diff options
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/powerpc/kernel/asm-offsets.c | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/cpu_setup_power.S | 6 | ||||
-rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 1 | ||||
-rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 95 | ||||
-rw-r--r-- | arch/powerpc/kernel/idle_book3s.S | 2 | ||||
-rw-r--r-- | arch/powerpc/kernel/security.c | 237 | ||||
-rw-r--r-- | arch/powerpc/kernel/setup-common.c | 11 | ||||
-rw-r--r-- | arch/powerpc/kernel/setup_64.c | 48 | ||||
-rw-r--r-- | arch/powerpc/kernel/traps.c | 47 | ||||
-rw-r--r-- | arch/powerpc/kernel/vmlinux.lds.S | 14 |
11 files changed, 363 insertions, 103 deletions
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 6c6cce937dd8..1479c61e29c5 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -42,7 +42,7 @@ obj-$(CONFIG_VDSO32) += vdso32/ obj-$(CONFIG_PPC_WATCHDOG) += watchdog.o obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_ppc970.o cpu_setup_pa6t.o -obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_power.o +obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_power.o security.o obj-$(CONFIG_PPC_BOOK3S_64) += mce.o mce_power.o obj-$(CONFIG_PPC_BOOK3E_64) += exceptions-64e.o idle_book3e.o obj-$(CONFIG_PPC64) += vdso64/ diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 90c2d96aff6f..a2cb40098d7c 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -240,8 +240,7 @@ int main(void) OFFSET(PACA_IN_NMI, paca_struct, in_nmi); OFFSET(PACA_RFI_FLUSH_FALLBACK_AREA, paca_struct, rfi_flush_fallback_area); OFFSET(PACA_EXRFI, paca_struct, exrfi); - OFFSET(PACA_L1D_FLUSH_CONGRUENCE, paca_struct, l1d_flush_congruence); - OFFSET(PACA_L1D_FLUSH_SETS, paca_struct, l1d_flush_sets); + OFFSET(PACA_L1D_FLUSH_SIZE, paca_struct, l1d_flush_size); #endif OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id); diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S index 679bbe714e85..9daede99c131 100644 --- a/arch/powerpc/kernel/cpu_setup_power.S +++ b/arch/powerpc/kernel/cpu_setup_power.S @@ -28,6 +28,7 @@ _GLOBAL(__setup_cpu_power7) beqlr li r0,0 mtspr SPRN_LPID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR li r4,(LPCR_LPES1 >> LPCR_LPES_SH) bl __init_LPCR_ISA206 @@ -42,6 +43,7 @@ _GLOBAL(__restore_cpu_power7) beqlr li r0,0 mtspr SPRN_LPID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR li r4,(LPCR_LPES1 >> LPCR_LPES_SH) bl __init_LPCR_ISA206 @@ -59,6 +61,7 @@ _GLOBAL(__setup_cpu_power8) beqlr li r0,0 mtspr SPRN_LPID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR ori r3, r3, LPCR_PECEDH li r4,0 /* LPES = 0 */ @@ -81,6 +84,7 @@ _GLOBAL(__restore_cpu_power8) beqlr li r0,0 mtspr SPRN_LPID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR ori r3, r3, LPCR_PECEDH li r4,0 /* LPES = 0 */ @@ -103,6 +107,7 @@ _GLOBAL(__setup_cpu_power9) mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 mtspr SPRN_PID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC) or r3, r3, r4 @@ -128,6 +133,7 @@ _GLOBAL(__restore_cpu_power9) mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 mtspr SPRN_PID,r0 + mtspr SPRN_PCR,r0 mfspr r3,SPRN_LPCR LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC) or r3, r3, r4 diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index f047ae1b6271..2dba206b065a 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -137,6 +137,7 @@ static void __restore_cpu_cpufeatures(void) if (hv_mode) { mtspr(SPRN_LPID, 0); mtspr(SPRN_HFSCR, system_registers.hfscr); + mtspr(SPRN_PCR, 0); } mtspr(SPRN_FSCR, system_registers.fscr); diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index