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-rw-r--r--arch/x86/kernel/cpu/intel.c3
-rw-r--r--arch/x86/kernel/cpu/microcode/amd.c34
-rw-r--r--arch/x86/kernel/cpu/microcode/core.c76
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c4
-rw-r--r--arch/x86/kernel/idt.c2
-rw-r--r--arch/x86/kernel/pci-nommu.c19
-rw-r--r--arch/x86/kernel/traps.c15
-rw-r--r--arch/x86/kernel/vm86_32.c3
8 files changed, 79 insertions, 77 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 4aa9fd379390..c3af167d0a70 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -105,7 +105,7 @@ static void probe_xeon_phi_r3mwait(struct cpuinfo_x86 *c)
/*
* Early microcode releases for the Spectre v2 mitigation were broken.
* Information taken from;
- * - https://newsroom.intel.com/wp-content/uploads/sites/11/2018/01/microcode-update-guidance.pdf
+ * - https://newsroom.intel.com/wp-content/uploads/sites/11/2018/03/microcode-update-guidance.pdf
* - https://kb.vmware.com/s/article/52345
* - Microcode revisions observed in the wild
* - Release note from 20180108 microcode release
@@ -123,7 +123,6 @@ static const struct sku_microcode spectre_bad_microcodes[] = {
{ INTEL_FAM6_KABYLAKE_MOBILE, 0x09, 0x80 },
{ INTEL_FAM6_SKYLAKE_X, 0x03, 0x0100013e },
{ INTEL_FAM6_SKYLAKE_X, 0x04, 0x0200003c },
- { INTEL_FAM6_SKYLAKE_DESKTOP, 0x03, 0xc2 },
{ INTEL_FAM6_BROADWELL_CORE, 0x04, 0x28 },
{ INTEL_FAM6_BROADWELL_GT3E, 0x01, 0x1b },
{ INTEL_FAM6_BROADWELL_XEON_D, 0x02, 0x14 },
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index a998e1a7d46f..48179928ff38 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -339,7 +339,7 @@ int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax)
return -EINVAL;
ret = load_microcode_amd(true, x86_family(cpuid_1_eax), desc.data, desc.size);
- if (ret != UCODE_OK)
+ if (ret > UCODE_UPDATED)
return -EINVAL;
return 0;
@@ -683,27 +683,35 @@ static enum ucode_state __load_microcode_amd(u8 family, const u8 *data,
static enum ucode_state
load_microcode_amd(bool save, u8 family, const u8 *data, size_t size)
{
+ struct ucode_patch *p;
enum ucode_state ret;
/* free old equiv table */
free_equiv_cpu_table();
ret = __load_microcode_amd(family, data, size);
-
- if (ret != UCODE_OK)
+ if (ret != UCODE_OK) {
cleanup();
+ return ret;
+ }
-#ifdef CONFIG_X86_32
- /* save BSP's matching patch for early load */
- if (save) {
- struct ucode_patch *p = find_patch(0);
- if (p) {
- memset(amd_ucode_patch, 0, PATCH_MAX_SIZE);
- memcpy(amd_ucode_patch, p->data, min_t(u32, ksize(p->data),
- PATCH_MAX_SIZE));
- }
+ p = find_patch(0);
+ if (!p) {
+ return ret;
+ } else {
+ if (boot_cpu_data.microcode == p->patch_id)
+ return ret;
+
+ ret = UCODE_NEW;
}
-#endif
+
+ /* save BSP's matching patch for early load */
+ if (!save)
+ return ret;
+
+ memset(amd_ucode_patch, 0, PATCH_MAX_SIZE);
+ memcpy(amd_ucode_patch, p->data, min_t(u32, ksize(p->data), PATCH_MAX_SIZE));
+
return ret;
}
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 70ecbc8099c9..10c4fc2c91f8 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -517,7 +517,29 @@ static int check_online_cpus(void)
return -EINVAL;
}
-static atomic_t late_cpus;
+static atomic_t late_cpus_in;
+static atomic_t late_cpus_out;
+
+static int __wait_for_cpus(atomic_t *t, long long timeout)
+{
+ int all_cpus = num_online_cpus();
+
+ atomic_inc(t);
+
+ while (atomic_read(t) < all_cpus) {
+ if (timeout < SPINUNIT) {
+ pr_err("Timeout while waiting for CPUs rendezvous, remaining: %d\n",
+ all_cpus - atomic_read(t));
+ return 1;
+ }
+
+ ndelay(SPINUNIT);
+ timeout -= SPINUNIT;
+
+ touch_nmi_watchdog();
+ }
+ return 0;
+}
/*
* Returns:
@@ -527,30 +549,16 @@ static atomic_t late_cpus;
*/
static int __reload_late(void *info)
{
- unsigned int timeout = NSEC_PER_SEC;
- int all_cpus = num_online_cpus();
int cpu = smp_processor_id();
enum ucode_state err;
int ret = 0;
- atomic_dec(&late_cpus);
-
/*
* Wait for all CPUs to arrive. A load will not be attempted unless all
* CPUs show up.
