diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 0d289240b6ca110ab961a280ddd20fc1c567f2a4..775cac3c02bb0a31facb970e16feef83f86c6632 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -111,6 +111,7 @@
#include <linux/kernel.h>
extern unsigned int processor_id;
+struct proc_info_list *lookup_processor(u32 midr);
#ifdef CONFIG_CPU_CP15
#define read_cpuid(reg) \
diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h
index e25f4392e1b2868446de858701d408aaaee26eab..e1b6f280ab088fb0b8ac59b6ceb3543606c97e01 100644
--- a/arch/arm/include/asm/proc-fns.h
+++ b/arch/arm/include/asm/proc-fns.h
@@ -23,7 +23,7 @@ struct mm_struct;
/*
* Don't change this structure - ASM code relies on it.
*/
-extern struct processor {
+struct processor {
/* MISC
* get data abort address/flags
*/
@@ -79,9 +79,13 @@ extern struct processor {
unsigned int suspend_size;
void (*do_suspend)(void *);
void (*do_resume)(void *);
-} processor;
+};
#ifndef MULTI_CPU
+static inline void init_proc_vtable(const struct processor *p)
+{
+}
+
extern void cpu_proc_init(void);
extern void cpu_proc_fin(void);
extern int cpu_do_idle(void);
@@ -98,17 +102,50 @@ extern void cpu_reset(unsigned long addr, bool hvc) __attribute__((noreturn));
extern void cpu_do_suspend(void *);
extern void cpu_do_resume(void *);
#else
-#define cpu_proc_init processor._proc_init
-#define cpu_proc_fin processor._proc_fin
-#define cpu_reset processor.reset
-#define cpu_do_idle processor._do_idle
-#define cpu_dcache_clean_area processor.dcache_clean_area
-#define cpu_set_pte_ext processor.set_pte_ext
-#define cpu_do_switch_mm processor.switch_mm
-/* These three are private to arch/arm/kernel/suspend.c */
-#define cpu_do_suspend processor.do_suspend
-#define cpu_do_resume processor.do_resume
+extern struct processor processor;
+#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
+#include <linux/smp.h>
+/*
+ * This can't be a per-cpu variable because we need to access it before
+ * per-cpu has been initialised. We have a couple of functions that are
+ * called in a pre-emptible context, and so can't use smp_processor_id()
+ * there, hence PROC_TABLE(). We insist in init_proc_vtable() that the
+ * function pointers for these are identical across all CPUs.
+ */
+extern struct processor *cpu_vtable[];
+#define PROC_VTABLE(f) cpu_vtable[smp_processor_id()]->f
+#define PROC_TABLE(f) cpu_vtable[0]->f
+static inline void init_proc_vtable(const struct processor *p)
+{
+ unsigned int cpu = smp_processor_id();
+ *cpu_vtable[cpu] = *p;
+ WARN_ON_ONCE(cpu_vtable[cpu]->dcache_clean_area !=
+ cpu_vtable[0]->dcache_clean_area);
+ WARN_ON_ONCE(cpu_vtable[cpu]->set_pte_ext !=
+ cpu_vtable[0]->set_pte_ext);
+}
+#else
+#define PROC_VTABLE(f) processor.f
+#define PROC_TABLE(f) processor.f
+static inline void init_proc_vtable(const struct processor *p)
+{
+ processor = *p;
+}
+#endif
+
+#define cpu_proc_init PROC_VTABLE(_proc_init)
+#define cpu_check_bugs PROC_VTABLE(check_bugs)
+#define cpu_proc_fin PROC_VTABLE(_proc_fin)
+#define cpu_reset PROC_VTABLE(reset)
+#define cpu_do_idle PROC_VTABLE(_do_idle)
+#define cpu_dcache_clean_area PROC_TABLE(dcache_clean_area)
+#define cpu_set_pte_ext PROC_TABLE(set_pte_ext)
+#define cpu_do_switch_mm PROC_VTABLE(switch_mm)
+
+/* These two are private to arch/arm/kernel/suspend.c */
+#define cpu_do_suspend PROC_VTABLE(do_suspend)
+#define cpu_do_resume PROC_VTABLE(do_resume)
#endif
extern void cpu_resume(void);
diff --git a/arch/arm/kernel/bugs.c b/arch/arm/kernel/bugs.c
index 7be5113101915cd81a5558f45238041138fb5a58..d41d3598e5e541115c08f9b81b26fd187a7fe7af 100644
--- a/arch/arm/kernel/bugs.c
+++ b/arch/arm/kernel/bugs.c
@@ -6,8 +6,8 @@
void check_other_bugs(void)
{
#ifdef MULTI_CPU
- if (processor.check_bugs)
- processor.check_bugs();
+ if (cpu_check_bugs)
+ cpu_check_bugs();
#endif
}
diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S
index 6e0375e7db055bc82cf0674b37b74646e2d64ff0..997b02302c3145f5ac380ae18823eba50d916ac7 100644
