diff options
Diffstat (limited to 'arch/arm64/kernel')
-rw-r--r-- | arch/arm64/kernel/alternative.c | 51 | ||||
-rw-r--r-- | arch/arm64/kernel/cpufeature.c | 4 | ||||
-rw-r--r-- | arch/arm64/kernel/hw_breakpoint.c | 86 | ||||
-rw-r--r-- | arch/arm64/kernel/irq.c | 10 | ||||
-rw-r--r-- | arch/arm64/kernel/module.c | 5 | ||||
-rw-r--r-- | arch/arm64/kernel/probes/kprobes.c | 88 |
6 files changed, 97 insertions, 147 deletions
diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 5c4bce4ac381..36fb069fd049 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -122,7 +122,30 @@ static void patch_alternative(struct alt_instr *alt, } } -static void __apply_alternatives(void *alt_region, bool use_linear_alias) +/* + * We provide our own, private D-cache cleaning function so that we don't + * accidentally call into the cache.S code, which is patched by us at + * runtime. + */ +static void clean_dcache_range_nopatch(u64 start, u64 end) +{ + u64 cur, d_size, ctr_el0; + + ctr_el0 = read_sanitised_ftr_reg(SYS_CTR_EL0); + d_size = 4 << cpuid_feature_extract_unsigned_field(ctr_el0, + CTR_DMINLINE_SHIFT); + cur = start & ~(d_size - 1); + do { + /* + * We must clean+invalidate to the PoC in order to avoid + * Cortex-A53 errata 826319, 827319, 824069 and 819472 + * (this corresponds to ARM64_WORKAROUND_CLEAN_CACHE) + */ + asm volatile("dc civac, %0" : : "r" (cur) : "memory"); + } while (cur += d_size, cur < end); +} + +static void __apply_alternatives(void *alt_region, bool is_module) { struct alt_instr *alt; struct alt_region *region = alt_region; @@ -145,7 +168,7 @@ static void __apply_alternatives(void *alt_region, bool use_linear_alias) pr_info_once("patching kernel code\n"); origptr = ALT_ORIG_PTR(alt); - updptr = use_linear_alias ? lm_alias(origptr) : origptr; + updptr = is_module ? origptr : lm_alias(origptr); nr_inst = alt->orig_len / AARCH64_INSN_SIZE; if (alt->cpufeature < ARM64_CB_PATCH) @@ -155,8 +178,20 @@ static void __apply_alternatives(void *alt_region, bool use_linear_alias) alt_cb(alt, origptr, updptr, nr_inst); - flush_icache_range((uintptr_t)origptr, - (uintptr_t)(origptr + nr_inst)); + if (!is_module) { + clean_dcache_range_nopatch((u64)origptr, + (u64)(origptr + nr_inst)); + } + } + + /* + * The core module code takes care of cache maintenance in + * flush_module_icache(). + */ + if (!is_module) { + dsb(ish); + __flush_icache_all(); + isb(); } } @@ -178,7 +213,7 @@ static int __apply_alternatives_multi_stop(void *unused) isb(); } else { BUG_ON(alternatives_applied); - __apply_alternatives(®ion, true); + __apply_alternatives(®ion, false); /* Barriers provided by the cache flushing */ WRITE_ONCE(alternatives_applied, 1); } @@ -192,12 +227,14 @@ void __init apply_alternatives_all(void) stop_machine(__apply_alternatives_multi_stop, NULL, cpu_online_mask); } -void apply_alternatives(void *start, size_t length) +#ifdef CONFIG_MODULES +void apply_alternatives_module(void *start, size_t length) { struct alt_region region = { .begin = start, .end = start + length, }; - __apply_alternatives(®ion, false); + __apply_alternatives(®ion, true); } +#endif diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index f24892a40d2c..c6d80743f4ed 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1351,9 +1351,9 @@ static void __update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, static void update_cpu_capabilities(u16 scope_mask) { - __update_cpu_capabilities(arm64_features, scope_mask, "detected:"); __update_cpu_capabilities(arm64_errata, scope_mask, "enabling workaround for"); + __update_cpu_capabilities(arm64_features, scope_mask, "detected:"); } static int __enable_cpu_capability(void *arg) @@ -1408,8 +1408,8 @@ __enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps, static