* */
- while (atomic_read(&late_cpus)) {
- if (timeout < SPINUNIT) {
- pr_err("Timeout while waiting for CPUs rendezvous, remaining: %d\n",
- atomic_read(&late_cpus));
- return -1;
- }
-
- ndelay(SPINUNIT);
- timeout -= SPINUNIT;
-
- touch_nmi_watchdog();
- }
+ if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC))
+ return -1;
spin_lock(&update_lock);
apply_microcode_local(&err);
@@ -558,15 +566,22 @@ static int __reload_late(void *info)
if (err > UCODE_NFOUND) {
pr_warn("Error reloading microcode on CPU %d\n", cpu);
- ret = -1;
- } else if (err == UCODE_UPDATED) {
+ return -1;
+ /* siblings return UCODE_OK because their engine got updated already */
+ } else if (err == UCODE_UPDATED || err == UCODE_OK) {
ret = 1;
+ } else {
+ return ret;
}
- atomic_inc(&late_cpus);
-
- while (atomic_read(&late_cpus) != all_cpus)
- cpu_relax();
+ /*
+ * Increase the wait timeout to a safe value here since we're
+ * serializing the microcode update and that could take a while on a
+ * large number of CPUs. And that is fine as the *actual* timeout will
+ * be determined by the last CPU finished updating and thus cut short.
+ */
+ if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC * num_online_cpus()))
+ panic("Timeout during microcode update!\n");
return ret;
}
@@ -579,12 +594,11 @@ static int microcode_reload_late(void)
{
int ret;
- atomic_set(&late_cpus, num_online_cpus());
+ atomic_set(&late_cpus_in, 0);
+ atomic_set(&late_cpus_out, 0);
ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask);
- if (ret < 0)
- return ret;
- else if (ret > 0)
+ if (ret > 0)
microcode_check();
return ret;
@@ -607,7 +621,7 @@ static ssize_t reload_store(struct device *dev,
return size;
tmp_ret = microcode_ops->request_microcode_fw(bsp, &microcode_pdev->dev, true);
- if (tmp_ret != UCODE_OK)
+ if (tmp_ret != UCODE_NEW)
return size;
get_online_cpus();
@@ -691,10 +705,8 @@ static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
if (system_state != SYSTEM_RUNNING)
return UCODE_NFOUND;
- ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev,
- refresh_fw);
-
- if (ustate == UCODE_OK) {
+ ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev, refresh_fw);
+ if (ustate == UCODE_NEW) {
pr_debug("CPU%d updated upon init\n", cpu);
apply_microcode_on_target(cpu);
}
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 2aded9db1d42..32b8e5724f96 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -862,6 +862,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
unsigned int leftover = size;
unsigned int curr_mc_size = 0, new_mc_size = 0;
unsigned int csig, cpf;
+ enum ucode_state ret = UCODE_OK;
while (leftover) {
struct microcode_header_intel mc_header;
@@ -903,6 +904,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
new_mc = mc;
new_mc_size = mc_size;
mc = NULL; /* trigger new vmalloc */
+ ret = UCODE_NEW;
}
ucode_ptr += mc_size;
@@ -932,7 +934,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
cpu, new_rev, uci->cpu_sig.rev);
- return UCODE_OK;
+ return ret;
}
static int get_ucode_fw(void *to, const void *from, size_t n)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 56d99be3706a..50bee5fe1140 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -160,7 +160,6 @@ static const __initconst struct idt_data early_pf_idts[] = {
*/
static const __initconst struct idt_data dbg_idts[] = {
INTG(X86_TRAP_DB, debug),