f9ca4bb3d48e..c09f0a6f8495 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -825,7 +825,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM) #endif -EXC_REAL_MASKABLE(decrementer, 0x900, 0x80) +EXC_REAL_OOL_MASKABLE(decrementer, 0x900, 0x80) EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x80, 0x900) TRAMP_KVM(PACA_EXGEN, 0x900) EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt) @@ -901,6 +901,7 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) mtctr r13; \ GET_PACA(r13); \ std r10,PACA_EXGEN+EX_R10(r13); \ + INTERRUPT_TO_KERNEL; \ KVMTEST_PR(0xc00); /* uses r10, branch to do_kvm_0xc00_system_call */ \ HMT_MEDIUM; \ mfctr r9; @@ -909,7 +910,8 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) #define SYSCALL_KVMTEST \ HMT_MEDIUM; \ mr r9,r13; \ - GET_PACA(r13); + GET_PACA(r13); \ + INTERRUPT_TO_KERNEL; #endif #define LOAD_SYSCALL_HANDLER(reg) \ @@ -1434,45 +1436,56 @@ masked_##_H##interrupt: \ b .; \ MASKED_DEC_HANDLER(_H) +TRAMP_REAL_BEGIN(stf_barrier_fallback) + std r9,PACA_EXRFI+EX_R9(r13) + std r10,PACA_EXRFI+EX_R10(r13) + sync + ld r9,PACA_EXRFI+EX_R9(r13) + ld r10,PACA_EXRFI+EX_R10(r13) + ori 31,31,0 + .rept 14 + b 1f +1: + .endr + blr + TRAMP_REAL_BEGIN(rfi_flush_fallback) SET_SCRATCH0(r13); GET_PACA(r13); std r9,PACA_EXRFI+EX_R9(r13) std r10,PACA_EXRFI+EX_R10(r13) std r11,PACA_EXRFI+EX_R11(r13) - std r12,PACA_EXRFI+EX_R12(r13) - std r8,PACA_EXRFI+EX_R13(r13) mfctr r9 ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13) - ld r11,PACA_L1D_FLUSH_SETS(r13) - ld r12,PACA_L1D_FLUSH_CONGRUENCE(r13) - /* - * The load adresses are at staggered offsets within cachelines, - * which suits some pipelines better (on others it should not - * hurt). - */ - addi r12,r12,8 + ld r11,PACA_L1D_FLUSH_SIZE(r13) + srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */ mtctr r11 DCBT_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */ /* order ld/st prior to dcbt stop all streams with flushing */ sync -1: li r8,0 - .rept 8 /* 8-way set associative */ - ldx r11,r10,r8 - add r8,r8,r12 - xor r11,r11,r11 // Ensure r11 is 0 even if fallback area is not - add r8,r8,r11 // Add 0, this creates a dependency on the ldx - .endr - addi r10,r10,128 /* 128 byte cache line */ + + /* + * The load adresses are at staggered offsets within cachelines, + * which suits some pipelines better (on others it should not + * hurt). + */ +1: + ld r11,(0x80 + 8)*0(r10) + ld r11,(0x80 + 8)*1(r10) + ld r11,(0x80 + 8)*2(r10) + ld r11,(0x80 + 8)*3(r10) + ld r11,(0x80 + 8)*4(r10) + ld r11,(0x80 + 8)*5(r10) + ld r11,(0x80 + 8)*6(r10) + ld r11,(0x80 + 8)*7(r10) + addi r10,r10,0x80*8 bdnz 1b mtctr r9 ld r9,PACA_EXRFI+EX_R9(r13) ld r10,PACA_EXRFI+EX_R10(r13) ld r11,PACA_EXRFI+EX_R11(r13) - ld r12,PACA_EXRFI+EX_R12(r13) - ld r8,PACA_EXRFI+EX_R13(r13) GET_SCRATCH0(r13); rfid @@ -1482,39 +1495,37 @@ TRAMP_REAL_BEGIN(hrfi_flush_fallback) std r9,PACA_EXRFI+EX_R9(r13) std r10,PACA_EXRFI+EX_R10(r13) std r11,PACA_EXRFI+EX_R11(r13) - std r12,PACA_EXRFI+EX_R12(r13) - std r8,PACA_EXRFI+EX_R13(r13) mfctr r9 ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13) - ld r11,PACA_L1D_FLUSH_SETS(r13) - ld r12,PACA_L1D_FLUSH_CONGRUENCE(r13) - /* - * The load adresses are at staggered offsets within cachelines, - * which suits some pipelines better (on others it should not - * hurt). - */ - addi r12,r12,8 + ld r11,PACA_L1D_FLUSH_SIZE(r13) + srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */ mtctr r11 DCBT_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */ /* order ld/st prior to dcbt stop all streams with flushing */ sync -1: li r8,0 - .rept 8 /* 8-way set associative */ - ldx r11,r10,r8 - add r8,r8,r12 - xor r11,r11,r11 // Ensure r11 is 0 even if fallback area is not - add r8,r8,r11 // Add 0, this creates a dependency on the ldx - .endr - addi r10,r10,128 /* 128 byte cache line */ + + /* + * The load adresses are at staggered offsets within cachelines, + * which suits some pipelines better (on others it should not + * hurt). + */ +1: + ld r11,(0x80 + 8)*0(r10) + ld r11,(0x80 + 8)*1(r10) + ld r11,(0x80 + 8)*2(r10) + ld r11,(0x80 + 8)*3(r10) + ld r11,(0x80 + 8)*4(r10) + ld r11,(0x80 + 8)*5(r10) + ld r11,(0x80 + 8)*6(r10) + ld r11,(0x80 + 8)*7(r10) + addi r10,r10,0x80*8 bdnz 1b mtctr r9 ld r9,PACA_EXRFI+EX_R9(r13) ld r10,PACA_EXRFI+EX_R10(r13) ld r11,PACA_EXRFI+EX_R11(r13) - ld r12,PACA_EXRFI+EX_R12(r13) - ld r8,PACA_EXRFI+EX_R13(r13) GET_SCRATCH0(r13); hrfid diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 1125c9be9e06..e35cebd45c35 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -838,6 +838,8 @@ BEGIN_FTR_SECTION mtspr SPRN_PTCR,r4 ld r4,_RPR(r1) mtspr SPRN_RPR,r4 + ld r4,_AMOR(r1) + mtspr SPRN_AMOR,r4 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) ld r4,_TSCR(r1) diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c new file mode 100644 index 000000000000..b98a722da915 --- /dev/null +++ b/arch/powerpc/kernel/security.c @@ -0,0 +1,237 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Security related flags and so on. +// +// Copyright 2018, Michael Ellerman, IBM Corporation. + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/seq_buf.h> + +#include <asm/debugfs.h> +#include <asm/security_features.h> + + +unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; + +ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) +{ + bool thread_priv; + + thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV); + + if (rfi_flush || thread_priv) { + struct seq_buf s; + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + seq_buf_printf(&s, "Mitigation: "); + + if (rfi_flush) + seq_buf_printf(&s, "RFI Flush"); + + if (rfi_flush && thread_priv) + seq_buf_printf(&s, ", "); + + if (thread_priv) + seq_buf_printf(&s, "L1D private per thread"); + + seq_buf_printf(&s, "\n"); + + return s.len; + } + + if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && + !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)) + return sprintf(buf, "Not affected\n"); + + return sprintf(buf, "Vulnerable\n"); +} + +ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf) +{ + if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) + return sprintf(buf, "Not affected\n"); + + return sprintf(buf, "Vulnerable\n"); +} + +ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf) +{ + bool bcs, ccd, ori; + struct seq_buf s; + + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED); + ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED); + ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31); + + if (bcs || ccd) { + seq_buf_printf(&s, "Mitigation: "); + + if (bcs) + seq_buf_printf(&s, "Indirect branch serialisation (kernel only)"); + + if (bcs && ccd) + seq_buf_printf(&s, ", "); + + if (ccd) + seq_buf_printf(&s, "Indirect branch cache disabled"); + } else + seq_buf_printf(&s, "Vulnerable"); + + if (ori) + seq_buf_printf(&s, ", ori31 speculation barrier enabled"); + + seq_buf_printf(&s, "\n"); + + return s.len; +} + +/* + * Store-forwarding barrier support. + */ + +static enum stf_barrier_type stf_enabled_flush_types; +static bool no_stf_barrier; +bool stf_barrier; + +static int __init handle_no_stf_barrier(char *p) +{ + pr_info("stf-barrier: