FOCUS_DISABLED;
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write(APIC_SPIV, value);
+
+ /*
+ * Set up the virtual wire mode.
+ */
+ apic_write(APIC_LVT0, APIC_DM_EXTINT);
+ value = APIC_DM_NMI;
+ if (!lapic_is_integrated()) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ if (apic_extnmi == APIC_EXTNMI_NONE)
+ value |= APIC_LVT_MASKED;
+ apic_write(APIC_LVT1, value);
+}
+
/* Init the interrupt delivery mode for the BSP */
void __init apic_intr_mode_init(void)
{
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index f8b03bb8e725..3cc471beb50b 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -542,14 +542,17 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
err = assign_irq_vector_policy(irqd, info);
trace_vector_setup(virq + i, false, err);
- if (err)
+ if (err) {
+ irqd->chip_data = NULL;
+ free_apic_chip_data(apicd);
goto error;
+ }
}
return 0;
error:
- x86_vector_free_irqs(domain, virq, i + 1);
+ x86_vector_free_irqs(domain, virq, i);
return err;
}
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index bcb75dc97d44..ea831c858195 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -829,8 +829,32 @@ static void init_amd(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_K8);
if (cpu_has(c, X86_FEATURE_XMM2)) {
- /* MFENCE stops RDTSC speculation */
- set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
+ unsigned long long val;
+ int ret;
+
+ /*
+ * A serializing LFENCE has less overhead than MFENCE, so
+ * use it for execution serialization. On families which
+ * don't have that MSR, LFENCE is already serializing.
+ * msr_set_bit() uses the safe accessors, too, even if the MSR
+ * is not present.
+ */
+ msr_set_bit(MSR_F10H_DECFG,
+ MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT);
+
+ /*
+ * Verify that the MSR write was successful (could be running
+ * under a hypervisor) and only then assume that LFENCE is
+ * serializing.
+ */
+ ret = rdmsrl_safe(MSR_F10H_DECFG, &val);
+ if (!ret && (val & MSR_F10H_DECFG_LFENCE_SERIALIZE)) {
+ /* A serializing LFENCE stops RDTSC speculation */
+ set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+ } else {
+ /* MFENCE stops RDTSC speculation */
+ set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
+ }
}
/*
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index ba0b2424c9b0..390b3dc3d438 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -10,6 +10,10 @@
*/
#include <linux/init.h>
#include <linux/utsname.h>
+#include <linux/cpu.h>
+
+#include <asm/nospec-branch.h>
+#include <asm/cmdline.h>
#include <asm/bugs.h>
#include <asm/processor.h>
#include <asm/processor-flags.h>
@@ -19,6 +23,9 @@
#include <asm/alternative.h>
#include <asm/pgtable.h>
#include <asm/set_memory.h>
+#include <asm/intel-family.h>
+
+static void __init spectre_v2_select_mitigation(void);
void __init check_bugs(void)
{
@@ -29,6 +36,9 @@ void __init check_bugs(void)
print_cpu_info(&boot_cpu_data);
}
+ /* Select the proper spectre mitigation before patching alternatives */
+ spectre_v2_select_mitigation();
+
#ifdef CONFIG_X86_32
/*
* Check whether we are able to run this kernel safely on SMP.
