diff options
Diffstat (limited to 'arch/powerpc/lib/feature-fixups.c')
| -rw-r--r-- | arch/powerpc/lib/feature-fixups.c | 1012 |
1 files changed, 1012 insertions, 0 deletions
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c new file mode 100644 index 0000000000..4f82581ca2 --- /dev/null +++ b/arch/powerpc/lib/feature-fixups.c @@ -0,0 +1,1012 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org) + * + * Modifications for ppc64: + * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com> + * + * Copyright 2008 Michael Ellerman, IBM Corporation. + */ + +#include <linux/types.h> +#include <linux/jump_label.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/sched/mm.h> +#include <linux/stop_machine.h> +#include <asm/cputable.h> +#include <asm/code-patching.h> +#include <asm/interrupt.h> +#include <asm/page.h> +#include <asm/sections.h> +#include <asm/setup.h> +#include <asm/security_features.h> +#include <asm/firmware.h> +#include <asm/inst.h> + +struct fixup_entry { + unsigned long mask; + unsigned long value; + long start_off; + long end_off; + long alt_start_off; + long alt_end_off; +}; + +static u32 *calc_addr(struct fixup_entry *fcur, long offset) +{ + /* + * We store the offset to the code as a negative offset from + * the start of the alt_entry, to support the VDSO. This + * routine converts that back into an actual address. + */ + return (u32 *)((unsigned long)fcur + offset); +} + +static int patch_alt_instruction(u32 *src, u32 *dest, u32 *alt_start, u32 *alt_end) +{ + int err; + ppc_inst_t instr; + + instr = ppc_inst_read(src); + + if (instr_is_relative_branch(ppc_inst_read(src))) { + u32 *target = (u32 *)branch_target(src); + + /* Branch within the section doesn't need translating */ + if (target < alt_start || target > alt_end) { + err = translate_branch(&instr, dest, src); + if (err) + return 1; + } + } + + raw_patch_instruction(dest, instr); + + return 0; +} + +static int patch_feature_section_mask(unsigned long value, unsigned long mask, + struct fixup_entry *fcur) +{ + u32 *start, *end, *alt_start, *alt_end, *src, *dest; + + start = calc_addr(fcur, fcur->start_off); + end = calc_addr(fcur, fcur->end_off); + alt_start = calc_addr(fcur, fcur->alt_start_off); + alt_end = calc_addr(fcur, fcur->alt_end_off); + + if ((alt_end - alt_start) > (end - start)) + return 1; + + if ((value & fcur->mask & mask) == (fcur->value & mask)) + return 0; + + src = alt_start; + dest = start; + + for (; src < alt_end; src = ppc_inst_next(src, src), + dest = ppc_inst_next(dest, dest)) { + if (patch_alt_instruction(src, dest, alt_start, alt_end)) + return 1; + } + + for (; dest < end; dest++) + raw_patch_instruction(dest, ppc_inst(PPC_RAW_NOP())); + + return 0; +} + +static void do_feature_fixups_mask(unsigned long value, unsigned long mask, + void *fixup_start, void *fixup_end) +{ + struct fixup_entry *fcur, *fend; + + fcur = fixup_start; + fend = fixup_end; + + for (; fcur < fend; fcur++) { + if (patch_feature_section_mask(value, mask, fcur)) { + WARN_ON(1); + printk("Unable to patch feature section at %p - %p" \ + " with %p - %p\n", + calc_addr(fcur, fcur->start_off), + calc_addr(fcur, fcur->end_off), + calc_addr(fcur, fcur->alt_start_off), + calc_addr(fcur, fcur->alt_end_off)); + } + } +} + +void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end) +{ + do_feature_fixups_mask(value, ~0, fixup_start, fixup_end); +} + +#ifdef CONFIG_PPC_BARRIER_NOSPEC +static bool is_fixup_addr_valid(void *dest, size_t size) +{ + return system_state < SYSTEM_FREEING_INITMEM || + !init_section_contains(dest, size); +} + +static int do_patch_fixups(long *start, long *end, unsigned int *instrs, int num) +{ + int i; + + for (i = 0; start < end; start++, i++) { + int j; + unsigned int *dest = (void *)start + *start; + + if (!is_fixup_addr_valid(dest, sizeof(*instrs) * num)) + continue; + + pr_devel("patching dest %lx\n", (unsigned long)dest); + + for (j = 0; j < num; j++) + patch_instruction(dest + j, ppc_inst(instrs[j])); + } + return i; +} +#endif + +#ifdef CONFIG_PPC_BOOK3S_64 +static int do_patch_entry_fixups(long *start, long *end, unsigned int *instrs, + bool do_fallback, void *fallback) +{ + int i; + + for (i = 0; start < end; start++, i++) { + unsigned int *dest = (void *)start + *start; + + if (!is_fixup_addr_valid(dest, sizeof(*instrs) * 3)) + continue; + + pr_devel("patching dest %lx\n", (unsigned long)dest); + + // See comment in do_entry_flush_fixups() RE order of patching + if (do_fallback) { + patch_instruction(dest, ppc_inst(instrs[0])); + patch_instruction(dest + 2, ppc_inst(instrs[2])); + patch_branch(dest + 1, (unsigned long)fallback, BRANCH_SET_LINK); + } else { + patch_instruction(dest + 1, ppc_inst(instrs[1])); + patch_instruction(dest + 2, ppc_inst(instrs[2])); + patch_instruction(dest, ppc_inst(instrs[0])); + } + } + return i; +} + +static void do_stf_entry_barrier_fixups(enum stf_barrier_type types) +{ + unsigned int instrs[3]; + long *start, *end; + int i; + + start = PTRRELOC(&__start___stf_entry_barrier_fixup); + end = PTRRELOC(&__stop___stf_entry_barrier_fixup); + + instrs[0] = PPC_RAW_NOP(); + instrs[1] = PPC_RAW_NOP(); + instrs[2] = PPC_RAW_NOP(); + + i = 0; + if (types & STF_BARRIER_FALLBACK) { + instrs[i++] = PPC_RAW_MFLR(_R10); + instrs[i++] = PPC_RAW_NOP(); /* branch patched below */ + instrs[i++] = PPC_RAW_MTLR(_R10); + } else if (types & STF_BARRIER_EIEIO) { + instrs[i++] = PPC_RAW_EIEIO() | 0x02000000; /* eieio + bit 6 hint */ + } else if (types & STF_BARRIER_SYNC_ORI) { + instrs[i++] = PPC_RAW_SYNC(); + instrs[i++] = PPC_RAW_LD(_R10, _R13, 0); + instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + } + + i = do_patch_entry_fixups(start, end, instrs, types & STF_BARRIER_FALLBACK, + &stf_barrier_fallback); + + printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i, + (types == STF_BARRIER_NONE) ? "no" : + (types == STF_BARRIER_FALLBACK) ? "fallback" : + (types == STF_BARRIER_EIEIO) ? "eieio" : + (types == (STF_BARRIER_SYNC_ORI)) ? "hwsync" + : "unknown"); +} + +static void do_stf_exit_barrier_fixups(enum stf_barrier_type types) +{ + unsigned int instrs[6]; + long *start, *end; + int i; + + start = PTRRELOC(&__start___stf_exit_barrier_fixup); + end = PTRRELOC(&__stop___stf_exit_barrier_fixup); + + instrs[0] = PPC_RAW_NOP(); + instrs[1] = PPC_RAW_NOP(); + instrs[2] = PPC_RAW_NOP(); + instrs[3] = PPC_RAW_NOP(); + instrs[4] = PPC_RAW_NOP(); + instrs[5] = PPC_RAW_NOP(); + + i = 0; + if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) { + if (cpu_has_feature(CPU_FTR_HVMODE)) { + instrs[i++] = PPC_RAW_MTSPR(SPRN_HSPRG1, _R13); + instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_HSPRG0); + } else { + instrs[i++] = PPC_RAW_MTSPR(SPRN_SPRG2, _R13); + instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_SPRG1); + } + instrs[i++] = PPC_RAW_SYNC(); + instrs[i++] = PPC_RAW_LD(_R13, _R13, 0); + instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + if (cpu_has_feature(CPU_FTR_HVMODE)) + instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_HSPRG1); + else + instrs[i++] = PPC_RAW_MFSPR(_R13, SPRN_SPRG2); + } else if (types & STF_BARRIER_EIEIO) { + instrs[i++] = PPC_RAW_EIEIO() | 0x02000000; /* eieio + bit 6 hint */ + } + + i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); + + printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i, + (types == STF_BARRIER_NONE) ? "no" : + (types == STF_BARRIER_FALLBACK) ? "fallback" : + (types == STF_BARRIER_EIEIO) ? "eieio" : + (types == (STF_BARRIER_SYNC_ORI)) ? "hwsync" + : "unknown"); +} + +static bool stf_exit_reentrant = false; +static bool rfi_exit_reentrant = false; +static