diff options
author | Michael Ellerman <mpe@ellerman.id.au> | 2018-01-21 23:21:14 +1100 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-01-21 23:21:14 +1100 |
commit | ebf0b6a8b1e445d2be66087732aafcda12ab9f59 (patch) | |
tree | f00716a1dbde6b54dea5469ef209baac01883ec3 /arch/powerpc/kernel | |
parent | 5400fc229e6078a6964b15fb98e9a994df3d642a (diff) | |
parent | 1b689a95ce7427075f9ac9fb4aea1af530742b7f (diff) |
Merge branch 'fixes' into next
Merge our fixes branch from the 4.15 cycle.
Unusually the fixes branch saw some significant features merged,
notably the RFI flush patches, so we want the code in next to be
tested against that, to avoid any surprises when the two are merged.
There's also some other work on the panic handling that was reverted
in fixes and we now want to do properly in next, which would conflict.
And we also fix a few other minor merge conflicts.
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/asm-offsets.c | 5 | ||||
-rw-r--r-- | arch/powerpc/kernel/cpu_setup_power.S | 2 | ||||
-rw-r--r-- | arch/powerpc/kernel/entry_64.S | 44 | ||||
-rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 137 | ||||
-rw-r--r-- | arch/powerpc/kernel/fadump.c | 22 | ||||
-rw-r--r-- | arch/powerpc/kernel/process.c | 2 | ||||
-rw-r--r-- | arch/powerpc/kernel/setup-common.c | 37 | ||||
-rw-r--r-- | arch/powerpc/kernel/setup_64.c | 139 | ||||
-rw-r--r-- | arch/powerpc/kernel/vmlinux.lds.S | 9 |
9 files changed, 343 insertions, 54 deletions
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 43a6967d48ad..fa5c4125f42a 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -237,6 +237,11 @@ int main(void) OFFSET(PACA_NMI_EMERG_SP, paca_struct, nmi_emergency_sp); OFFSET(PACA_IN_MCE, paca_struct, in_mce); 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); + #endif OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id); OFFSET(PACAKEXECSTATE, paca_struct, kexec_state); diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S index 730ade48329b..3f30c994e931 100644 --- a/arch/powerpc/kernel/cpu_setup_power.S +++ b/arch/powerpc/kernel/cpu_setup_power.S @@ -98,6 +98,7 @@ _GLOBAL(__setup_cpu_power9) li r0,0 mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 + mtspr SPRN_PID,r0 mfspr r3,SPRN_LPCR LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC) or r3, r3, r4 @@ -121,6 +122,7 @@ _GLOBAL(__restore_cpu_power9) li r0,0 mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 + mtspr SPRN_PID,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/entry_64.S b/arch/powerpc/kernel/entry_64.S index b2995509b01d..2cb5109a7ea3 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -37,6 +37,11 @@ #include <asm/tm.h> #include <asm/ppc-opcode.h> #include <asm/export.h> +#ifdef CONFIG_PPC_BOOK3S +#include <asm/exception-64s.h> +#else +#include <asm/exception-64e.h> +#endif /* * System calls. @@ -261,13 +266,23 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r13,GPR13(r1) /* only restore r13 if returning to usermode */ + ld r2,GPR2(r1) + ld r1,GPR1(r1) + mtlr r4 + mtcr r5 + mtspr SPRN_SRR0,r7 + mtspr SPRN_SRR1,r8 + RFI_TO_USER + b . /* prevent speculative execution */ + + /* exit to kernel */ 1: ld r2,GPR2(r1) ld r1,GPR1(r1) mtlr r4 mtcr r5 mtspr SPRN_SRR0,r7 mtspr SPRN_SRR1,r8 - RFI + RFI_TO_KERNEL b . /* prevent speculative execution */ .Lsyscall_error: @@ -396,8 +411,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) mtmsrd r10, 1 mtspr SPRN_SRR0, r11 mtspr SPRN_SRR1, r12 - - rfid + RFI_TO_USER b . /* prevent speculative execution */ #endif _ASM_NOKPROBE_SYMBOL(system_call_common); @@ -877,7 +891,7 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ACCOUNT_CPU_USER_EXIT(r13, r2, r4) REST_GPR(13, r1) -1: + mtspr SPRN_SRR1,r3 ld r2,_CCR(r1) @@ -890,8 +904,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r3,GPR3(r1) ld r4,GPR4(r1) ld r1,GPR1(r1) + RFI_TO_USER + b . /* prevent speculative execution */ - rfid +1: mtspr SPRN_SRR1,r3 + + ld r2,_CCR(r1) + mtcrf 0xFF,r2 + ld r2,_NIP(r1) + mtspr SPRN_SRR0,r2 + + ld