- INTG(X86_TRAP_BP, int3),
};
#endif
@@ -183,7 +182,6 @@ gate_desc debug_idt_table[IDT_ENTRIES] __page_aligned_bss;
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),
ISTG(X86_TRAP_DF, double_fault, DOUBLEFAULT_STACK),
#ifdef CONFIG_X86_MCE
ISTG(X86_TRAP_MC, &machine_check, MCE_STACK),
diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
index 618285e475c6..ac7ea3a8242f 100644
--- a/arch/x86/kernel/pci-nommu.c
+++ b/arch/x86/kernel/pci-nommu.c
@@ -37,7 +37,6 @@ static dma_addr_t nommu_map_page(struct device *dev, struct page *page,
WARN_ON(size == 0);
if (!check_addr("map_single", dev, bus, size))
return NOMMU_MAPPING_ERROR;
- flush_write_buffers();
return bus;
}
@@ -72,25 +71,9 @@ static int nommu_map_sg(struct device *hwdev, struct scatterlist *sg,
return 0;
s->dma_length = s->length;
}
- flush_write_buffers();
return nents;
}
-static void nommu_sync_single_for_device(struct device *dev,
- dma_addr_t addr, size_t size,
- enum dma_data_direction dir)
-{
- flush_write_buffers();
-}
-
-
-static void nommu_sync_sg_for_device(struct device *dev,
- struct scatterlist *sg, int nelems,
- enum dma_data_direction dir)
-{
- flush_write_buffers();
-}
-
static int nommu_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return dma_addr == NOMMU_MAPPING_ERROR;
@@ -101,8 +84,6 @@ const struct dma_map_ops nommu_dma_ops = {
.free = dma_generic_free_coherent,
.map_sg = nommu_map_sg,
.map_page = nommu_map_page,
- .sync_single_for_device = nommu_sync_single_for_device,
- .sync_sg_for_device = nommu_sync_sg_for_device,
.is_phys = 1,
.mapping_error = nommu_mapping_error,
.dma_supported = x86_dma_supported,
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 3d9b2308e7fa..03f3d7695dac 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -577,7 +577,6 @@ do_general_protection(struct pt_regs *regs, long error_code)
}
NOKPROBE_SYMBOL(do_general_protection);
-/* May run on IST stack. */
dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
{
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -592,6 +591,13 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
if (poke_int3_handler(regs))
return;
+ /*
+ * Use ist_enter despite the fact that we don't use an IST stack.
+ * We can be called from a kprobe in non-CONTEXT_KERNEL kernel
+ * mode or even during context tracking state changes.
+ *
+ * This means that we can't schedule. That's okay.
+ */
ist_enter(regs);
RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
@@ -609,15 +615,10 @@ dotraplinkage void notrace do_int3(struct pt_regs *regs, long error_code)
SIGTRAP) == NOTIFY_STOP)
goto exit;
- /*
- * Let others (NMI) know that the debug stack is in use
- * as we may switch to the interrupt stack.
- */
- debug_stack_usage_inc();
cond_local_irq_enable(regs);
do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL);
cond_local_irq_disable(regs);
- debug_stack_usage_dec();
+
exit:
ist_exit(regs);
}
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index 5edb27f1a2c4..9d0b5af7db91 100644
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -727,7 +727,8 @@ void handle_vm86_fault(struct kernel_vm86_regs *regs, long error_code)
return;
check_vip:
- if (VEFLAGS & X86_EFLAGS_VIP) {
+ if ((VEFLAGS & (X86_EFLAGS_VIP | X86_EFLAGS_VIF)) ==
+ (X86_EFLAGS_VIP | X86_EFLAGS_VIF)) {
save_v86_state(regs, VM86_STI);
return;
}
generated by cgit (git 2.34.1) at 2024-06-07 14:24:41 +0000