DEFINE_MUTEX(exit_flush_lock); + +static int __do_stf_barrier_fixups(void *data) +{ + enum stf_barrier_type *types = data; + + do_stf_entry_barrier_fixups(*types); + do_stf_exit_barrier_fixups(*types); + + return 0; +} + +void do_stf_barrier_fixups(enum stf_barrier_type types) +{ + /* + * The call to the fallback entry flush, and the fallback/sync-ori exit + * flush can not be safely patched in/out while other CPUs are + * executing them. So call __do_stf_barrier_fixups() on one CPU while + * all other CPUs spin in the stop machine core with interrupts hard + * disabled. + * + * The branch to mark interrupt exits non-reentrant is enabled first, + * then stop_machine runs which will ensure all CPUs are out of the + * low level interrupt exit code before patching. After the patching, + * if allowed, then flip the branch to allow fast exits. + */ + + // Prevent static key update races with do_rfi_flush_fixups() + mutex_lock(&exit_flush_lock); + static_branch_enable(&interrupt_exit_not_reentrant); + + stop_machine(__do_stf_barrier_fixups, &types, NULL); + + if ((types & STF_BARRIER_FALLBACK) || (types & STF_BARRIER_SYNC_ORI)) + stf_exit_reentrant = false; + else + stf_exit_reentrant = true; + + if (stf_exit_reentrant && rfi_exit_reentrant) + static_branch_disable(&interrupt_exit_not_reentrant); + + mutex_unlock(&exit_flush_lock); +} + +void do_uaccess_flush_fixups(enum l1d_flush_type types) +{ + unsigned int instrs[4]; + long *start, *end; + int i; + + start = PTRRELOC(&__start___uaccess_flush_fixup); + end = PTRRELOC(&__stop___uaccess_flush_fixup); + + instrs[0] = PPC_RAW_NOP(); + instrs[1] = PPC_RAW_NOP(); + instrs[2] = PPC_RAW_NOP(); + instrs[3] = PPC_RAW_BLR(); + + i = 0; + if (types == L1D_FLUSH_FALLBACK) { + instrs[3] = PPC_RAW_NOP(); + /* fallthrough to fallback flush */ + } + + if (types & L1D_FLUSH_ORI) { + instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ + } + + if (types & L1D_FLUSH_MTTRIG) + instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); + + i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); + + printk(KERN_DEBUG "uaccess-flush: patched %d locations (%s flush)\n", i, + (types == L1D_FLUSH_NONE) ? "no" : + (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : + (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) + ? "ori+mttrig type" + : "ori type" : + (types & L1D_FLUSH_MTTRIG) ? "mttrig type" + : "unknown"); +} + +static int __do_entry_flush_fixups(void *data) +{ + enum l1d_flush_type types = *(enum l1d_flush_type *)data; + unsigned int instrs[3]; + long *start, *end; + int i; + + instrs[0] = PPC_RAW_NOP(); + instrs[1] = PPC_RAW_NOP(); + instrs[2] = PPC_RAW_NOP(); + + i = 0; + if (types == L1D_FLUSH_FALLBACK) { + instrs[i++] = PPC_RAW_MFLR(_R10); + instrs[i++] = PPC_RAW_NOP(); /* branch patched below */ + instrs[i++] = PPC_RAW_MTLR(_R10); + } + + if (types & L1D_FLUSH_ORI) { + instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ + } + + if (types & L1D_FLUSH_MTTRIG) + instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); + + /* + * If we're patching in or out the fallback flush we need to be careful about the + * order in which we patch instructions. That's because it's possible we could + * take a page fault after patching one instruction, so the sequence of + * instructions must be safe even in a half patched state. + * + * To make that work, when patching in the fallback flush we patch in this order: + * - the mflr (dest) + * - the mtlr (dest + 2) + * - the branch (dest + 1) + * + * That ensures the sequence is safe to execute at any point. In contrast if we + * patch the mtlr last, it's possible we could return from the branch and not + * restore LR, leading to a crash later. + * + * When patching out the fallback flush (either with nops or another flush type), + * we patch in this order: + * - the branch (dest + 1) + * - the mtlr (dest + 2) + * - the mflr (dest) + * + * Note we are protected by stop_machine() from other CPUs executing the code in a + * semi-patched state. + */ + + start = PTRRELOC(&__start___entry_flush_fixup); + end = PTRRELOC(&__stop___entry_flush_fixup); + i = do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK, + &entry_flush_fallback); + + start = PTRRELOC(&__start___scv_entry_flush_fixup); + end = PTRRELOC(&__stop___scv_entry_flush_fixup); + i += do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK, + &scv_entry_flush_fallback); + + printk(KERN_DEBUG "entry-flush: patched %d locations (%s flush)\n", i, + (types == L1D_FLUSH_NONE) ? "no" : + (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : + (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) + ? "ori+mttrig type" + : "ori type" : + (types & L1D_FLUSH_MTTRIG) ? "mttrig type" + : "unknown"); + + return 0; +} + +void do_entry_flush_fixups(enum l1d_flush_type types) +{ + /* + * The call to the fallback flush can not be safely patched in/out while + * other CPUs are executing it. So call __do_entry_flush_fixups() on one + * CPU while all other CPUs spin in the stop machine core with interrupts + * hard disabled. + */ + stop_machine(__do_entry_flush_fixups, &types, NULL); +} + +static int __do_rfi_flush_fixups(void *data) +{ + enum l1d_flush_type types = *(enum l1d_flush_type *)data; + unsigned int instrs[3]; + long *start, *end; + int i; + + start = PTRRELOC(&__start___rfi_flush_fixup); + end = PTRRELOC(&__stop___rfi_flush_fixup); + + instrs[0] = PPC_RAW_NOP(); + instrs[1] = PPC_RAW_NOP(); + instrs[2] = PPC_RAW_NOP(); + + if (types & L1D_FLUSH_FALLBACK) + /* b .+16 to fallback flush */ + instrs[0] = PPC_RAW_BRANCH(16); + + i = 0; + if (types & L1D_FLUSH_ORI) { + instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + instrs[i++] = PPC_RAW_ORI(_R30, _R30, 0); /* L1d flush */ + } + + if (types & L1D_FLUSH_MTTRIG) + instrs[i++] = PPC_RAW_MTSPR(SPRN_TRIG2, _R0); + + i = do_patch_fixups(start, end, instrs, ARRAY_SIZE(instrs)); + + printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i, + (types == L1D_FLUSH_NONE) ? "no" : + (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" : + (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG) + ? "ori+mttrig type" + : "ori type" : + (types & L1D_FLUSH_MTTRIG) ? "mttrig type" + : "unknown"); + + return 0; +} + +void do_rfi_flush_fixups(enum l1d_flush_type types) +{ + /* + * stop_machine gets all CPUs out of the interrupt exit handler same + * as do_stf_barrier_fixups. do_rfi_flush_fixups patching can run + * without stop_machine, so this could be achieved with a broadcast + * IPI instead, but this matches the stf sequence. + */ + + // Prevent static key update races with do_stf_barrier_fixups() + mutex_lock(&exit_flush_lock); + static_branch_enable(&interrupt_exit_not_reentrant); + + stop_machine(__do_rfi_flush_fixups, &types, NULL); + + if (types & L1D_FLUSH_FALLBACK) + rfi_exit_reentrant = false; + else + rfi_exit_reentrant = true; + + if (stf_exit_reentrant && rfi_exit_reentrant) + static_branch_disable(&interrupt_exit_not_reentrant); + + mutex_unlock(&exit_flush_lock); +} + +void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end) +{ + unsigned int instr; + long *start, *end; + int i; + + start = fixup_start; + end = fixup_end; + + instr = PPC_RAW_NOP(); + + if (enable) { + pr_info("barrier-nospec: using ORI speculation barrier\n"); + instr = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */ + } + + i = do_patch_fixups(start, end, &instr, 1); + + printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i); +} + +#endif /* CONFIG_PPC_BOOK3S_64 */ + +#ifdef CONFIG_PPC_BARRIER_NOSPEC +void do_barrier_nospec_fixups(bool enable) +{ + void *start, *end; + + start = PTRRELOC(&__start___barrier_nospec_fixup); + end = PTRRELOC(&__stop___barrier_nospec_fixup); + + do_barrier_nospec_fixups_range(enable, start, end); +} +#endif /* CONFIG_PPC_BARRIER_NOSPEC */ + +#ifdef CONFIG_PPC_E500 +void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end) +{ + unsigned int instr[2]; + long *start, *end; + int i; + + start = fixup_start; + end = fixup_end; + + instr[0] = PPC_RAW_NOP(); + instr[1] = PPC_RAW_NOP(); + + if (enable) { + pr_info("barrier-nospec: using isync; sync as speculation barrier\n"); + instr[0] = PPC_RAW_ISYNC(); + instr[1] = PPC_RAW_SYNC(); + } + + i = do_patch_fixups(start, end, instr, ARRAY_SIZE(instr)); + + printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i); +} + +static void __init patch_btb_flush_section(long *curr) +{ + unsigned int *start, *end; + + start = (void *)curr + *curr; + end = (void *)curr + *(curr + 1); + for (; start < end; start++) { + pr_devel("patching dest %lx\n", (unsigned long)start); + patch_instruction(start, ppc_inst(PPC_RAW_NOP())); + } +} + +void __init do_btb_flush_fixups(void) +{ + long *start, *end; + + start = PTRRELOC(&__start__btb_flush_fixup); + end = PTRRELOC(&__stop__btb_flush_fixup); + + for (; start < end; start += 2) + patch_btb_flush_section(start); +} +#endif /* CONFIG_PPC_E500 */ + +void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end) +{ + long *start, *end; + u32 *dest; + + if (!(value & CPU_FTR_LWSYNC)) + return ; + + start = fixup_start; + end = fixup_end; + + for (; start < end; start++) { + dest = (void *)start + *start; + raw_patch_instruction(dest, ppc_inst(PPC_INST_LWSYNC)); + } +} + +static void __init do_final_fixups(void) +{ +#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE) + ppc_inst_t inst; + u32 *src, *dest, *end; + + if (PHYSICAL_START == 0) + return; + + src = (u32 *)(KERNELBASE + PHYSICAL_START); + dest = (u32 *)KERNELBASE; + end = (void *)src + (__end_interrupts - _stext); + + while (src < end) { + inst = ppc_inst_read(src); + raw_patch_instruction(dest, inst); + src = ppc_inst_next(src, src); + dest = ppc_inst_next(dest, dest); + } +#endif +} + +static unsigned long __initdata saved_cpu_features; +static unsigned int __initdata saved_mmu_features; +#ifdef CONFIG_PPC64 +static unsigned long __initdata saved_firmware_features; +#endif + +void __init apply_feature_fixups(void) +{ + struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec)); + + *PTRRELOC(&saved_cpu_features) = spec->cpu_features; + *PTRRELOC(&saved_mmu_features) = spec->mmu_features; + + /* + * Apply the CPU-specific and firmware specific fixups to kernel text + * (nop out sections not relevant to this CPU or this firmware). + */ + do_feature_fixups(spec->cpu_features, + PTRRELOC(&__start___ftr_fixup), + PTRRELOC(&__stop___ftr_fixup)); + + do_feature_fixups(spec->mmu_features, + PTRRELOC(&__start___mmu_ftr_fixup), + PTRRELOC(&__stop___mmu_ftr_fixup)); + + do_lwsync_fixups(spec->cpu_features, + PTRRELOC(&__start___lwsync_fixup), + PTRRELOC(&__stop___lwsync_fixup)); + +#ifdef CONFIG_PPC64 + saved_firmware_features = powerpc_firmware_features; + do_feature_fixups(powerpc_firmware_features, + &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup); +#endif + do_final_fixups(); +} + +void __init update_mmu_feature_fixups(unsigned long mask) +{ + saved_mmu_features &= ~mask; + saved_mmu_features |= cur_cpu_spec->mmu_features & mask; + + do_feature_fixups_mask(cur_cpu_spec->mmu_features, mask, + PTRRELOC(&__start___mmu_ftr_fixup), + PTRRELOC(&__stop___mmu_ftr_fixup)); + mmu_feature_keys_init(); +} + +void __init setup_feature_keys(void) +{ + /* + * Initialise jump label. This causes all the cpu/mmu_has_feature() + * checks to take on their correct polarity based on the current set of + * CPU/MMU features. + */ + jump_label_init(); + cpu_feature_keys_init(); + mmu_feature_keys_init(); +} + +static int __init check_features(void) +{ + WARN(saved_cpu_features != cur_cpu_spec->cpu_features, + "CPU features changed after feature patching!