r0,GPR0(r1) + ld r2,GPR2(r1) + ld r3,GPR3(r1) + ld r4,GPR4(r1) + ld r1,GPR1(r1) + RFI_TO_KERNEL b . /* prevent speculative execution */ #endif /* CONFIG_PPC_BOOK3E */ @@ -1081,7 +1109,7 @@ __enter_rtas: mtspr SPRN_SRR0,r5 mtspr SPRN_SRR1,r6 - rfid + RFI_TO_KERNEL b . /* prevent speculative execution */ rtas_return_loc: @@ -1111,7 +1139,7 @@ rtas_return_loc: mtspr SPRN_SRR0,r3 mtspr SPRN_SRR1,r4 - rfid + RFI_TO_KERNEL b . /* prevent speculative execution */ _ASM_NOKPROBE_SYMBOL(__enter_rtas) _ASM_NOKPROBE_SYMBOL(rtas_return_loc) @@ -1184,7 +1212,7 @@ _GLOBAL(enter_prom) LOAD_REG_IMMEDIATE(r12, MSR_SF | MSR_ISF | MSR_LE) andc r11,r11,r12 mtsrr1 r11 - rfid + RFI_TO_KERNEL #endif /* CONFIG_PPC_BOOK3E */ 1: /* Return from OF */ diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 42a47d83282c..9e6882bdc526 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -256,7 +256,7 @@ BEGIN_FTR_SECTION LOAD_HANDLER(r12, machine_check_handle_early) 1: mtspr SPRN_SRR0,r12 mtspr SPRN_SRR1,r11 - rfid + RFI_TO_KERNEL b . /* prevent speculative execution */ 2: /* Stack overflow. Stay on emergency stack and panic. @@ -445,7 +445,7 @@ EXC_COMMON_BEGIN(machine_check_handle_early) li r3,MSR_ME andc r10,r10,r3 /* Turn off MSR_ME */ mtspr SPRN_SRR1,r10 - rfid + RFI_TO_KERNEL b . 2: /* @@ -463,7 +463,7 @@ EXC_COMMON_BEGIN(machine_check_handle_early) */ bl machine_check_queue_event MACHINE_CHECK_HANDLER_WINDUP - rfid + RFI_TO_USER_OR_KERNEL 9: /* Deliver the machine check to host kernel in V mode. */ MACHINE_CHECK_HANDLER_WINDUP @@ -598,6 +598,9 @@ EXC_COMMON_BEGIN(slb_miss_common) stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */ std r10,PACA_EXSLB+EX_LR(r13) /* save LR */ + andi. r9,r11,MSR_PR // Check for exception from userspace + cmpdi cr4,r9,MSR_PR // And save the result in CR4 for later + /* * Test MSR_RI before calling slb_allocate_realmode, because the * MSR in r11 gets clobbered. However we still want to allocate @@ -624,9 +627,12 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) /* All done -- return from exception. */ + bne cr4,1f /* returning to kernel */ + .machine push .machine "power4" mtcrf 0x80,r9 + mtcrf 0x08,r9 /* MSR[PR] indication is in cr4 */ mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */ mtcrf 0x02,r9 /* I/D indication is in cr6 */ mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */ @@ -640,9 +646,30 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) ld r11,PACA_EXSLB+EX_R11(r13) ld r12,PACA_EXSLB+EX_R12(r13) ld r13,PACA_EXSLB+EX_R13(r13) - rfid + RFI_TO_USER + b . /* prevent speculative execution */ +1: +.machine push +.machine "power4" + mtcrf 0x80,r9 + mtcrf 0x08,r9 /* MSR[PR] indication is in cr4 */ + mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */ + mtcrf 0x02,r9 /* I/D indication is in cr6 */ + mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */ +.machine pop + + RESTORE_CTR(r9, PACA_EXSLB) + RESTORE_PPR_PACA(PACA_EXSLB, r9) + mr r3,r12 + ld r9,PACA_EXSLB+EX_R9(r13) + ld r10,PACA_EXSLB+EX_R10(r13) + ld r11,PACA_EXSLB+EX_R11(r13) + ld r12,PACA_EXSLB+EX_R12(r13) + ld r13,PACA_EXSLB+EX_R13(r13) + RFI_TO_KERNEL b . /* prevent speculative execution */ + 2: std r3,PACA_EXSLB+EX_DAR(r13) mr r3,r12 mfspr r11,SPRN_SRR0 @@ -651,7 +678,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) mtspr SPRN_SRR0,r10 ld r10,PACAKMSR(r13) mtspr SPRN_SRR1,r10 - rfid + RFI_TO_KERNEL b . 8: std r3,PACA_EXSLB+EX_DAR(r13) @@ -662,7 +689,7 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) mtspr SPRN_SRR0,r10 ld r10,PACAKMSR(r13) mtspr SPRN_SRR1,r10 - rfid + RFI_TO_KERNEL b . EXC_COMMON_BEGIN(unrecov_slb) @@ -907,7 +934,7 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception) mtspr SPRN_SRR0,r10 ; \ ld r10,PACAKMSR(r13) ; \ mtspr SPRN_SRR1,r10 ; \ - rfid ; \ + RFI_TO_KERNEL ; \ b . ; /* prevent speculative execution */ #ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH @@ -923,7 +950,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \ xori r12,r12,MSR_LE ; \ mtspr SPRN_SRR1,r12 ; \ mr r13,r9 ; \ - rfid ; /* return to userspace */ \ + RFI_TO_USER ; /* return to userspace */ \ b . ; /* prevent speculative execution */ #else #define SYSCALL_FASTENDIAN_TEST @@ -1069,7 +1096,7 @@ TRAMP_REAL_BEGIN(hmi_exception_early) mtcr r11 REST_GPR(11, r1) ld r1,GPR1(r1) - hrfid + HRFI_TO_USER_OR_KERNEL 1: mtcr r11 REST_GPR(11, r1) @@ -1320,7 +1347,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR) ld r11,PACA_EXGEN+EX_R11(r13) ld r12,PACA_EXGEN+EX_R12(r13) ld r13,PACA_EXGEN+EX_R13(r13) - HRFID + HRFI_TO_UNKNOWN b . #endif @@ -1424,10 +1451,94 @@ masked_##_H##interrupt: \ ld r10,PACA_EXGEN+EX_R10(r13); \ ld r11,PACA_EXGEN+EX_R11(r13); \ /* returns to kernel where r13 must be set up, so don't restore it */ \ - ##_H##rfid; \ + ##_H##RFI_TO_KERNEL; \ b .; \ MASKED_DEC_HANDLER(_H) +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 + 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 */ + 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 + +TRAMP_REAL_BEGIN(hrfi_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 + 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 */ + 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 + /* * Real mode exceptions actually use this too, but alternate * instruction code patches (which end up in the common .text area) @@ -1447,7 +1558,7 @@ TRAMP_REAL_BEGIN(kvmppc_skip_interrupt) addi r13, r13, 4 mtspr SPRN_SRR0, r13 GET_SCRATCH0(r13) - rfid + RFI_TO_KERNEL b . TRAMP_REAL_BEGIN(kvmppc_skip_Hinterrupt) @@ -1459,7 +1570,7 @@ TRAMP_REAL_BEGIN(kvmppc_skip_Hinterrupt) addi r13, r13, 4 mtspr SPRN_HSRR0, r13 GET_SCRATCH0(r13) - hrfid + HRFI_TO_KERNEL b . #endif diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index 04ea5c04fd24..3c2c2688918f 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -1462,25 +1462,6 @@ static void fadump_init_files(void) return; } -static int fadump_panic_event(struct notifier_block *this, - unsigned long event, void *ptr) -{ - /* - * If firmware-assisted dump has been registered then trigger - * firmware-assisted dump and let firmware handle everything - * else. If this returns, then fadump was not registered, so - * go through the rest of the panic path. - */ - crash_fadump(NULL, ptr); - - return NOTIFY_DONE; -} - -static struct notifier_block fadump_panic_block = { - .notifier_call = fadump_panic_event, - .priority = INT_MIN /* may not return; must be done last */ -}; - /* * Prepare for firmware-assisted dump. */ @@ -1513,9 +1494,6 @@ int __init setup_fadump(void) init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start); fadump_init_files(); - atomic_notifier_chain_register(&panic_notifier_list, - &fadump_panic_block); - return 1; } subsys_initcall(setup_fadump); diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 755fd7e23ed4..2fd01c9045ba 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1409,7 +1409,7 @@ void show_regs(struct pt_regs * regs) printk("NIP: "REG" LR: "REG" CTR: "REG"\n", regs->nip, regs->link, regs->ctr); - printk("REGS: %p TRAP: %04lx %s (%s)\n", + printk("REGS: %px TRAP: %04lx %s (%s)\n", regs, regs->trap, print_tainted(), init_utsname()->release); printk("MSR: "REG" ", regs->msr); print_msr_bits(regs->msr); diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 24da91768133..af128ee67248 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 @@ -356,8 +348,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) #endif seq_printf(m, "\n"); - 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); @@ -706,6 +696,30 @@ int check_legacy_ioport(unsigned long base_port) } EXPORT_SYMBOL(check_legacy_ioport); +static int ppc_panic_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + /* + * If firmware-assisted dump has been registered then trigger + * firmware-assisted dump and let firmware handle everything else. + */ + crash_fadump(NULL, ptr); + ppc_md.panic(ptr); /* May not return */ + return NOTIFY_DONE; +} + +static struct notifier_block ppc_panic_block = { + .notifier_call = ppc_panic_event, + .priority = INT_MIN /* may not