--- a/arch/arm/kernel/head-common.S
+++ b/arch/arm/kernel/head-common.S
@@ -145,6 +145,9 @@ __mmap_switched_data:
#endif
.size __mmap_switched_data, . - __mmap_switched_data
+ __FINIT
+ .text
+
/*
* This provides a C-API version of __lookup_processor_type
*/
@@ -156,9 +159,6 @@ ENTRY(lookup_processor_type)
ldmfd sp!, {r4 - r6, r9, pc}
ENDPROC(lookup_processor_type)
- __FINIT
- .text
-
/*
* Read processor ID register (CP#15, CR0), and look up in the linker-built
* supported processor list. Note that we can't use the absolute addresses
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index ac7e08886863cfa74855e5b91c4f436e85da1e0a..375b13f7e780663eddb3f04e632751064a6b5bfd 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -114,6 +114,11 @@ EXPORT_SYMBOL(elf_hwcap2);
#ifdef MULTI_CPU
struct processor processor __ro_after_init;
+#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
+struct processor *cpu_vtable[NR_CPUS] = {
+ [0] = &processor,
+};
+#endif
#endif
#ifdef MULTI_TLB
struct cpu_tlb_fns cpu_tlb __ro_after_init;
@@ -666,28 +671,33 @@ static void __init smp_build_mpidr_hash(void)
}
#endif
-static void __init setup_processor(void)
+/*
+ * locate processor in the list of supported processor types. The linker
+ * builds this table for us from the entries in arch/arm/mm/proc-*.S
+ */
+struct proc_info_list *lookup_processor(u32 midr)
{
- struct proc_info_list *list;
+ struct proc_info_list *list = lookup_processor_type(midr);
- /*
- * locate processor in the list of supported processor
- * types. The linker builds this table for us from the
- * entries in arch/arm/mm/proc-*.S
- */
- list = lookup_processor_type(read_cpuid_id());
if (!list) {
- pr_err("CPU configuration botched (ID %08x), unable to continue.\n",
- read_cpuid_id());
- while (1);
+ pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n",
+ smp_processor_id(), midr);
+ while (1)
+ /* can't use cpu_relax() here as it may require MMU setup */;
}
+ return list;
+}
+
+static void __init setup_processor(void)
+{
+ unsigned int midr = read_cpuid_id();
+ struct proc_info_list *list = lookup_processor(midr);
+
cpu_name = list->cpu_name;
__cpu_architecture = __get_cpu_architecture();
-#ifdef MULTI_CPU
- processor = *list->proc;
-#endif
+ init_proc_vtable(list->proc);
#ifdef MULTI_TLB
cpu_tlb = *list->tlb;
#endif
@@ -699,7 +709,7 @@ static void __init setup_processor(void)
#endif
pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n",
- cpu_name, read_cpuid_id(), read_cpuid_id() & 15,
+ list->cpu_name, midr, midr & 15,
proc_arch[cpu_architecture()], get_cr());
snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c",
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 0978282d5fc27a7c4a5e6b0e274da8bfc4c14c8d..12a6172263c0b057a94f2041accf581088374fb0 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -42,6 +42,7 @@
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
+#include <asm/procinfo.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/tlbflush.h>
@@ -102,6 +103,30 @@ static unsigned long get_arch_pgd(pgd_t *pgd)
#endif
}
+#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
+static int secondary_biglittle_prepare(unsigned int cpu)
+{
+ if (!cpu_vtable[cpu])
+ cpu_vtable[cpu] = kzalloc(sizeof(*cpu_vtable[cpu]), GFP_KERNEL);
+
+ return cpu_vtable[cpu] ? 0 : -ENOMEM;
+}
+
+static void secondary_biglittle_init(void)
+{
+ init_proc_vtable(lookup_processor(read_cpuid_id())->proc);
+}
+#else
+static int secondary_biglittle_prepare(unsigned int cpu)
+{
+ return 0;
+}
+
+static void secondary_biglittle_init(void)
+{
+}
+#endif
+
int __cpu_up(unsigned int cpu, struct task_struct *idle)
{
int ret;
@@ -109,6 +134,10 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
if (!smp_ops.smp_boot_secondary)
return -ENOSYS;
+ ret = secondary_biglittle_prepare(cpu);
+ if (ret)
+ return ret;
+
/*
* We need to tell the secondary core where to find
* its stack and the page tables.