@@ -60,3 +70,214 @@ void __init check_bugs(void)
set_memory_4k((unsigned long)__va(0), 1);
#endif
}
+
+/* The kernel command line selection */
+enum spectre_v2_mitigation_cmd {
+ SPECTRE_V2_CMD_NONE,
+ SPECTRE_V2_CMD_AUTO,
+ SPECTRE_V2_CMD_FORCE,
+ SPECTRE_V2_CMD_RETPOLINE,
+ SPECTRE_V2_CMD_RETPOLINE_GENERIC,
+ SPECTRE_V2_CMD_RETPOLINE_AMD,
+};
+
+static const char *spectre_v2_strings[] = {
+ [SPECTRE_V2_NONE] = "Vulnerable",
+ [SPECTRE_V2_RETPOLINE_MINIMAL] = "Vulnerable: Minimal generic ASM retpoline",
+ [SPECTRE_V2_RETPOLINE_MINIMAL_AMD] = "Vulnerable: Minimal AMD ASM retpoline",
+ [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline",
+ [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline",
+};
+
+#undef pr_fmt
+#define pr_fmt(fmt) "Spectre V2 mitigation: " fmt
+
+static enum spectre_v2_mitigation spectre_v2_enabled = SPECTRE_V2_NONE;
+
+static void __init spec2_print_if_insecure(const char *reason)
+{
+ if (boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ pr_info("%s\n", reason);
+}
+
+static void __init spec2_print_if_secure(const char *reason)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ pr_info("%s\n", reason);
+}
+
+static inline bool retp_compiler(void)
+{
+ return __is_defined(RETPOLINE);
+}
+
+static inline bool match_option(const char *arg, int arglen, const char *opt)
+{
+ int len = strlen(opt);
+
+ return len == arglen && !strncmp(arg, opt, len);
+}
+
+static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
+{
+ char arg[20];
+ int ret;
+
+ ret = cmdline_find_option(boot_command_line, "spectre_v2", arg,
+ sizeof(arg));
+ if (ret > 0) {
+ if (match_option(arg, ret, "off")) {
+ goto disable;
+ } else if (match_option(arg, ret, "on")) {
+ spec2_print_if_secure("force enabled on command line.");
+ return SPECTRE_V2_CMD_FORCE;
+ } else if (match_option(arg, ret, "retpoline")) {
+ spec2_print_if_insecure("retpoline selected on command line.");
+ return SPECTRE_V2_CMD_RETPOLINE;
+ } else if (match_option(arg, ret, "retpoline,amd")) {
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
+ pr_err("retpoline,amd selected but CPU is not AMD. Switching to AUTO select\n");
+ return SPECTRE_V2_CMD_AUTO;
+ }
+ spec2_print_if_insecure("AMD retpoline selected on command line.");
+ return SPECTRE_V2_CMD_RETPOLINE_AMD;
+ } else if (match_option(arg, ret, "retpoline,generic")) {
+ spec2_print_if_insecure("generic retpoline selected on command line.");
+ return SPECTRE_V2_CMD_RETPOLINE_GENERIC;
+ } else if (match_option(arg, ret, "auto")) {
+ return SPECTRE_V2_CMD_AUTO;
+ }
+ }
+
+ if (!cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
+ return SPECTRE_V2_CMD_AUTO;
+disable:
+ spec2_print_if_insecure("disabled on command line.");
+ return SPECTRE_V2_CMD_NONE;
+}
+
+/* Check for Skylake-like CPUs (for RSB handling) */
+static bool __init is_skylake_era(void)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_data.x86 == 6) {
+ switch (boot_cpu_data.x86_model) {
+ case INTEL_FAM6_SKYLAKE_MOBILE:
+ case INTEL_FAM6_SKYLAKE_DESKTOP:
+ case INTEL_FAM6_SKYLAKE_X:
+ case INTEL_FAM6_KABYLAKE_MOBILE:
+ case INTEL_FAM6_KABYLAKE_DESKTOP:
+ return true;
+ }
+ }
+ return false;
+}
+
+static void __init spectre_v2_select_mitigation(void)
+{
+ enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
+ enum spectre_v2_mitigation mode = SPECTRE_V2_NONE;
+
+ /*
+ * If the CPU is not affected and the command line mode is NONE or AUTO
+ * then nothing to do.
