diff options
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/kernel/cpu/microcode/amd.c | 4 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/microcode/core.c | 36 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/microcode/intel.c | 5 |
3 files changed, 26 insertions, 19 deletions
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index a0e52bd00ecc..3f6b137ef4e6 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -567,7 +567,7 @@ int __init save_microcode_in_initrd_amd(unsigned int cpuid_1_eax) void reload_ucode_amd(void) { struct microcode_amd *mc; - u32 rev, dummy; + u32 rev, dummy __always_unused; mc = (struct microcode_amd *)amd_ucode_patch; @@ -673,7 +673,7 @@ static enum ucode_state apply_microcode_amd(int cpu) struct ucode_cpu_info *uci; struct ucode_patch *p; enum ucode_state ret; - u32 rev, dummy; + u32 rev, dummy __always_unused; BUG_ON(raw_smp_processor_id() != cpu); diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index cb0fdcaf1415..7019d4b2df0c 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -63,11 +63,6 @@ LIST_HEAD(microcode_cache); */ static DEFINE_MUTEX(microcode_mutex); -/* - * Serialize late loading so that CPUs get updated one-by-one. - */ -static DEFINE_RAW_SPINLOCK(update_lock); - struct ucode_cpu_info ucode_cpu_info[NR_CPUS]; struct cpu_info_ctx { @@ -566,11 +561,18 @@ static int __reload_late(void *info) if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC)) return -1; - raw_spin_lock(&update_lock); - apply_microcode_local(&err); - raw_spin_unlock(&update_lock); + /* + * On an SMT system, it suffices to load the microcode on one sibling of + * the core because the microcode engine is shared between the threads. + * Synchronization still needs to take place so that no concurrent + * loading attempts happen on multiple threads of an SMT core. See + * below. + */ + if (cpumask_first(topology_sibling_cpumask(cpu)) == cpu) + apply_microcode_local(&err); + else + goto wait_for_siblings; - /* siblings return UCODE_OK because their engine got updated already */ if (err > UCODE_NFOUND) { pr_warn("Error reloading microcode on CPU %d\n", cpu); ret = -1; @@ -578,14 +580,18 @@ static int __reload_late(void *info) ret = 1; } +wait_for_siblings: + if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC)) + panic("Timeout during microcode update!\n"); + /* - * 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. + * At least one thread has completed update on each core. + * For others, simply call the update to make sure the + * per-cpu cpuinfo can be updated with right microcode + * revision. */ - if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC * num_online_cpus())) - panic("Timeout during microcode update!\n"); + if (cpumask_first(topology_sibling_cpumask(cpu)) != cpu) + apply_microcode_local(&err); return ret; } diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index ce799cfe9434..6a99535d7f37 100644 --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -791,6 +791,7 @@ static enum ucode_state apply_microcode_intel(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; struct cpuinfo_x86 *c = &cpu_data(cpu); + bool bsp = c->cpu_index == boot_cpu_data.cpu_index; struct microcode_intel *mc; enum ucode_state ret; static int prev_rev; @@ -836,7 +837,7 @@ static enum ucode_state apply_microcode_intel(int cpu) return UCODE_ERROR; } - if (rev != prev_rev) { + if (bsp && rev != prev_rev) { pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n", rev, mc->hdr.date & 0xffff, @@ -852,7 +853,7 @@ out: c->microcode = rev; /* Update boot_cpu_data's revision too, if we're on the BSP: */ - if (c->cpu_index == boot_cpu_data.cpu_index) + if (bsp) boot_cpu_data.microcode = rev; return ret; |