diff options
Diffstat (limited to 'arch/arm/kernel')
-rw-r--r-- | arch/arm/kernel/Makefile | 6 | ||||
-rw-r--r-- | arch/arm/kernel/entry-armv.S | 19 | ||||
-rw-r--r-- | arch/arm/kernel/entry-header.S | 9 | ||||
-rw-r--r-- | arch/arm/kernel/ftrace.c | 50 | ||||
-rw-r--r-- | arch/arm/kernel/head-common.S | 1 | ||||
-rw-r--r-- | arch/arm/kernel/head.S | 6 | ||||
-rw-r--r-- | arch/arm/kernel/hw_breakpoint.c | 123 | ||||
-rw-r--r-- | arch/arm/kernel/insn.c | 19 | ||||
-rw-r--r-- | arch/arm/kernel/module-plts.c | 49 | ||||
-rw-r--r-- | arch/arm/kernel/ptrace.c | 4 | ||||
-rw-r--r-- | arch/arm/kernel/return_address.c | 4 | ||||
-rw-r--r-- | arch/arm/kernel/setup.c | 16 | ||||
-rw-r--r-- | arch/arm/kernel/signal.c | 14 | ||||
-rw-r--r-- | arch/arm/kernel/stacktrace.c | 23 | ||||
-rw-r--r-- | arch/arm/kernel/suspend.c | 19 |
15 files changed, 255 insertions, 107 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 50de918252b7..3939ad178405 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -17,10 +17,14 @@ CFLAGS_REMOVE_return_address.o = -pg # Object file lists. obj-y := elf.o entry-common.o irq.o opcodes.o \ - process.o ptrace.o reboot.o return_address.o \ + process.o ptrace.o reboot.o \ setup.o signal.o sigreturn_codes.o \ stacktrace.o sys_arm.o time.o traps.o +ifneq ($(CONFIG_ARM_UNWIND),y) +obj-$(CONFIG_FRAME_POINTER) += return_address.o +endif + obj-$(CONFIG_ATAGS) += atags_parse.o obj-$(CONFIG_ATAGS_PROC) += atags_proc.o obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += atags_compat.o diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index fbc707626b3e..2d8323648256 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -30,6 +30,7 @@ #include <asm/unistd.h> #include <asm/tls.h> #include <asm/system_info.h> +#include <asm/uaccess-asm.h> #include "entry-header.S" #include <asm/entry-macro-multi.S> @@ -186,15 +187,7 @@ ENDPROC(__und_invalid) stmia r7, {r2 - r6} get_thread_info tsk - ldr r0, [tsk, #TI_ADDR_LIMIT] - mov r1, #TASK_SIZE - str r1, [tsk, #TI_ADDR_LIMIT] - str r0, [sp, #SVC_ADDR_LIMIT] - - uaccess_save r0 - .if \uaccess - uaccess_disable r0 - .endif + uaccess_entry tsk, r0, r1, r2, \uaccess .if \trace #ifdef CONFIG_TRACE_IRQFLAGS @@ -631,11 +624,9 @@ call_fpe: tstne r0, #0x04000000 @ bit 26 set on both ARM and Thumb-2 reteq lr and r8, r0, #0x00000f00 @ mask out CP number - THUMB( lsr r8, r8, #8 ) mov r7, #1 - add r6, r10, #TI_USED_CP - ARM( strb r7, [r6, r8, lsr #8] ) @ set appropriate used_cp[] - THUMB( strb r7, [r6, r8] ) @ set appropriate used_cp[] + add r6, r10, r8, lsr #8 @ add used_cp[] array offset first + strb r7, [r6, #TI_USED_CP] @ set appropriate used_cp[] #ifdef CONFIG_IWMMXT @ Test if we need to give access to iWMMXt coprocessors ldr r5, [r10, #TI_FLAGS] @@ -644,7 +635,7 @@ call_fpe: bcs iwmmxt_task_enable #endif ARM( add pc, pc, r8, lsr #6 ) - THUMB( lsl r8, r8, #2 ) + THUMB( lsr r8, r8, #6 ) THUMB( add pc, r8 ) nop diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index 62db1c9746cb..7b595f2d4a28 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -6,6 +6,7 @@ #include <asm/asm-offsets.h> #include <asm/errno.h> #include <asm/thread_info.h> +#include <asm/uaccess-asm.h> #include <asm/v7m.h> @ Bad Abort numbers @@ -217,9 +218,7 @@ blne trace_hardirqs_off #endif .endif - ldr r1, [sp, #SVC_ADDR_LIMIT] - uaccess_restore - str r1, [tsk, #TI_ADDR_LIMIT] + uaccess_exit tsk, r0, r1 #ifndef CONFIG_THUMB2_KERNEL @ ARM mode SVC restore @@ -263,9 +262,7 @@ @ on the stack remains correct). @ .macro svc_exit_via_fiq - ldr r1, [sp, #SVC_ADDR_LIMIT] - uaccess_restore - str r1, [tsk, #TI_ADDR_LIMIT] + uaccess_exit tsk, r0, r1 #ifndef CONFIG_THUMB2_KERNEL @ ARM mode restore mov r0, sp diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index 5617932a83df..1a5edcfb0306 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -96,9 +96,10 @@ int ftrace_arch_code_modify_post_process(void) return 0; } -static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) +static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr, + bool warn) { - return arm_gen_branch_link(pc, addr); + return arm_gen_branch_link(pc, addr, warn); } static int ftrace_modify_code(unsigned long pc, unsigned long old, @@ -137,14 +138,14 @@ int ftrace_update_ftrace_func(ftrace_func_t func) int ret; pc = (unsigned long)&ftrace_call; - new = ftrace_call_replace(pc, (unsigned long)func); + new = ftrace_call_replace(pc, (unsigned long)func, true); ret = ftrace_modify_code(pc, 0, new, false); #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS if (!ret) { pc = (unsigned long)&ftrace_regs_call; - new = ftrace_call_replace(pc, (unsigned long)func); + new = ftrace_call_replace(pc, (unsigned long)func, true); ret = ftrace_modify_code(pc, 0, new, false); } @@ -153,7 +154,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) #ifdef CONFIG_OLD_MCOUNT if (!ret) { pc = (unsigned long)&ftrace_call_old; - new = ftrace_call_replace(pc, (unsigned long)func); + new = ftrace_call_replace(pc, (unsigned long)func, true); ret = ftrace_modify_code(pc, 0, new, false); } @@ -166,10 +167,22 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) { unsigned long new, old; unsigned long ip = rec->ip; + unsigned long aaddr = adjust_address(rec, addr); + struct module *mod = NULL; + +#ifdef CONFIG_ARM_MODULE_PLTS + mod = rec->arch.mod; +#endif old = ftrace_nop_replace(rec); - new = ftrace_call_replace(ip, adjust_address(rec, addr)); + new = ftrace_call_replace(ip, aaddr, !mod); +#ifdef CONFIG_ARM_MODULE_PLTS + if (!new && mod) { + aaddr = get_module_plt(mod, ip, aaddr); + new = ftrace_call_replace(ip, aaddr, true); + } +#endif return ftrace_modify_code(rec->ip, old, new, true); } @@ -182,9 +195,9 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, unsigned long new, old; unsigned long ip = rec->ip; - old = ftrace_call_replace(ip, adjust_address(rec, old_addr)); + old = ftrace_call_replace(ip, adjust_address(rec, old_addr), true); - new = ftrace_call_replace(ip, adjust_address(rec, addr)); + new = ftrace_call_replace(ip, adjust_address(rec, addr), true); return ftrace_modify_code(rec->ip, old, new, true); } @@ -194,12 +207,29 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr) { + unsigned long aaddr = adjust_address(rec, addr); unsigned long ip = rec->ip; unsigned long old; unsigned long new; int ret; - old = ftrace_call_replace(ip, adjust_address(rec, addr)); +#ifdef CONFIG_ARM_MODULE_PLTS + /* mod is only supplied during module loading */ + if (!mod) + mod = rec->arch.mod; + else + rec->arch.mod = mod; +#endif + + old = ftrace_call_replace(ip, aaddr, + !