+ */
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2) &&
+ (cmd == SPECTRE_V2_CMD_NONE || cmd == SPECTRE_V2_CMD_AUTO))
+ return;
+
+ switch (cmd) {
+ case SPECTRE_V2_CMD_NONE:
+ return;
+
+ case SPECTRE_V2_CMD_FORCE:
+ /* FALLTRHU */
+ case SPECTRE_V2_CMD_AUTO:
+ goto retpoline_auto;
+
+ case SPECTRE_V2_CMD_RETPOLINE_AMD:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_amd;
+ break;
+ case SPECTRE_V2_CMD_RETPOLINE_GENERIC:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_generic;
+ break;
+ case SPECTRE_V2_CMD_RETPOLINE:
+ if (IS_ENABLED(CONFIG_RETPOLINE))
+ goto retpoline_auto;
+ break;
+ }
+ pr_err("kernel not compiled with retpoline; no mitigation available!");
+ return;
+
+retpoline_auto:
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ retpoline_amd:
+ if (!boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) {
+ pr_err("LFENCE not serializing. Switching to generic retpoline\n");
+ goto retpoline_generic;
+ }
+ mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_AMD :
+ SPECTRE_V2_RETPOLINE_MINIMAL_AMD;
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE_AMD);
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+ } else {
+ retpoline_generic:
+ mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_GENERIC :
+ SPECTRE_V2_RETPOLINE_MINIMAL;
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+ }
+
+ spectre_v2_enabled = mode;
+ pr_info("%s\n", spectre_v2_strings[mode]);
+
+ /*
+ * If neither SMEP or KPTI are available, there is a risk of
+ * hitting userspace addresses in the RSB after a context switch
+ * from a shallow call stack to a deeper one. To prevent this fill
+ * the entire RSB, even when using IBRS.
+ *
+ * Skylake era CPUs have a separate issue with *underflow* of the
+ * RSB, when they will predict 'ret' targets from the generic BTB.
+ * The proper mitigation for this is IBRS. If IBRS is not supported
+ * or deactivated in favour of retpolines the RSB fill on context
+ * switch is required.
+ */
+ if ((!boot_cpu_has(X86_FEATURE_PTI) &&
+ !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) {
+ setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+ pr_info("Filling RSB on context switch\n");
+ }
+}
+
+#undef pr_fmt
+
+#ifdef CONFIG_SYSFS
+ssize_t cpu_show_meltdown(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN))
+ return sprintf(buf, "Not affected\n");
+ if (boot_cpu_has(X86_FEATURE_PTI))
+ return sprintf(buf, "Mitigation: PTI\n");
+ return sprintf(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_spectre_v1(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1))
+ return sprintf(buf, "Not affected\n");
+ return sprintf(buf, "Vulnerable\n");
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
+ return sprintf(buf, "Not affected\n");
+
+ return sprintf(buf, "%s\n", spectre_v2_strings[spectre_v2_enabled]);
+}
+#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 39d7ea865207..ef29ad001991 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -926,6 +926,9 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
if (c->x86_vendor != X86_VENDOR_AMD)
setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
+ setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
+ setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
+
fpu__init_system(c);
#ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/cpu/intel_rdt.c b/arch/x86/kernel/cpu/intel_rdt.c
index 88dcf8479013..99442370de40 100644
--- a/arch/x86/kernel/cpu/intel_rdt.c
+++ b/arch/x86/kernel/cpu/intel_rdt.c
@@ -525,10 +525,6 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
*/
if (static_branch_unlikely(&rdt_mon_enable_key))
rmdir_mondata_subdir_allrdtgrp(r, d->id);
- kfree(d->ctrl_val);
- kfree(d->rmid_busy_llc);
- kfree(d->mbm_total);
- kfree(d->mbm_local);
list_del(&d->list);
if (is_mbm_enabled())
cancel_delayed_work(&d->mbm_over);
@@ -545,6 +541,10 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
cancel_delayed_work(&d->cqm_limbo);
}
+ kfree(d->ctrl_val);
+ kfree(d->rmid_busy_llc);
+ kfree(d->mbm_total);
+ kfree(d->mbm_local);
kfree(d);
return;
}
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index b1d616d08eee..868e412b4f0c 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1785,6 +1785,11 @@ static void unexpected_machine_check(struct pt_regs *regs, long error_code)
void (*machine_check_vector)(struct pt_regs *, long error_code) =
unexpected_machine_check;
+dotraplinkage void do_mce(struct pt_regs *regs, long error_code)
+{
+ machine_check_vector(regs, error_code);
+}
+
/*
* Called for each booted CPU to set up machine checks.