\n"); + WARN(saved_mmu_features != cur_cpu_spec->mmu_features, + "MMU features changed after feature patching!\n"); +#ifdef CONFIG_PPC64 + WARN(saved_firmware_features != powerpc_firmware_features, + "Firmware features changed after feature patching!\n"); +#endif + + return 0; +} +late_initcall(check_features); + +#ifdef CONFIG_FTR_FIXUP_SELFTEST + +#define check(x) \ + if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__); + +static int patch_feature_section(unsigned long value, struct fixup_entry *fcur) +{ + return patch_feature_section_mask(value, ~0, fcur); +} + +/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */ +static struct fixup_entry fixup; + +static long __init calc_offset(struct fixup_entry *entry, unsigned int *p) +{ + return (unsigned long)p - (unsigned long)entry; +} + +static void __init test_basic_patching(void) +{ + extern unsigned int ftr_fixup_test1[]; + extern unsigned int end_ftr_fixup_test1[]; + extern unsigned int ftr_fixup_test1_orig[]; + extern unsigned int ftr_fixup_test1_expected[]; + int size = 4 * (end_ftr_fixup_test1 - ftr_fixup_test1); + + fixup.value = fixup.mask = 8; + fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2); + fixup.alt_start_off = fixup.alt_end_off = 0; + + /* Sanity check */ + check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); + + /* Check we don't patch if the value matches */ + patch_feature_section(8, &fixup); + check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); + + /* Check we do patch if the value doesn't match */ + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0); + + /* Check we do patch if the mask doesn't match */ + memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size); + check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0); + patch_feature_section(~8, &fixup); + check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0); +} + +static void __init test_alternative_patching(void) +{ + extern unsigned int ftr_fixup_test2[]; + extern unsigned int end_ftr_fixup_test2[]; + extern unsigned int ftr_fixup_test2_orig[]; + extern unsigned int ftr_fixup_test2_alt[]; + extern unsigned int ftr_fixup_test2_expected[]; + int size = 4 * (end_ftr_fixup_test2 - ftr_fixup_test2); + + fixup.value = fixup.mask = 0xF; + fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2); + fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt); + fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1); + + /* Sanity check */ + check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); + + /* Check we don't patch if the value matches */ + patch_feature_section(0xF, &fixup); + check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); + + /* Check we do patch if the value doesn't match */ + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0); + + /* Check we do patch if the mask doesn't match */ + memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size); + check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0); + patch_feature_section(~0xF, &fixup); + check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0); +} + +static void __init test_alternative_case_too_big(void) +{ + extern unsigned int ftr_fixup_test3[]; + extern unsigned int end_ftr_fixup_test3[]; + extern unsigned int ftr_fixup_test3_orig[]; + extern unsigned int ftr_fixup_test3_alt[]; + int size = 4 * (end_ftr_fixup_test3 - ftr_fixup_test3); + + fixup.value = fixup.mask = 0xC; + fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2); + fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt); + fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2); + + /* Sanity check */ + check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); + + /* Expect