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod); +#ifdef CONFIG_ARM_MODULE_PLTS + if (!old && mod) { + aaddr = get_module_plt(mod, ip, aaddr); + old = ftrace_call_replace(ip, aaddr, true); + } +#endif + new = ftrace_nop_replace(rec); ret = ftrace_modify_code(ip, old, new, true); @@ -207,7 +237,7 @@ int ftrace_make_nop(struct module *mod, if (ret == -EINVAL && addr == MCOUNT_ADDR) { rec->arch.old_mcount = true; - old = ftrace_call_replace(ip, adjust_address(rec, addr)); + old = ftrace_call_replace(ip, adjust_address(rec, addr), true); new = ftrace_nop_replace(rec); ret = ftrace_modify_code(ip, old, new, true); } diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 7e662bdd5cb3..932b2244e709 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -101,6 +101,7 @@ __mmap_switched: str r2, [r6] @ Save atags pointer cmp r7, #0 strne r0, [r7] @ Save control register values + mov lr, #0 b start_kernel ENDPROC(__mmap_switched) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 6b1148cafffd..90add5ded3f1 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -675,11 +675,7 @@ ARM_BE8(rev16 ip, ip) bcc 1b bx lr #else -#ifdef CONFIG_CPU_ENDIAN_BE8 - moveq r0, #0x00004000 @ set bit 22, mov to mvn instruction -#else moveq r0, #0x400000 @ set bit 22, mov to mvn instruction -#endif b 2f 1: ldr ip, [r7, r3] #ifdef CONFIG_CPU_ENDIAN_BE8 @@ -688,7 +684,7 @@ ARM_BE8(rev16 ip, ip) tst ip, #0x000f0000 @ check the rotation field orrne ip, ip, r6, lsl #24 @ mask in offset bits 31-24 biceq ip, ip, #0x00004000 @ clear bit 22 - orreq ip, ip, r0 @ mask in offset bits 7-0 + orreq ip, ip, r0, ror #8 @ mask in offset bits 7-0 #else bic ip, ip, #0x000000ff tst ip, #0xf00 @ check the rotation field diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c index af2a7f1e3103..a8783964ebde 100644 --- a/arch/arm/kernel/hw_breakpoint.c +++ b/arch/arm/kernel/hw_breakpoint.c @@ -688,26 +688,68 @@ static void disable_single_step(struct perf_event *bp) arch_install_hw_breakpoint(bp); } +/* + * Arm32 hardware does not always report a watchpoint hit address that matches + * one of the watchpoints set. It can also report an address "near" the + * watchpoint if a single instruction access both watched and unwatched + * addresses. There is no straight-forward way, short of disassembling the + * offending instruction, to map that address back to the watchpoint. This + * function computes the distance of the memory access from the watchpoint as a + * heuristic for the likelyhood that a given access triggered the watchpoint. + * + * See this same function in the arm64 platform code, which has the same + * problem. + * + * The function returns the distance of the address from the bytes watched by + * the watchpoint. In case of an exact match, it returns 0. + */ +static u32 get_distance_from_watchpoint(unsigned long addr, u32 val, + struct arch_hw_breakpoint_ctrl *ctrl) +{ + u32 wp_low, wp_high; + u32 lens, lene; + + lens = __ffs(ctrl->len); + lene = __fls(ctrl->len); + + wp_low = val + lens; + wp_high = val + lene; + if (addr < wp_low) + return wp_low - addr; + else if (addr > wp_high) + return addr - wp_high; + else + return 0; +} + +static int watchpoint_fault_on_uaccess(struct pt_regs *regs, + struct arch_hw_breakpoint *info) +{ + return !user_mode(regs) && info->ctrl.privilege == ARM_BREAKPOINT_USER; +} + static void watchpoint_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { - int i, access; - u32 val, ctrl_reg, alignment_mask; + int i, access, closest_match = 0; + u32 min_dist = -1, dist; + u32 val, ctrl_reg; struct perf_event *wp, **slots; struct arch_hw_breakpoint *info; struct arch_hw_breakpoint_ctrl ctrl; slots = this_cpu_ptr(wp_on_reg); + /* + * Find all watchpoints that match the reported address. If no exact + * match is found. Attribute the hit to the closest watchpoint. + */ + rcu_read_lock(); for (i = 0; i < core_num_wrps; ++i) { - rcu_read_lock(); - wp = slots[i]; - if (wp == NULL) - goto unlock; + continue; - info = counter_arch_bp(wp); /* * The DFAR is an unknown value on debug architectures prior * to 7.1. Since we only allow a single watchpoint on these @@ -716,50 +758,69 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr, */ if (debug_arch < ARM_DEBUG_ARCH_V7_1) { BUG_ON(i > 0); + info = counter_arch_bp(wp); info->trigger = wp->attr.bp_addr; } else { - if (info->ctrl.len == ARM_BREAKPOINT_LEN_8) - alignment_mask = 0x7; - else - alignment_mask = 0x3; - - /* Check if the watchpoint value matches. */ - val = read_wb_reg(ARM_BASE_WVR + i); - if (val != (addr & ~alignment_mask)) - goto unlock; - - /* Possible match, check the byte address select. */ - ctrl_reg = read_wb_reg(ARM_BASE_WCR + i); - decode_ctrl_reg(ctrl_reg, &ctrl); - if (!((1 << (addr & alignment_mask)) & ctrl.len)) - goto unlock; - /* Check that the access type matches. */ if (debug_exception_updates_fsr()) { access = (fsr & ARM_FSR_ACCESS_MASK) ? HW_BREAKPOINT_W : HW_BREAKPOINT_R; if (!(access & hw_breakpoint_type(wp))) - goto unlock; + continue; } + val = read_wb_reg(ARM_BASE_WVR + i); + ctrl_reg = read_wb_reg(ARM_BASE_WCR + i); + decode_ctrl_reg(ctrl_reg, &ctrl); + dist = get_distance_from_watchpoint(addr, val, &ctrl); + if (dist < min_dist) { + min_dist = dist; + closest_match = i; + } + /* Is this an exact match? */ + if (dist != 0) + continue; + /* We have a winner. */ + info = counter_arch_bp(wp); info->trigger = addr; } pr_debug("watchpoint fired: address = 0x%x\n", info->trigger); + + /* + * If we triggered a user watchpoint from a uaccess routine, + * then handle the stepping ourselves since userspace really + * can't help us with this. + */ + if (watchpoint_fault_on_uaccess(regs, info)) + goto step; + perf_bp_event(wp, regs); /* - * If no overflow handler is present, insert a temporary - * mismatch breakpoint so we can single-step over the - * watchpoint trigger. + * Defer stepping to the overflow handler if one is installed. + * Otherwise, insert a temporary mismatch breakpoint so that + * we can single-step over the watchpoint trigger. */ + if (!is_default_overflow_handler(wp)) + continue; +step: + enable_single_step(wp, instruction_pointer(regs)); + } + + if (min_dist > 0 && min_dist != -1) { + /* No exact match found. */ + wp = slots[closest_match]; + info = counter_arch_bp(wp); + info->trigger = addr; + pr_debug("watchpoint fired: address = 0x%x\n", info->trigger); + perf_bp_event(wp, regs); if (is_default_overflow_handler(wp)) enable_single_step(wp, instruction_pointer(regs)); - -unlock: - rcu_read_unlock(); } + + rcu_read_unlock(); } static void watchpoint_single_step_handler(unsigned long pc) @@ -830,7 +891,7 @@ static void breakpoint_handler(unsigned long unknown, struct pt_regs *regs) info->trigger = addr; pr_debug("breakpoint fired: address = 0x%x\n", addr); perf_bp_event(bp, regs); - if (!bp->overflow_handler) + if (is_default_overflow_handler(bp)) enable_single_step(bp, addr); goto unlock; } diff --git a/arch/arm/kernel/insn.c b/arch/arm/kernel/insn.c index 2e844b70386b..db0acbb7d7a0 100644 --- a/arch/arm/kernel/insn.c +++ b/arch/arm/kernel/insn.c @@ -3,8 +3,9 @@ #include <linux/kernel.h> #include <asm/opcodes.h> -static unsigned long -__arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link) +static