* Must be called with preempt off:
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 8ccdca6d3f9e..d9e460fc7a3b 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -910,8 +910,17 @@ static bool is_blacklisted(unsigned int cpu)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);
- if (c->x86 == 6 && c->x86_model == INTEL_FAM6_BROADWELL_X) {
- pr_err_once("late loading on model 79 is disabled.\n");
+ /*
+ * Late loading on model 79 with microcode revision less than 0x0b000021
+ * may result in a system hang. This behavior is documented in item
+ * BDF90, #334165 (Intel Xeon Processor E7-8800/4800 v4 Product Family).
+ */
+ if (c->x86 == 6 &&
+ c->x86_model == INTEL_FAM6_BROADWELL_X &&
+ c->x86_mask == 0x01 &&
+ c->microcode < 0x0b000021) {
+ pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
+ pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
return true;
}
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 05459ad3db46..d0e69769abfd 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -21,7 +21,6 @@ struct cpuid_bit {
static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
- { X86_FEATURE_INTEL_PT, CPUID_EBX, 25, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4VNNIW, CPUID_EDX, 2, 0x00000007, 0 },
{ X86_FEATURE_AVX512_4FMAPS, CPUID_EDX, 3, 0x00000007, 0 },
{ X86_FEATURE_CAT_L3, CPUID_EBX, 1, 0x00000010, 0 },
diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S
index b6c6468e10bc..4c8440de3355 100644
--- a/arch/x86/kernel/ftrace_32.S
+++ b/arch/x86/kernel/ftrace_32.S
@@ -8,6 +8,7 @@
#include <asm/segment.h>
#include <asm/export.h>
#include <asm/ftrace.h>
+#include <asm/nospec-branch.h>
#ifdef CC_USING_FENTRY
# define function_hook __fentry__
@@ -197,7 +198,8 @@ ftrace_stub:
movl 0x4(%ebp), %edx
subl $MCOUNT_INSN_SIZE, %eax
- call *ftrace_trace_function
+ movl ftrace_trace_function, %ecx
+ CALL_NOSPEC %ecx
popl %edx
popl %ecx
@@ -241,5 +243,5 @@ return_to_handler:
movl %eax, %ecx
popl %edx
popl %eax
- jmp *%ecx
+ JMP_NOSPEC %ecx
#endif
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
index c832291d948a..ef61f540cf0a 100644
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -7,7 +7,8 @@
#include <asm/ptrace.h>
#include <asm/ftrace.h>
#include <asm/export.h>
-
+#include <asm/nospec-branch.h>
+#include <asm/unwind_hints.h>
.code64
.section .entry.text, "ax"
@@ -20,7 +21,6 @@ EXPORT_SYMBOL(__fentry__)
EXPORT_SYMBOL(mcount)
#endif
-/* All cases save the original rbp (8 bytes) */
#ifdef CONFIG_FRAME_POINTER
# ifdef CC_USING_FENTRY
/* Save parent and function stack frames (rip and rbp) */
@@ -31,7 +31,7 @@ EXPORT_SYMBOL(mcount)
# endif
#else
/* No need to save a stack frame */
-# define MCOUNT_FRAME_SIZE 8
+# define MCOUNT_FRAME_SIZE 0
#endif /* CONFIG_FRAME_POINTER */
/* Size of stack used to save mcount regs in save_mcount_regs */
@@ -64,10 +64,10 @@ EXPORT_SYMBOL(mcount)
*/
.macro save_mcount_regs added=0
- /* Always save the original rbp */
+#ifdef CONFIG_FRAME_POINTER
+ /* Save the original rbp */
pushq %rbp
-#ifdef CONFIG_FRAME_POINTER
/*
* Stack traces will stop at the ftrace trampoline if the frame pointer
* is not set up properly. If fentry is used, we need to save a frame
@@ -105,7 +105,11 @@ EXPORT_SYMBOL(mcount)
* Save the original RBP. Even though the mcount ABI does not
* require this, it helps out callers.