disabled on command line."); + no_stf_barrier = true; + return 0; +} + +early_param("no_stf_barrier", handle_no_stf_barrier); + +/* This is the generic flag used by other architectures */ +static int __init handle_ssbd(char *p) +{ + if (!p || strncmp(p, "auto", 5) == 0 || strncmp(p, "on", 2) == 0 ) { + /* Until firmware tells us, we have the barrier with auto */ + return 0; + } else if (strncmp(p, "off", 3) == 0) { + handle_no_stf_barrier(NULL); + return 0; + } else + return 1; + + return 0; +} +early_param("spec_store_bypass_disable", handle_ssbd); + +/* This is the generic flag used by other architectures */ +static int __init handle_no_ssbd(char *p) +{ + handle_no_stf_barrier(NULL); + return 0; +} +early_param("nospec_store_bypass_disable", handle_no_ssbd); + +static void stf_barrier_enable(bool enable) +{ + if (enable) + do_stf_barrier_fixups(stf_enabled_flush_types); + else + do_stf_barrier_fixups(STF_BARRIER_NONE); + + stf_barrier = enable; +} + +void setup_stf_barrier(void) +{ + enum stf_barrier_type type; + bool enable, hv; + + hv = cpu_has_feature(CPU_FTR_HVMODE); + + /* Default to fallback in case fw-features are not available */ + if (cpu_has_feature(CPU_FTR_ARCH_300)) + type = STF_BARRIER_EIEIO; + else if (cpu_has_feature(CPU_FTR_ARCH_207S)) + type = STF_BARRIER_SYNC_ORI; + else if (cpu_has_feature(CPU_FTR_ARCH_206)) + type = STF_BARRIER_FALLBACK; + else + type = STF_BARRIER_NONE; + + enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && + (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || + (security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && hv)); + + if (type == STF_BARRIER_FALLBACK) { + pr_info("stf-barrier: fallback barrier available\n"); + } else if (type == STF_BARRIER_SYNC_ORI) { + pr_info("stf-barrier: hwsync barrier available\n"); + } else if (type == STF_BARRIER_EIEIO) { + pr_info("stf-barrier: eieio barrier available\n"); + } + + stf_enabled_flush_types = type; + + if (!no_stf_barrier) + stf_barrier_enable(enable); +} + +ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf) +{ + if (stf_barrier && stf_enabled_flush_types != STF_BARRIER_NONE) { + const char *type; + switch (stf_enabled_flush_types) { + case STF_BARRIER_EIEIO: + type = "eieio"; + break; + case STF_BARRIER_SYNC_ORI: + type = "hwsync"; + break; + case STF_BARRIER_FALLBACK: + type = "fallback"; + break; + default: + type = "unknown"; + } + return sprintf(buf, "Mitigation: Kernel entry/exit barrier (%s)\n", type); + } + + if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && + !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)) + return sprintf(buf, "Not affected\n"); + + return sprintf(buf, "Vulnerable\n"); +} + +#ifdef CONFIG_DEBUG_FS +static int stf_barrier_set(void *data, u64 val) +{ + bool enable; + + if (val == 1) + enable = true; + else if (val == 0) + enable = false; + else + return -EINVAL; + + /* Only do anything if we're changing state */ + if (enable != stf_barrier) + stf_barrier_enable(enable); + + return 0; +} + +static int stf_barrier_get(void *data, u64 *val) +{ + *val = stf_barrier ? 