@@ -359,6 +388,8 @@ asmlinkage void secondary_start_kernel(void)
struct mm_struct *mm = &init_mm;
unsigned int cpu;
+ secondary_biglittle_init();
+
/*
* The identity mapping is uncached (strongly ordered), so
* switch away from it before attempting any exclusive accesses.
diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c
index 5544b82a2e7a553d015e23d77a9017682dd91f11..9a07916af8dd27dd021781c06451340ce6d03032 100644
--- a/arch/arm/mm/proc-v7-bugs.c
+++ b/arch/arm/mm/proc-v7-bugs.c
@@ -52,8 +52,6 @@ static void cpu_v7_spectre_init(void)
case ARM_CPU_PART_CORTEX_A17:
case ARM_CPU_PART_CORTEX_A73:
case ARM_CPU_PART_CORTEX_A75:
- if (processor.switch_mm != cpu_v7_bpiall_switch_mm)
- goto bl_error;
per_cpu(harden_branch_predictor_fn, cpu) =
harden_branch_predictor_bpiall;
spectre_v2_method = "BPIALL";
@@ -61,8 +59,6 @@ static void cpu_v7_spectre_init(void)
case ARM_CPU_PART_CORTEX_A15:
case ARM_CPU_PART_BRAHMA_B15:
- if (processor.switch_mm != cpu_v7_iciallu_switch_mm)
- goto bl_error;
per_cpu(harden_branch_predictor_fn, cpu) =
harden_branch_predictor_iciallu;
spectre_v2_method = "ICIALLU";
@@ -88,11 +84,9 @@ static void cpu_v7_spectre_init(void)
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if ((int)res.a0 != 0)
break;
- if (processor.switch_mm != cpu_v7_hvc_switch_mm && cpu)
- goto bl_error;
per_cpu(harden_branch_predictor_fn, cpu) =
call_hvc_arch_workaround_1;
- processor.switch_mm = cpu_v7_hvc_switch_mm;
+ cpu_do_switch_mm = cpu_v7_hvc_switch_mm;
spectre_v2_method = "hypervisor";
break;
@@ -101,11 +95,9 @@ static void cpu_v7_spectre_init(void)
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if ((int)res.a0 != 0)
break;
- if (processor.switch_mm != cpu_v7_smc_switch_mm && cpu)
- goto bl_error;
per_cpu(harden_branch_predictor_fn, cpu) =
call_smc_arch_workaround_1;
- processor.switch_mm = cpu_v7_smc_switch_mm;
+ cpu_do_switch_mm = cpu_v7_smc_switch_mm;
spectre_v2_method = "firmware";
break;
@@ -119,11 +111,6 @@ static void cpu_v7_spectre_init(void)
if (spectre_v2_method)
pr_info("CPU%u: Spectre v2: using %s workaround\n",
smp_processor_id(), spectre_v2_method);
- return;
-
-bl_error:
- pr_err("CPU%u: Spectre v2: incorrect context switching function, system vulnerable\n",
- cpu);
}
#else
static void cpu_v7_spectre_init(void)