*/
+#ifdef CONFIG_FRAME_POINTER
movq MCOUNT_REG_SIZE-8(%rsp), %rdx
+#else
+ movq %rbp, %rdx
+#endif
movq %rdx, RBP(%rsp)
/* Copy the parent address into %rsi (second parameter) */
@@ -148,7 +152,7 @@ EXPORT_SYMBOL(mcount)
ENTRY(function_hook)
retq
-END(function_hook)
+ENDPROC(function_hook)
ENTRY(ftrace_caller)
/* save_mcount_regs fills in first two parameters */
@@ -184,7 +188,7 @@ GLOBAL(ftrace_graph_call)
/* This is weak to keep gas from relaxing the jumps */
WEAK(ftrace_stub)
retq
-END(ftrace_caller)
+ENDPROC(ftrace_caller)
ENTRY(ftrace_regs_caller)
/* Save the current flags before any operations that can change them */
@@ -255,7 +259,7 @@ GLOBAL(ftrace_regs_caller_end)
jmp ftrace_epilogue
-END(ftrace_regs_caller)
+ENDPROC(ftrace_regs_caller)
#else /* ! CONFIG_DYNAMIC_FTRACE */
@@ -286,8 +290,8 @@ trace:
* ip and parent ip are used and the list function is called when
* function tracing is enabled.
*/
- call *ftrace_trace_function
-
+ movq ftrace_trace_function, %r8
+ CALL_NOSPEC %r8
restore_mcount_regs
jmp fgraph_trace
@@ -313,9 +317,10 @@ ENTRY(ftrace_graph_caller)
restore_mcount_regs
retq
-END(ftrace_graph_caller)
+ENDPROC(ftrace_graph_caller)
-GLOBAL(return_to_handler)
+ENTRY(return_to_handler)
+ UNWIND_HINT_EMPTY
subq $24, %rsp
/* Save the return values */
@@ -329,5 +334,6 @@ GLOBAL(return_to_handler)
movq 8(%rsp), %rdx
movq (%rsp), %rax
addq $24, %rsp
- jmp *%rdi
+ JMP_NOSPEC %rdi
+END(return_to_handler)
#endif
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 6a5d757b9cfd..7ba5d819ebe3 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -157,8 +157,8 @@ unsigned long __head __startup_64(unsigned long physaddr,
p = fixup_pointer(&phys_base, physaddr);
*p += load_delta - sme_get_me_mask();
- /* Encrypt the kernel (if SME is active) */
- sme_encrypt_kernel();
+ /* Encrypt the kernel and related (if SME is active) */
+ sme_encrypt_kernel(bp);
/*
* Return the SME encryption mask (if SME is active) to be used as a
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index d985cef3984f..56d99be3706a 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -56,7 +56,7 @@ struct idt_data {
* Early traps running on the DEFAULT_STACK because the other interrupt
* stacks work only after cpu_init().
*/
-static const __initdata struct idt_data early_idts[] = {
+static const __initconst struct idt_data early_idts[] = {
INTG(X86_TRAP_DB, debug),
SYSG(X86_TRAP_BP, int3),
#ifdef CONFIG_X86_32
@@ -70,7 +70,7 @@ static const __initdata struct idt_data early_idts[] = {
* the traps which use them are reinitialized with IST after cpu_init() has
* set up TSS.