nothing to be patched, and the error returned to us */ + check(patch_feature_section(0xF, &fixup) == 1); + check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); + check(patch_feature_section(0, &fixup) == 1); + check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); + check(patch_feature_section(~0xF, &fixup) == 1); + check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0); +} + +static void __init test_alternative_case_too_small(void) +{ + extern unsigned int ftr_fixup_test4[]; + extern unsigned int end_ftr_fixup_test4[]; + extern unsigned int ftr_fixup_test4_orig[]; + extern unsigned int ftr_fixup_test4_alt[]; + extern unsigned int ftr_fixup_test4_expected[]; + int size = 4 * (end_ftr_fixup_test4 - ftr_fixup_test4); + unsigned long flag; + + /* Check a high-bit flag */ + flag = 1UL << ((sizeof(unsigned long) - 1) * 8); + fixup.value = fixup.mask = flag; + fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5); + fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt); + fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2); + + /* Sanity check */ + check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); + + /* Check we don't patch if the value matches */ + patch_feature_section(flag, &fixup); + check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); + + /* Check we do patch if the value doesn't match */ + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0); + + /* Check we do patch if the mask doesn't match */ + memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size); + check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0); + patch_feature_section(~flag, &fixup); + check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0); +} + +static void test_alternative_case_with_branch(void) +{ + extern unsigned int ftr_fixup_test5[]; + extern unsigned int end_ftr_fixup_test5[]; + extern unsigned int ftr_fixup_test5_expected[]; + int size = 4 * (end_ftr_fixup_test5 - ftr_fixup_test5); + + check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0); +} + +static void __init test_alternative_case_with_external_branch(void) +{ + extern unsigned int ftr_fixup_test6[]; + extern unsigned int end_ftr_fixup_test6[]; + extern unsigned int ftr_fixup_test6_expected[]; + int size = 4 * (end_ftr_fixup_test6 - ftr_fixup_test6); + + check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0); +} + +static void __init test_alternative_case_with_branch_to_end(void) +{ + extern unsigned int ftr_fixup_test7[]; + extern unsigned int end_ftr_fixup_test7[]; + extern unsigned int ftr_fixup_test7_expected[]; + int size = 4 * (end_ftr_fixup_test7 - ftr_fixup_test7); + + check(memcmp(ftr_fixup_test7, ftr_fixup_test7_expected, size) == 0); +} + +static void __init test_cpu_macros(void) +{ + extern u8 ftr_fixup_test_FTR_macros[]; + extern u8 ftr_fixup_test_FTR_macros_expected[]; + unsigned long size = ftr_fixup_test_FTR_macros_expected - + ftr_fixup_test_FTR_macros; + + /* The fixups have already been done for us during boot */ + check(memcmp(ftr_fixup_test_FTR_macros, + ftr_fixup_test_FTR_macros_expected, size) == 0); +} + +static void __init test_fw_macros(void) +{ +#ifdef CONFIG_PPC64 + extern u8 ftr_fixup_test_FW_FTR_macros[]; + extern u8 ftr_fixup_test_FW_FTR_macros_expected[]; + unsigned long size = ftr_fixup_test_FW_FTR_macros_expected - + ftr_fixup_test_FW_FTR_macros; + + /* The fixups have already been done for us during boot */ + check(memcmp(ftr_fixup_test_FW_FTR_macros, + ftr_fixup_test_FW_FTR_macros_expected, size) == 0); +#endif +} + +static void __init test_lwsync_macros(void) +{ + extern u8 lwsync_fixup_test[]; + extern u8 end_lwsync_fixup_test[]; + extern u8 lwsync_fixup_test_expected_LWSYNC[]; + extern u8 lwsync_fixup_test_expected_SYNC[]; + unsigned long size = end_lwsync_fixup_test - + lwsync_fixup_test; + + /* The fixups have already been done for us during boot */ + if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) { + check(memcmp(lwsync_fixup_test, + lwsync_fixup_test_expected_LWSYNC, size) == 0); + } else { + check(memcmp(lwsync_fixup_test, + lwsync_fixup_test_expected_SYNC, size) == 0); + } +} + +#ifdef CONFIG_PPC64 +static void __init test_prefix_patching(void) +{ + extern unsigned int ftr_fixup_prefix1[]; + extern unsigned int end_ftr_fixup_prefix1[]; + extern unsigned int ftr_fixup_prefix1_orig[]; + extern unsigned int ftr_fixup_prefix1_expected[]; + int size = sizeof(unsigned int) * (end_ftr_fixup_prefix1 - ftr_fixup_prefix1); + + fixup.value = fixup.mask = 8; + fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix1 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix1 + 3); + fixup.alt_start_off = fixup.alt_end_off = 0; + + /* Sanity check */ + check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) == 0); + + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_expected, size) == 0); + check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) != 0); +} + +static void __init test_prefix_alt_patching(void) +{ + extern unsigned int ftr_fixup_prefix2[]; + extern unsigned int end_ftr_fixup_prefix2[]; + extern unsigned int ftr_fixup_prefix2_orig[]; + extern unsigned int ftr_fixup_prefix2_expected[]; + extern unsigned int ftr_fixup_prefix2_alt[]; + int size = sizeof(unsigned int) * (end_ftr_fixup_prefix2 - ftr_fixup_prefix2); + + fixup.value = fixup.mask = 8; + fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix2 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix2 + 3); + fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix2_alt); + fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix2_alt + 2); + /* Sanity check */ + check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) == 0); + + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_expected, size) == 0); + check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) != 0); +} + +static void __init test_prefix_word_alt_patching(void) +{ + extern unsigned int ftr_fixup_prefix3[]; + extern unsigned int end_ftr_fixup_prefix3[]; + extern unsigned int ftr_fixup_prefix3_orig[]; + extern unsigned int ftr_fixup_prefix3_expected[]; + extern unsigned int ftr_fixup_prefix3_alt[]; + int size = sizeof(unsigned int) * (end_ftr_fixup_prefix3 - ftr_fixup_prefix3); + + fixup.value = fixup.mask = 8; + fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix3 + 1); + fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix3 + 4); + fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix3_alt); + fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix3_alt + 3); + /* Sanity check */ + check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) == 0); + + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_expected, size) == 0); + patch_feature_section(0, &fixup); + check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) != 0); +} +#else +static inline void test_prefix_patching(void) {} +static inline void test_prefix_alt_patching(void) {} +static inline void test_prefix_word_alt_patching(void) {} +#endif /* CONFIG_PPC64 */ + +static int __init test_feature_fixups(void) +{ + printk(KERN_DEBUG "Running feature fixup self-tests ...\n"); + + test_basic_patching(); + test_alternative_patching(); + test_alternative_case_too_big(); + test_alternative_case_too_small(); + test_alternative_case_with_branch(); + test_alternative_case_with_external_branch(); + test_alternative_case_with_branch_to_end(); + test_cpu_macros(); + test_fw_macros(); + test_lwsync_macros(); + test_prefix_patching(); + test_prefix_alt_patching(); + test_prefix_word_alt_patching(); + + return 0; +} +late_initcall(test_feature_fixups); + +#endif /* CONFIG_FTR_FIXUP_SELFTEST */ |