diff options
Diffstat (limited to 'arch/powerpc/kernel/security.c')
-rw-r--r-- | arch/powerpc/kernel/security.c | 56 |
1 files changed, 37 insertions, 19 deletions
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c index f6f469fc4073..70568ccbd9fd 100644 --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -4,6 +4,7 @@ // // Copyright 2018, Michael Ellerman, IBM Corporation. +#include <linux/cpu.h> #include <linux/kernel.h> #include <linux/device.h> #include <linux/seq_buf.h> @@ -22,10 +23,14 @@ enum count_cache_flush_type { COUNT_CACHE_FLUSH_SW = 0x2, COUNT_CACHE_FLUSH_HW = 0x4, }; -static enum count_cache_flush_type count_cache_flush_type; +static enum count_cache_flush_type count_cache_flush_type = COUNT_CACHE_FLUSH_NONE; bool barrier_nospec_enabled; static bool no_nospec; +static bool btb_flush_enabled; +#ifdef CONFIG_PPC_FSL_BOOK3E +static bool no_spectrev2; +#endif static void enable_barrier_nospec(bool enable) { @@ -52,7 +57,7 @@ void setup_barrier_nospec(void) enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR); - if (!no_nospec) + if (!no_nospec && !cpu_mitigations_off()) enable_barrier_nospec(enable); } @@ -101,6 +106,23 @@ static __init int barrier_nospec_debugfs_init(void) device_initcall(barrier_nospec_debugfs_init); #endif /* CONFIG_DEBUG_FS */ +#ifdef CONFIG_PPC_FSL_BOOK3E +static int __init handle_nospectre_v2(char *p) +{ + no_spectrev2 = true; + + return 0; +} +early_param("nospectre_v2", handle_nospectre_v2); +void setup_spectre_v2(void) +{ + if (no_spectrev2 || cpu_mitigations_off()) + do_btb_flush_fixups(); + else + btb_flush_enabled = true; +} +#endif /* CONFIG_PPC_FSL_BOOK3E */ + #ifdef CONFIG_PPC_BOOK3S_64 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) { @@ -168,31 +190,27 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED); ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED); - if (bcs || ccd || count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) { - bool comma = false; + if (bcs || ccd) { seq_buf_printf(&s, "Mitigation: "); - if (bcs) { + if (bcs) seq_buf_printf(&s, "Indirect branch serialisation (kernel only)"); - comma = true; - } - - if (ccd) { - if (comma) - seq_buf_printf(&s, ", "); - seq_buf_printf(&s, "Indirect branch cache disabled"); - comma = true; - } - if (comma) + if (bcs && ccd) seq_buf_printf(&s, ", "); - seq_buf_printf(&s, "Software count cache flush"); + if (ccd) + seq_buf_printf(&s, "Indirect branch cache disabled"); + } else if (count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) { + seq_buf_printf(&s, "Mitigation: Software count cache flush"); if (count_cache_flush_type == COUNT_CACHE_FLUSH_HW) - seq_buf_printf(&s, "(hardware accelerated)"); - } else + seq_buf_printf(&s, " (hardware accelerated)"); + } else if (btb_flush_enabled) { + seq_buf_printf(&s, "Mitigation: Branch predictor state flush"); + } else { seq_buf_printf(&s, "Vulnerable"); + } seq_buf_printf(&s, "\n"); @@ -282,7 +300,7 @@ void setup_stf_barrier(void) stf_enabled_flush_types = type; - if (!no_stf_barrier) + if (!no_stf_barrier && !cpu_mitigations_off()) stf_barrier_enable(enable); } |