void __init enable_cpu_capabilities(u16 scope_mask) { - __enable_cpu_capabilities(arm64_features, scope_mask); __enable_cpu_capabilities(arm64_errata, scope_mask); + __enable_cpu_capabilities(arm64_features, scope_mask); } /* diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 413dbe530da8..8c9644376326 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -343,14 +343,13 @@ static int get_hbp_len(u8 hbp_len) /* * Check whether bp virtual address is in kernel space. */ -int arch_check_bp_in_kernelspace(struct perf_event *bp) +int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw) { unsigned int len; unsigned long va; - struct arch_hw_breakpoint *info = counter_arch_bp(bp); - va = info->address; - len = get_hbp_len(info->ctrl.len); + va = hw->address; + len = get_hbp_len(hw->ctrl.len); return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE); } @@ -421,53 +420,53 @@ int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl, /* * Construct an arch_hw_breakpoint from a perf_event. */ -static int arch_build_bp_info(struct perf_event *bp) +static int arch_build_bp_info(struct perf_event *bp, + const struct perf_event_attr *attr, + struct arch_hw_breakpoint *hw) { - struct arch_hw_breakpoint *info = counter_arch_bp(bp); - /* Type */ - switch (bp->attr.bp_type) { + switch (attr->bp_type) { case HW_BREAKPOINT_X: - info->ctrl.type = ARM_BREAKPOINT_EXECUTE; + hw->ctrl.type = ARM_BREAKPOINT_EXECUTE; break; case HW_BREAKPOINT_R: - info->ctrl.type = ARM_BREAKPOINT_LOAD; + hw->ctrl.type = ARM_BREAKPOINT_LOAD; break; case HW_BREAKPOINT_W: - info->ctrl.type = ARM_BREAKPOINT_STORE; + hw->ctrl.type = ARM_BREAKPOINT_STORE; break; case HW_BREAKPOINT_RW: - info->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE; + hw->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE; break; default: return -EINVAL; } /* Len */ - switch (bp->attr.bp_len) { + switch (attr->bp_len) { case HW_BREAKPOINT_LEN_1: - info->ctrl.len = ARM_BREAKPOINT_LEN_1; + hw->ctrl.len = ARM_BREAKPOINT_LEN_1; break; case HW_BREAKPOINT_LEN_2: - info->ctrl.len = ARM_BREAKPOINT_LEN_2; + hw->ctrl.len = ARM_BREAKPOINT_LEN_2; break; case HW_BREAKPOINT_LEN_3: - info->ctrl.len = ARM_BREAKPOINT_LEN_3; + hw->ctrl.len = ARM_BREAKPOINT_LEN_3; break; case HW_BREAKPOINT_LEN_4: - info->ctrl.len = ARM_BREAKPOINT_LEN_4; + hw->ctrl.len = ARM_BREAKPOINT_LEN_4; break; case HW_BREAKPOINT_LEN_5: - info->ctrl.len = ARM_BREAKPOINT_LEN_5; + hw->ctrl.len = ARM_BREAKPOINT_LEN_5; break; case HW_BREAKPOINT_LEN_6: - info->ctrl.len = ARM_BREAKPOINT_LEN_6; + hw->ctrl.len = ARM_BREAKPOINT_LEN_6; break; case HW_BREAKPOINT_LEN_7: - info->ctrl.len = ARM_BREAKPOINT_LEN_7; + hw->ctrl.len = ARM_BREAKPOINT_LEN_7; break; case HW_BREAKPOINT_LEN_8: - info->ctrl.len = ARM_BREAKPOINT_LEN_8; + hw->ctrl.len = ARM_BREAKPOINT_LEN_8; break; default: return -EINVAL; @@ -478,37 +477,37 @@ static int arch_build_bp_info(struct perf_event *bp) * AArch32 also requires breakpoints of length 2 for Thumb. * Watchpoints can be of length 1, 2, 4 or 8 bytes. */ - if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) { + if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE) { if (is_compat_bp(bp)) { - if (info->ctrl.len != ARM_BREAKPOINT_LEN_2 && - info->ctrl.len != ARM_BREAKPOINT_LEN_4) + if (hw->ctrl.len != ARM_BREAKPOINT_LEN_2 && + hw->ctrl.len != ARM_BREAKPOINT_LEN_4) return -EINVAL; - } else if (info->ctrl.len != ARM_BREAKPOINT_LEN_4) { + } else if (hw->ctrl.len != ARM_BREAKPOINT_LEN_4) { /* * FIXME: Some tools (I'm looking at you perf) assume * that breakpoints should be sizeof(long). This * is nonsense. For now, we fix up the parameter * but we should probably return -EINVAL instead. */ - info->ctrl.len = ARM_BREAKPOINT_LEN_4; + hw->ctrl.len = ARM_BREAKPOINT_LEN_4; } } /* Address */ - info->address = bp->attr.bp_addr; + hw->address = attr->bp_addr; /* * Privilege * Note that we disallow combined EL0/EL1 breakpoints because * that would complicate the stepping code. */ - if (arch_check_bp_in_kernelspace(bp)) - info->ctrl.privilege = AARCH64_BREAKPOINT_EL1; + if (arch_check_bp_in_kernelspace(hw)) + hw->ctrl.privilege = AARCH64_BREAKPOINT_EL1; else - info->ctrl.privilege = AARCH64_BREAKPOINT_EL0; + hw->ctrl.privilege = AARCH64_BREAKPOINT_EL0; /* Enabled? */ - info->ctrl.enabled = !bp->attr.disabled; + hw->ctrl.enabled = !attr->disabled; return 0; } @@ -516,14 +515,15 @@ static int arch_build_bp_info(struct perf_event *bp) /* * Validate the arch-specific HW Breakpoint register settings. */ -int arch_validate_hwbkpt_settings(struct perf_event *bp) +int hw_breakpoint_arch_parse(struct perf_event *bp, + const struct perf_event_attr *attr, + struct arch_hw_breakpoint *hw) { - struct arch_hw_breakpoint *info = counter_arch_bp(bp); int ret; u64 alignment_mask, offset; /* Build the arch_hw_breakpoint. */ - ret = arch_build_bp_info(bp); + ret = arch_build_bp_info(bp, attr, hw); if (ret) return ret; @@ -537,42 +537,42 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp) * that here. */ if (is_compat_bp(bp)) { - if (info->ctrl.len == ARM_BREAKPOINT_LEN_8) + if (hw->ctrl.len == ARM_BREAKPOINT_LEN_8) alignment_mask = 0x7; else alignment_mask = 0x3; - offset = info->address & alignment_mask; + offset = hw->address & alignment_mask; switch (offset) { case 0: /* Aligned */ break; case 1: /* Allow single byte watchpoint. */ - if (info->ctrl.len == ARM_BREAKPOINT_LEN_1) + if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) break; case 2: /* Allow halfword watchpoints and breakpoints. */ - if (info->ctrl.len == ARM_BREAKPOINT_LEN_2) + if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) break; default: return -EINVAL; } } else { - if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) + if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE) alignment_mask = 0x3; else alignment_mask = 0x7; - offset = info->address & alignment_mask; + offset = hw->address & alignment_mask; } - info->address &= ~alignment_mask; - info->ctrl.len <<= offset; + hw->address &= ~alignment_mask; + hw->ctrl.len <<= offset; /* * Disallow per-task kernel breakpoints since these would * complicate the stepping code. */ - if (info->ctrl.privilege == AARCH64_BREAKPOINT_EL1 && bp->hw.target) + if (hw->ctrl.privilege == AARCH64_BREAKPOINT_EL1 && bp->hw.target) return -EINVAL; return 0; diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c index 60e5fc661f74..780a12f59a8f 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -42,16 +42,6 @@ int arch_show_interrupts(struct seq_file *p, int prec) return 0; } -void (*handle_arch_irq)(struct pt_regs *) = NULL; - -void __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) -{ - if (handle_arch_irq) - return; - - handle_arch_irq = handle_irq; -} - #ifdef CONFIG_VMAP_STACK static void init_irq_stacks(void) { diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index 155fd91e78f4..f0f27aeefb73 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -448,9 +448,8 @@ int module_finalize(const Elf_Ehdr *hdr, const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) { - if (strcmp(".altinstructions", secstrs + s->sh_name) == 0) { - apply_alternatives((void *)s->sh_addr, s->sh_size); - } + if (strcmp(".altinstructions", secstrs + s->sh_name) == 0) + apply_alternatives_module((void *)s->sh_addr, s->sh_size); #ifdef CONFIG_ARM64_MODULE_PLTS if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE) && !strcmp(".text.ftrace_trampoline", secstrs + s->sh_name)) diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index d849d9804011..e78c3ef04d95 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -275,7 +275,7 @@ static int __kprobes reenter_kprobe(struct kprobe *p, break; case KPROBE_HIT_SS: case KPROBE_REENTER: - pr_warn("Unrecoverable kprobe detected at %p.