diff options
| -rw-r--r-- | arch/x86/include/asm/pat.h | 1 | ||||
| -rw-r--r-- | arch/x86/mm/pat.c | 13 |
2 files changed, 13 insertions, 1 deletions
diff --git a/arch/x86/include/asm/pat.h b/arch/x86/include/asm/pat.h index 97ea55bc2b54..0ad356c066ef 100644 --- a/arch/x86/include/asm/pat.h +++ b/arch/x86/include/asm/pat.h @@ -5,6 +5,7 @@ #include <asm/pgtable_types.h> bool pat_enabled(void); +void pat_disable(const char *reason); extern void pat_init(void); void __init_cache_modes(u64); diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index b4663885308f..1cc1d37f1de7 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -40,11 +40,22 @@ static bool boot_cpu_done; static int __read_mostly __pat_enabled = IS_ENABLED(CONFIG_X86_PAT); +static void init_cache_modes(void); -static inline void pat_disable(const char *reason) +void pat_disable(const char *reason) { + if (!__pat_enabled) + return; + + if (boot_cpu_done) { + WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n"); + return; + } + __pat_enabled = 0; pr_info("x86/PAT: %s\n", reason); + + init_cache_modes(); } static int __init nopat(char *str) |