unsigned long __arm_gen_branch_thumb2(unsigned long pc, + unsigned long addr, bool link, + bool warn) { unsigned long s, j1, j2, i1, i2, imm10, imm11; unsigned long first, second; @@ -12,7 +13,7 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link) offset = (long)addr - (long)(pc + 4); if (offset < -16777216 || offset > 16777214) { - WARN_ON_ONCE(1); + WARN_ON_ONCE(warn); return 0; } @@ -33,8 +34,8 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link) return __opcode_thumb32_compose(first, second); } -static unsigned long -__arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link) +static unsigned long __arm_gen_branch_arm(unsigned long pc, unsigned long addr, + bool link, bool warn) { unsigned long opcode = 0xea000000; long offset; @@ -44,7 +45,7 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link) offset = (long)addr - (long)(pc + 8); if (unlikely(offset < -33554432 || offset > 33554428)) { - WARN_ON_ONCE(1); + WARN_ON_ONCE(warn); return 0; } @@ -54,10 +55,10 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link) } unsigned long -__arm_gen_branch(unsigned long pc, unsigned long addr, bool link) +__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn) { if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) - return __arm_gen_branch_thumb2(pc, addr, link); + return __arm_gen_branch_thumb2(pc, addr, link, warn); else - return __arm_gen_branch_arm(pc, addr, link); + return __arm_gen_branch_arm(pc, addr, link, warn); } diff --git a/arch/arm/kernel/module-plts.c b/arch/arm/kernel/module-plts.c index 3d0c2e4dda1d..ed0e09cc735f 100644 --- a/arch/arm/kernel/module-plts.c +++ b/arch/arm/kernel/module-plts.c @@ -7,6 +7,7 @@ */ #include <linux/elf.h> +#include <linux/ftrace.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/sort.h> @@ -14,10 +15,6 @@ #include <asm/cache.h> #include <asm/opcodes.h> -#define PLT_ENT_STRIDE L1_CACHE_BYTES -#define PLT_ENT_COUNT (PLT_ENT_STRIDE / sizeof(u32)) -#define PLT_ENT_SIZE (sizeof(struct plt_entries) / PLT_ENT_COUNT) - #ifdef CONFIG_THUMB2_KERNEL #define PLT_ENT_LDR __opcode_to_mem_thumb32(0xf8dff000 | \ (PLT_ENT_STRIDE - 4)) @@ -26,9 +23,11 @@ (PLT_ENT_STRIDE - 8)) #endif -struct plt_entries { - u32 ldr[PLT_ENT_COUNT]; - u32 lit[PLT_ENT_COUNT]; +static const u32 fixed_plts[] = { +#ifdef CONFIG_DYNAMIC_FTRACE + FTRACE_ADDR, + MCOUNT_ADDR, +#endif }; static bool in_init(const struct module *mod, unsigned long loc) @@ -36,14 +35,40 @@ static bool in_init(const struct module *mod, unsigned long loc) return loc - (u32)mod->init_layout.base < mod->init_layout.size; } +static void prealloc_fixed(struct mod_plt_sec *pltsec, struct plt_entries *plt) +{ + int i; + + if (!ARRAY_SIZE(fixed_plts) || pltsec->plt_count) + return; + pltsec->plt_count = ARRAY_SIZE(fixed_plts); + + for (i = 0; i < ARRAY_SIZE(plt->ldr); ++i) + plt->ldr[i] = PLT_ENT_LDR; + + BUILD_BUG_ON(sizeof(fixed_plts) > sizeof(plt->lit)); + memcpy(plt->lit, fixed_plts, sizeof(fixed_plts)); +} + u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val) { struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core : &mod->arch.init; + struct plt_entries *plt; + int idx; + + /* cache the address, ELF header is available only during module load */ + if (!pltsec->plt_ent) + pltsec->plt_ent = (struct plt_entries *)pltsec->plt->sh_addr; + plt = pltsec->plt_ent; - struct plt_entries *plt = (struct plt_entries *)pltsec->plt->sh_addr; - int idx = 