return; must be done last */ +}; + +void __init setup_panic(void) +{ + if (!ppc_md.panic) + return; + atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block); +} + #ifdef CONFIG_CHECK_CACHE_COHERENCY /* * For platforms that have configurable cache-coherency. This function @@ -850,6 +864,9 @@ void __init setup_arch(char **cmdline_p) /* Probe the machine type, establish ppc_md. */ probe_machine(); + /* Setup panic notifier if requested by the platform. */ + setup_panic(); + /* * Configure ppc_md.power_save (ppc32 only, 64-bit machines do * it from their respective probe() function. diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 896dacef2f2d..d1fa0e91f526 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -36,6 +36,7 @@ #include <linux/memory.h> #include <linux/nmi.h> +#include <asm/debugfs.h> #include <asm/io.h> #include <asm/kdump.h> #include <asm/prom.h> @@ -808,3 +809,141 @@ static int __init disable_hardlockup_detector(void) return 0; } early_initcall(disable_hardlockup_detector); + +#ifdef CONFIG_PPC_BOOK3S_64 +static enum l1d_flush_type enabled_flush_types; +static void *l1d_flush_fallback_area; +static bool no_rfi_flush; +bool rfi_flush; + +static int __init handle_no_rfi_flush(char *p) +{ + pr_info("rfi-flush: disabled on command line."); + no_rfi_flush = true; + return 0; +} +early_param("no_rfi_flush", handle_no_rfi_flush); + +/* + * The RFI flush is not KPTI, but because users will see doco that says to use + * nopti we hijack that option here to also disable the RFI flush. + */ +static int __init handle_no_pti(char *p) +{ + pr_info("rfi-flush: disabling due to 'nopti' on command line.\n"); + handle_no_rfi_flush(NULL); + return 0; +} +early_param("nopti", handle_no_pti); + +static void do_nothing(void *unused) +{ + /* + * We don't need to do the flush explicitly, just enter+exit kernel is + * sufficient, the RFI exit handlers will do the right thing. + */ +} + +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); + } else + do_rfi_flush_fixups(L1D_FLUSH_NONE); + + rfi_flush = enable; +} + +static void init_fallback_flush(void) +{ + u64 l1d_size, limit; + int cpu; + + l1d_size = ppc64_caches.l1d.size; + limit = min(ppc64_bolted_size(), ppc64_rma_size); + + /* + * Align to L1d size, and size it at 2x L1d size, to catch possible + * hardware prefetch runoff. We don't have a recipe for load patterns to + * reliably avoid the prefetcher. + */ + l1d_flush_fallback_area = __va(memblock_alloc_base(l1d_size * 2, l1d_size, limit)); + 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; + } +} + +void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) +{ + if (types & L1D_FLUSH_FALLBACK) { + pr_info("rfi-flush: Using fallback displacement flush\n"); + init_fallback_flush(); + } + + if (types & L1D_FLUSH_ORI) + pr_info("rfi-flush: Using ori type flush\n"); + + if (types & L1D_FLUSH_MTTRIG) + pr_info("rfi-flush: Using mttrig type flush\n"); + + enabled_flush_types = types; + + if (!no_rfi_flush) + rfi_flush_enable(enable); +} + +#ifdef CONFIG_DEBUG_FS +static int rfi_flush_set(void *data, u64 val) +{ + if (val == 1) + rfi_flush_enable(true); + else if (val == 0) + rfi_flush_enable(false); + else + return -EINVAL; + + return 0; +} + +static int rfi_flush_get(void *data, u64 *val) +{ + *val = rfi_flush ? 1 : 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set, "%llu\n"); + +static __init int rfi_flush_debugfs_init(void) +{ + debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL, &fops_rfi_flush); + return 0; +} +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/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 51e4ec92ade1..6507138ebe10 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -132,6 +132,15 @@ SECTIONS /* Read-only data */ RO_DATA(PAGE_SIZE) +#ifdef CONFIG_PPC64 + . = ALIGN(8); + __rfi_flush_fixup : AT(ADDR(__rfi_flush_fixup) - LOAD_OFFSET) { + __start___rfi_flush_fixup = .; + *(__rfi_flush_fixup) + __stop___rfi_flush_fixup = .; + } +#endif + EXCEPTION_TABLE(0) NOTES :kernel :notes |