*/
-static const __initdata struct idt_data def_idts[] = {
+static const __initconst struct idt_data def_idts[] = {
INTG(X86_TRAP_DE, divide_error),
INTG(X86_TRAP_NMI, nmi),
INTG(X86_TRAP_BR, bounds),
@@ -108,7 +108,7 @@ static const __initdata struct idt_data def_idts[] = {
/*
* The APIC and SMP idt entries
*/
-static const __initdata struct idt_data apic_idts[] = {
+static const __initconst struct idt_data apic_idts[] = {
#ifdef CONFIG_SMP
INTG(RESCHEDULE_VECTOR, reschedule_interrupt),
INTG(CALL_FUNCTION_VECTOR, call_function_interrupt),
@@ -150,7 +150,7 @@ static const __initdata struct idt_data apic_idts[] = {
* Early traps running on the DEFAULT_STACK because the other interrupt
* stacks work only after cpu_init().
*/
-static const __initdata struct idt_data early_pf_idts[] = {
+static const __initconst struct idt_data early_pf_idts[] = {
INTG(X86_TRAP_PF, page_fault),
};
@@ -158,7 +158,7 @@ static const __initdata struct idt_data early_pf_idts[] = {
* Override for the debug_idt. Same as the default, but with interrupt
* stack set to DEFAULT_STACK (0). Required for NMI trap handling.
*/
-static const __initdata struct idt_data dbg_idts[] = {
+static const __initconst struct idt_data dbg_idts[] = {
INTG(X86_TRAP_DB, debug),
INTG(X86_TRAP_BP, int3),
};
@@ -180,7 +180,7 @@ gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss;
* The exceptions which use Interrupt stacks. They are setup after
* cpu_init() when the TSS has been initialized.
*/
-static const __initdata struct idt_data ist_idts[] = {
+static const __initconst struct idt_data ist_idts[] = {
ISTG(X86_TRAP_DB, debug, DEBUG_STACK),
ISTG(X86_TRAP_NMI, nmi, NMI_STACK),
SISTG(X86_TRAP_BP, int3, DEBUG_STACK),
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index a83b3346a0e1..c1bdbd3d3232 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -20,6 +20,7 @@
#include <linux/mm.h>
#include <asm/apic.h>
+#include <asm/nospec-branch.h>
#ifdef CONFIG_DEBUG_STACKOVERFLOW
@@ -55,11 +56,11 @@ DEFINE_PER_CPU(struct irq_stack *, softirq_stack);
static void call_on_stack(void *func, void *stack)
{
asm volatile("xchgl %%ebx,%%esp \n"
- "call *%%edi \n"
+ CALL_NOSPEC
"movl %%ebx,%%esp \n"
: "=b" (stack)
: "0" (stack),
- "D"(func)
+ [thunk_target] "D"(func)
: "memory", "cc", "edx", "ecx", "eax");
}
@@ -95,11 +96,11 @@ static inline int execute_on_irq_stack(int overflow, struct irq_desc *desc)
call_on_stack(print_stack_overflow, isp);
asm volatile("xchgl %%ebx,%%esp \n"
- "call *%%edi \n"
+ CALL_NOSPEC
"movl %%ebx,%%esp \n"
: "=a" (arg1), "=b" (isp)
: "0" (desc), "1" (isp),
- "D" (desc->handle_irq)
+ [thunk_target] "D" (desc->handle_irq)
: "memory", "cc", "ecx");
return 1;
}
diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index 8da3e909e967..a539410c4ea9 100644
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -61,6 +61,9 @@ void __init init_ISA_irqs(void)
struct irq_chip *chip = legacy_pic->chip;
int i;
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
+ init_bsp_APIC();
+#endif
legacy_pic->init(0);
for (i = 0; i < nr_legacy_irqs(); i++)
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index e941136e24d8..203d398802a3 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -40,6 +40,7 @@
#include <asm/debugreg.h>
#include <asm/set_memory.h>
#include <asm/sections.h>
+#include <asm/nospec-branch.h>
#include "common.h"
@@ -203,7 +204,7 @@ static int copy_optimized_instructions(u8 *dest, u8 *src, u8 *real)
}
/* Check whether insn is indirect jump */
-static int insn_is_indirect_jump(struct insn *insn)
+static int __insn_is_indirect_jump(struct insn *insn)
{
return ((insn->opcode.bytes[0] == 0xff &&
(X86_MODRM_REG(insn->modrm.value) & 6) == 4) || /* Jump */
@@ -237,6 +238,26 @@ static int insn_jump_into_range(struct insn *insn, unsigned long start, int len)
return (start <= target && target <= start + len);
}
+static int insn_is_indirect_jump(struct insn *insn)
+{
+ int ret = __insn_is_indirect_jump(insn);
+
+#ifdef CONFIG_RETPOLINE
+ /*
+ * Jump to x86_indirect_thunk_* is treated as an indirect jump.