1 : 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_stf_barrier, stf_barrier_get, stf_barrier_set, "%llu\n"); + +static __init int stf_barrier_debugfs_init(void) +{ + debugfs_create_file("stf_barrier", 0600, powerpc_debugfs_root, NULL, &fops_stf_barrier); + return 0; +} +device_initcall(stf_barrier_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 90bc20efb4c7..b4fcb54b9686 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -242,14 +242,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) unsigned short maj; unsigned short min; - /* We only show online cpus: disable preempt (overzealous, I - * knew) to prevent cpu going down. */ - preempt_disable(); - if (!cpu_online(cpu_id)) { - preempt_enable(); - return 0; - } - #ifdef CONFIG_SMP pvr = per_cpu(cpu_pvr, cpu_id); #else @@ -358,9 +350,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) #ifdef CONFIG_SMP seq_printf(m, "\n"); #endif - - preempt_enable(); - /* If this is the last cpu, print the summary */ if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids) show_cpuinfo_summary(m); 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 */ diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index d17007451f62..ac2e5e56a9f0 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -182,6 +182,12 @@ static void oops_end(unsigned long flags, struct pt_regs *regs, } raw_local_irq_restore(flags); + /* + * system_reset_excption handles debugger, crash dump, panic, for 0x100 + */ + if (TRAP(regs) == 0x100) + return; + crash_fadump(regs, "die oops"); if (kexec_should_crash(current)) @@ -246,8 +252,13 @@ void die(const char *str, struct pt_regs *regs, long err) { unsigned long flags; - if (debugger(regs)) - return; + /* + * system_reset_excption handles debugger, crash dump, panic, for 0x100 + */ + if (TRAP(regs) != 0x100) { + if (debugger(regs)) + return; + } flags = oops_begin(regs); if (__die(str, regs, err)) @@ -1379,6 +1390,22 @@ void facility_unavailable_exception(struct pt_regs *regs) value = mfspr(SPRN_FSCR); status = value >> 56; + if ((hv || status >= 2) && + (status < ARRAY_SIZE(facility_strings)) && + facility_strings[status]) + facility = facility_strings[status]; + + /* We should not have taken this interrupt in kernel */ + if (!user_mode(regs)) { + pr_emerg("Facility '%s' unavailable (%d) exception in kernel mode at %lx\n", + facility, status, regs->nip); + die("Unexpected facility unavailable exception", regs, SIGABRT); + } + + /* We restore the interrupt state now */ + if (!arch_irq_disabled_regs(regs)) + local_irq_enable(); + if (status == FSCR_DSCR_LG) { /* * User is accessing the DSCR register using the problem @@ -1445,25 +1472,11 @@ void facility_unavailable_exception(struct pt_regs *regs) return; } - if ((hv || status >= 2) && - (status < ARRAY_SIZE(facility_strings)) && - facility_strings[status]) - facility = facility_strings[status]; - - /* We restore the interrupt state now */ - if (!arch_irq_disabled_regs(regs)) - local_irq_enable(); - pr_err_ratelimited("%sFacility '%s' unavailable (%d), exception at 0x%lx, MSR=%lx\n", hv ? "Hypervisor " : "", facility, status, regs->nip, regs->msr); out: - if (user_mode(regs)) { - _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); - return; - } - - die("Unexpected facility unavailable exception", regs, SIGABRT); + _exception(SIGILL, regs, ILL_ILLOPC, regs->nip); } #endif diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 307843d23682..c89ffb88fa3b 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -134,6 +134,20 @@ SECTIONS #ifdef CONFIG_PPC64 . = ALIGN(8); + __stf_entry_barrier_fixup : AT(ADDR(__stf_entry_barrier_fixup) - LOAD_OFFSET) { + __start___stf_entry_barrier_fixup = .; + *(__stf_entry_barrier_fixup) + __stop___stf_entry_barrier_fixup = .; + } + + . = ALIGN(8); + __stf_exit_barrier_fixup : AT(ADDR(__stf_exit_barrier_fixup) - LOAD_OFFSET) { + __start___stf_exit_barrier_fixup = .; + *(__stf_exit_barrier_fixup) + __stop___stf_exit_barrier_fixup = .; + } + + . = ALIGN(8); __rfi_flush_fixup : AT(ADDR(__rfi_flush_fixup) - LOAD_OFFSET) { __start___rfi_flush_fixup = .; *(__rfi_flush_fixup) |