\n", p->addr); + pr_warn("Unrecoverable kprobe detected.\n"); dump_kprobe(p); BUG(); break; @@ -395,9 +395,9 @@ static void __kprobes kprobe_handler(struct pt_regs *regs) /* * If we have no pre-handler or it returned 0, we * continue with normal processing. If we have a - * pre-handler and it returned non-zero, it prepped - * for calling the break_handler below on re-entry, - * so get out doing nothing more here. + * pre-handler and it returned non-zero, it will + * modify the execution path and no need to single + * stepping. Let's just reset current kprobe and exit. * * pre_handler can hit a breakpoint and can step thru * before return, keep PSTATE D-flag enabled until @@ -405,16 +405,8 @@ static void __kprobes kprobe_handler(struct pt_regs *regs) */ if (!p->pre_handler || !p->pre_handler(p, regs)) { setup_singlestep(p, regs, kcb, 0); - return; - } - } - } else if ((le32_to_cpu(*(kprobe_opcode_t *) addr) == - BRK64_OPCODE_KPROBES) && cur_kprobe) { - /* We probably hit a jprobe. Call its break handler. */ - if (cur_kprobe->break_handler && - cur_kprobe->break_handler(cur_kprobe, regs)) { - setup_singlestep(cur_kprobe, regs, kcb, 0); - return; + } else + reset_current_kprobe(); } } /* @@ -465,74 +457,6 @@ kprobe_breakpoint_handler(struct pt_regs *regs, unsigned int esr) return DBG_HOOK_HANDLED; } -int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct jprobe *jp = container_of(p, struct jprobe, kp); - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - - kcb->jprobe_saved_regs = *regs; - /* - * Since we can't be sure where in the stack frame "stacked" - * pass-by-value arguments are stored we just don't try to - * duplicate any of the stack. Do not use jprobes on functions that - * use more than 64 bytes (after padding each to an 8 byte boundary) - * of arguments, or pass individual arguments larger than 16 bytes. - */ - - instruction_pointer_set(regs, (unsigned long) jp->entry); - preempt_disable(); - pause_graph_tracing(); - return 1; -} - -void __kprobes jprobe_return(void) -{ - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - - /* - * Jprobe handler return by entering break exception, - * encoded same as kprobe, but with following conditions - * -a special PC to identify it from the other kprobes. - * -restore stack addr to original saved pt_regs - */ - asm volatile(" mov sp, %0 \n" - "jprobe_return_break: brk %1 \n" - : - : "r" (kcb->jprobe_saved_regs.sp), - "I" (BRK64_ESR_KPROBES) - : "memory"); - - unreachable(); -} - -int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) -{ - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - long stack_addr = kcb->jprobe_saved_regs.sp; - long orig_sp = kernel_stack_pointer(regs); - struct jprobe *jp = container_of(p, struct jprobe, kp); - extern const char jprobe_return_break[]; - - if (instruction_pointer(regs) != (u64) jprobe_return_break) - return 0; - - if (orig_sp != stack_addr) { - struct pt_regs *saved_regs = - (struct pt_regs *)kcb->jprobe_saved_regs.sp; - pr_err("current sp %lx does not match saved sp %lx\n", - orig_sp, stack_addr); - pr_err("Saved registers for jprobe %p\n", jp); - __show_regs(saved_regs); - pr_err("Current registers\n"); - __show_regs(regs); - BUG(); - } - unpause_graph_tracing(); - *regs = kcb->jprobe_saved_regs; - preempt_enable_no_resched(); - return 1; -} - bool arch_within_kprobe_blacklist(unsigned long addr) { if ((addr >= (unsigned long)__kprobes_text_start && |