+ * Note that even with CONFIG_RETPOLINE=y, the kernel compiled with
+ * older gcc may use indirect jump. So we add this check instead of
+ * replace indirect-jump check.
+ */
+ if (!ret)
+ ret = insn_jump_into_range(insn,
+ (unsigned long)__indirect_thunk_start,
+ (unsigned long)__indirect_thunk_end -
+ (unsigned long)__indirect_thunk_start);
+#endif
+ return ret;
+}
+
/* Decode whole function to ensure any instructions don't jump into target */
static int can_optimize(unsigned long paddr)
{
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 832a6acd730f..cb368c2a22ab 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -380,19 +380,24 @@ void stop_this_cpu(void *dummy)
disable_local_APIC();
mcheck_cpu_clear(this_cpu_ptr(&cpu_info));
+ /*
+ * Use wbinvd on processors that support SME. This provides support
+ * for performing a successful kexec when going from SME inactive
+ * to SME active (or vice-versa). The cache must be cleared so that
+ * if there are entries with the same physical address, both with and
+ * without the encryption bit, they don't race each other when flushed
+ * and potentially end up with the wrong entry being committed to
+ * memory.
+ */
+ if (boot_cpu_has(X86_FEATURE_SME))
+ native_wbinvd();
for (;;) {
/*
- * Use wbinvd followed by hlt to stop the processor. This
- * provides support for kexec on a processor that supports
- * SME. With kexec, going from SME inactive to SME active
- * requires clearing cache entries so that addresses without
- * the encryption bit set don't corrupt the same physical
- * address that has the encryption bit set when caches are
- * flushed. To achieve this a wbinvd is performed followed by
- * a hlt. Even if the processor is not in the kexec/SME
- * scenario this only adds a wbinvd to a halting processor.
+ * Use native_halt() so that memory contents don't change
+ * (stack usage and variables) after possibly issuing the
+ * native_wbinvd() above.
*/
- asm volatile("wbinvd; hlt" : : : "memory");
+ native_halt();
}
}
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 145810b0edf6..68d7ab81c62f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -364,16 +364,6 @@ static void __init reserve_initrd(void)
!ramdisk_image || !ramdisk_size)
return; /* No initrd provided by bootloader */
- /*
- * If SME is active, this memory will be marked encrypted by the
- * kernel when it is accessed (including relocation). However, the
- * ramdisk image was loaded decrypted by the bootloader, so make
- * sure that it is encrypted before accessing it. For SEV the
- * ramdisk will already be encrypted, so only do this for SME.
- */
- if (sme_active())
- sme_early_encrypt(ramdisk_image, ramdisk_end - ramdisk_image);
-
initrd_start = 0;
mapped_size = memblock_mem_size(max_pfn_mapped);
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index a4eb27918ceb..a2486f444073 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -138,6 +138,17 @@ static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
return -1;
set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
pte_unmap(pte);
+
+ /*
+ * PTI poisons low addresses in the kernel page tables in the
+ * name of making them unusable for userspace. To execute
+ * code at such a low address, the poison must be cleared.
