diff options
Diffstat (limited to 'arch/powerpc/kernel/setup_64.c')
-rw-r--r-- | arch/powerpc/kernel/setup_64.c | 48 |
1 files changed, 18 insertions, 30 deletions
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 9527a4c6cbc2..0618aa61b26a 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -822,9 +822,6 @@ static void do_nothing(void *unused) void rfi_flush_enable(bool enable) { - if (rfi_flush == enable) - return; - if (enable) { do_rfi_flush_fixups(enabled_flush_types); on_each_cpu(do_nothing, NULL, 1); @@ -834,11 +831,15 @@ void rfi_flush_enable(bool enable) rfi_flush = enable; } -static void init_fallback_flush(void) +static void __ref init_fallback_flush(void) { u64 l1d_size, limit; int cpu; + /* Only allocate the fallback flush area once (at boot time). */ + if (l1d_flush_fallback_area) + return; + l1d_size = ppc64_caches.l1d.size; limit = min(safe_stack_limit(), ppc64_rma_size); @@ -851,34 +852,23 @@ static void init_fallback_flush(void) memset(l1d_flush_fallback_area, 0, l1d_size * 2); for_each_possible_cpu(cpu) { - /* - * The fallback flush is currently coded for 8-way - * associativity. Different associativity is possible, but it - * will be treated as 8-way and may not evict the lines as - * effectively. - * - * 128 byte lines are mandatory. - */ - u64 c = l1d_size / 8; - paca[cpu].rfi_flush_fallback_area = l1d_flush_fallback_area; - paca[cpu].l1d_flush_congruence = c; - paca[cpu].l1d_flush_sets = c / 128; + paca[cpu].l1d_flush_size = l1d_size; } } -void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) +void setup_rfi_flush(enum l1d_flush_type types, bool enable) { if (types & L1D_FLUSH_FALLBACK) { - pr_info("rfi-flush: Using fallback displacement flush\n"); + pr_info("rfi-flush: fallback displacement flush available\n"); init_fallback_flush(); } if (types & L1D_FLUSH_ORI) - pr_info("rfi-flush: Using ori type flush\n"); + pr_info("rfi-flush: ori type flush available\n"); if (types & L1D_FLUSH_MTTRIG) - pr_info("rfi-flush: Using mttrig type flush\n"); + pr_info("rfi-flush: mttrig type flush available\n"); enabled_flush_types = types; @@ -889,13 +879,19 @@ void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) #ifdef CONFIG_DEBUG_FS static int rfi_flush_set(void *data, u64 val) { + bool enable; + if (val == 1) - rfi_flush_enable(true); + enable = true; else if (val == 0) - rfi_flush_enable(false); + enable = false; else return -EINVAL; + /* Only do anything if we're changing state */ + if (enable != rfi_flush) + rfi_flush_enable(enable); + return 0; } @@ -914,12 +910,4 @@ static __init int rfi_flush_debugfs_init(void) } device_initcall(rfi_flush_debugfs_init); #endif - -ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) -{ - if (rfi_flush) - return sprintf(buf, "Mitigation: RFI Flush\n"); - - return sprintf(buf, "Vulnerable\n"); -} #endif /* CONFIG_PPC_BOOK3S_64 */ |