diff options
| -rw-r--r-- | arch/arm64/include/asm/alternative.h | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/alternative.c | 21 | ||||
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 2 |
3 files changed, 19 insertions, 7 deletions
diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h index 4b650ec1d7dd..9806a2357e70 100644 --- a/arch/arm64/include/asm/alternative.h +++ b/arch/arm64/include/asm/alternative.h @@ -14,8 +14,6 @@ #include <linux/stddef.h> #include <linux/stringify.h> -extern int alternatives_applied; - struct alt_instr { s32 orig_offset; /* offset to original instruction */ s32 alt_offset; /* offset to replacement instruction */ @@ -28,6 +26,7 @@ typedef void (*alternative_cb_t)(struct alt_instr *alt, __le32 *origptr, __le32 *updptr, int nr_inst); void __init apply_alternatives_all(void); +bool alternative_is_applied(u16 cpufeature); #ifdef CONFIG_MODULES void apply_alternatives_module(void *start, size_t length); diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index b5d603992d40..c947d2246017 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -32,13 +32,23 @@ #define ALT_ORIG_PTR(a) __ALT_PTR(a, orig_offset) #define ALT_REPL_PTR(a) __ALT_PTR(a, alt_offset) -int alternatives_applied; +static int all_alternatives_applied; + +static DECLARE_BITMAP(applied_alternatives, ARM64_NCAPS); struct alt_region { struct alt_instr *begin; struct alt_instr *end; }; +bool alternative_is_applied(u16 cpufeature) +{ + if (WARN_ON(cpufeature >= ARM64_NCAPS)) + return false; + + return test_bit(cpufeature, applied_alternatives); +} + /* * Check if the target PC is within an alternative block. */ @@ -192,6 +202,9 @@ static void __apply_alternatives(void *alt_region, bool is_module) dsb(ish); __flush_icache_all(); isb(); + + /* We applied all that was available */ + bitmap_copy(applied_alternatives, cpu_hwcaps, ARM64_NCAPS); } } @@ -208,14 +221,14 @@ static int __apply_alternatives_multi_stop(void *unused) /* We always have a CPU 0 at this point (__init) */ if (smp_processor_id()) { - while (!READ_ONCE(alternatives_applied)) + while (!READ_ONCE(all_alternatives_applied)) cpu_relax(); isb(); } else { - BUG_ON(alternatives_applied); + BUG_ON(all_alternatives_applied); __apply_alternatives(®ion, false); /* Barriers provided by the cache flushing */ - WRITE_ONCE(alternatives_applied, 1); + WRITE_ONCE(all_alternatives_applied, 1); } return 0; diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 6f56e0ab63a1..d607ea33228c 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1118,7 +1118,7 @@ static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused) * that, freshly-onlined CPUs will set tpidr_el2, so we don't need to * do anything here. */ - if (!alternatives_applied) + if (!alternative_is_applied(ARM64_HAS_VIRT_HOST_EXTN)) write_sysreg(read_sysreg(tpidr_el1), tpidr_el2); } #endif |