+ *
+ * Note: 'pgd' actually gets set in p4d_alloc() _or_
+ * pud_alloc() depending on 4/5-level paging.
+ */
+ pgd->pgd &= ~_PAGE_NX;
+
return 0;
}
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 8ea117f8142e..e169e85db434 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -602,7 +602,6 @@ unsigned long native_calibrate_tsc(void)
case INTEL_FAM6_KABYLAKE_DESKTOP:
crystal_khz = 24000; /* 24.0 MHz */
break;
- case INTEL_FAM6_SKYLAKE_X:
case INTEL_FAM6_ATOM_DENVERTON:
crystal_khz = 25000; /* 25.0 MHz */
break;
@@ -612,6 +611,8 @@ unsigned long native_calibrate_tsc(void)
}
}
+ if (crystal_khz == 0)
+ return 0;
/*
* TSC frequency determined by CPUID is a "hardware reported"
* frequency and is the most accurate one so far we have. This
@@ -1315,6 +1316,12 @@ void __init tsc_init(void)
(unsigned long)cpu_khz / 1000,
(unsigned long)cpu_khz % 1000);
+ if (cpu_khz != tsc_khz) {
+ pr_info("Detected %lu.%03lu MHz TSC",
+ (unsigned long)tsc_khz / 1000,
+ (unsigned long)tsc_khz % 1000);
+ }
+
/* Sanitize TSC ADJUST before cyc2ns gets initialized */
tsc_store_and_check_tsc_adjust(true);
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index be86a865087a..1f9188f5357c 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -74,8 +74,50 @@ static struct orc_entry *orc_module_find(unsigned long ip)
}
#endif
+#ifdef CONFIG_DYNAMIC_FTRACE
+static struct orc_entry *orc_find(unsigned long ip);
+
+/*
+ * Ftrace dynamic trampolines do not have orc entries of their own.
+ * But they are copies of the ftrace entries that are static and
+ * defined in ftrace_*.S, which do have orc entries.
+ *
+ * If the undwinder comes across a ftrace trampoline, then find the
+ * ftrace function that was used to create it, and use that ftrace
+ * function's orc entrie, as the placement of the return code in
+ * the stack will be identical.
+ */
+static struct orc_entry *orc_ftrace_find(unsigned long ip)
+{
+ struct ftrace_ops *ops;
+ unsigned long caller;
+
+ ops = ftrace_ops_trampoline(ip);
+ if (!ops)
+ return NULL;
+
+ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
+ caller = (unsigned long)ftrace_regs_call;
+ else
+ caller = (unsigned long)ftrace_call;
+
+ /* Prevent unlikely recursion */
+ if (ip == caller)
+ return NULL;
+
+ return orc_find(caller);
+}
+#else
+static struct orc_entry *orc_ftrace_find(unsigned long ip)
+{
+ return NULL;
+}
+#endif
+
static struct orc_entry *orc_find(unsigned long ip)
{
+ static struct orc_entry *orc;
+
if (!orc_init)
return NULL;
@@ -111,7 +153,11 @@ static struct orc_entry *orc_find(unsigned long ip)
__stop_orc_unwind_ip - __start_orc_unwind_ip, ip);
/* Module lookup: */
- return orc_module_find(ip);
+ orc = orc_module_find(ip);
+ if (orc)
+ return orc;
+
+ return orc_ftrace_find(ip);
}
static void orc_sort_swap(void *_a, void *_b, int size)
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 1e413a9326aa..9b138a06c1a4 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -124,6 +124,12 @@ SECTIONS
ASSERT(. - _entry_trampoline == PAGE_SIZE, "entry trampoline is too big");
#endif
+#ifdef CONFIG_RETPOLINE
+ __indirect_thunk_start = .;
+ *(.text.__x86.indirect_thunk)
+ __indirect_thunk_end = .;
+#endif
+
/* End of text section */
_etext = .;
} :text = 0x9090