0; + prealloc_fixed(pltsec, plt); + + for (idx = 0; idx < ARRAY_SIZE(fixed_plts); ++idx) + if (plt->lit[idx] == val) + return (u32)&plt->ldr[idx]; + idx = 0; /* * Look for an existing entry pointing to 'val'. Given that the * relocations are sorted, this will be the last entry we allocated. @@ -191,8 +216,8 @@ static unsigned int count_plts(const Elf32_Sym *syms, Elf32_Addr base, int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, char *secstrings, struct module *mod) { - unsigned long core_plts = 0; - unsigned long init_plts = 0; + unsigned long core_plts = ARRAY_SIZE(fixed_plts); + unsigned long init_plts = ARRAY_SIZE(fixed_plts); Elf32_Shdr *s, *sechdrs_end = sechdrs + ehdr->e_shnum; Elf32_Sym *syms = NULL; @@ -247,6 +272,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, mod->arch.core.plt->sh_size = round_up(core_plts * PLT_ENT_SIZE, sizeof(struct plt_entries)); mod->arch.core.plt_count = 0; + mod->arch.core.plt_ent = NULL; mod->arch.init.plt->sh_type = SHT_NOBITS; mod->arch.init.plt->sh_flags = SHF_EXECINSTR | SHF_ALLOC; @@ -254,6 +280,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, mod->arch.init.plt->sh_size = round_up(init_plts * PLT_ENT_SIZE, sizeof(struct plt_entries)); mod->arch.init.plt_count = 0; + mod->arch.init.plt_ent = NULL; pr_debug("%s: plt=%x, init.plt=%x\n", __func__, mod->arch.core.plt->sh_size, mod->arch.init.plt->sh_size); diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index 58e3771e4c5b..368b4b404985 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -228,8 +228,8 @@ static struct undef_hook arm_break_hook = { }; static struct undef_hook thumb_break_hook = { - .instr_mask = 0xffff, - .instr_val = 0xde01, + .instr_mask = 0xffffffff, + .instr_val = 0x0000de01, .cpsr_mask = PSR_T_BIT, .cpsr_val = PSR_T_BIT, .fn = break_trap, diff --git a/arch/arm/kernel/return_address.c b/arch/arm/kernel/return_address.c index 36ed35073289..f945742dea44 100644 --- a/arch/arm/kernel/return_address.c +++ b/arch/arm/kernel/return_address.c @@ -10,8 +10,6 @@ */ #include <linux/export.h> #include <linux/ftrace.h> - -#if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) #include <linux/sched.h> #include <asm/stacktrace.h> @@ -56,6 +54,4 @@ void *return_address(unsigned int level) return NULL; } -#endif /* if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND) */ - EXPORT_SYMBOL_GPL(return_address); diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index a6d27284105a..ac4ffd97ae82 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -547,9 +547,11 @@ void notrace cpu_init(void) * In Thumb-2, msr with an immediate value is not allowed. */ #ifdef CONFIG_THUMB2_KERNEL -#define PLC "r" +#define PLC_l "l" +#define PLC_r "r" #else -#define PLC "I" +#define PLC_l "I" +#define PLC_r "I" #endif /* @@ -571,15 +573,15 @@ void notrace cpu_init(void) "msr cpsr_c, %9" : : "r" (stk), - PLC (PSR_F_BIT | PSR_I_BIT | IRQ_MODE), + PLC_r (PSR_F_BIT | PSR_I_BIT | IRQ_MODE), "I" (offsetof(struct stack, irq[0])), - PLC (PSR_F_BIT | PSR_I_BIT | ABT_MODE), + PLC_r (PSR_F_BIT | PSR_I_BIT | ABT_MODE), "I" (offsetof(struct stack, abt[0])), - PLC (PSR_F_BIT | PSR_I_BIT | UND_MODE), + PLC_r (PSR_F_BIT | PSR_I_BIT | UND_MODE), "I" (offsetof(struct stack, und[0])), - PLC (PSR_F_BIT | PSR_I_BIT | FIQ_MODE), + PLC_r (PSR_F_BIT | PSR_I_BIT | FIQ_MODE), "I" (offsetof(struct stack, fiq[0])), - PLC (PSR_F_BIT | PSR_I_BIT | SVC_MODE) + PLC_l (PSR_F_BIT | PSR_I_BIT | SVC_MODE) : "r14"); #endif } diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 02e6b6dfffa7..19e4ff507209 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -667,18 +667,20 @@ struct page *get_signal_page(void) addr = page_address(page); + /* Poison the entire page */ + memset32(addr, __opcode_to_mem_arm(0xe7fddef1), + PAGE_SIZE / sizeof(u32)); + /* Give the signal return code some randomness */ offset = 0x200 + (get_random_int() & 0x7fc); signal_return_offset = offset; - /* - * Copy signal return handlers into the vector page, and - * set sigreturn to be a pointer to these. - */ + /* Copy signal return handlers into the page */ memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes)); - ptr = (unsigned long)addr + offset; - flush_icache_range(ptr, ptr + sizeof(sigreturn_codes)); + /* Flush out all instructions in this page */ + ptr = (unsigned long)addr; + flush_icache_range(ptr, ptr + PAGE_SIZE); return page; } diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index 65228bf4c6df..31af81d46aae 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -20,6 +20,19 @@ * A simple function epilogue looks like this: * ldm sp, {fp, sp, pc} * + * When compiled with clang, pc and sp are not pushed. A simple function + * prologue looks like this when built with clang: + * + * stmdb {..., fp, lr} + * add fp, sp, #x + * sub sp, sp, #y + * + * A simple function epilogue looks like this when built with clang: + * + * sub sp, fp, #x + * ldm {..., fp, pc} + * + * * Note that with framepointer enabled, even the leaf functions have the same * prologue and epilogue, therefore we can ignore the LR value in this case. */ @@ -32,6 +45,15 @@ int notrace unwind_frame(struct stackframe *frame) low = frame->sp; high = ALIGN(low, THREAD_SIZE); +#ifdef CONFIG_CC_IS_CLANG + /* check current frame pointer is within bounds */ + if (fp < low + 4 || fp > high - 4) + return -EINVAL; + + frame->sp = frame->fp; + frame->fp = *(unsigned long *)(fp); + frame->pc = *(unsigned long *)(fp + 4); +#else /* check current frame pointer is within bounds */ if (fp < low + 12 || fp > high - 4) return -EINVAL; @@ -40,6 +62,7 @@ int notrace unwind_frame(struct stackframe *frame) frame->fp = *(unsigned long *)(fp - 12); frame->sp = *(unsigned long *)(fp - 8); frame->pc = *(unsigned long *)(fp - 4); +#endif return 0; } diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c index d08099269e35..e126386fb78a 100644 --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include <linux/ftrace.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/mm_types.h> @@ -27,12 +28,22 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) return -EINVAL; /* + * Function graph tracer state gets incosistent when the kernel + * calls functions that never return (aka suspend finishers) hence + * disable graph tracing during their execution. + */ + pause_graph_tracing(); + + /* * Provide a temporary page table with an identity mapping for * the MMU-enable code, required for resuming. On successful * resume (indicated by a zero return code), we need to switch * back to the correct page tables. */ ret = __cpu_suspend(arg, fn, __mpidr); + + unpause_graph_tracing(); + if (ret == 0) { cpu_switch_mm(mm->pgd, mm); local_flush_bp_all(); @@ -46,7 +57,13 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) { u32 __mpidr = cpu_logical_map(smp_processor_id()); - return __cpu_suspend(arg, fn, __mpidr); + int ret; + + pause_graph_tracing(); + ret = __cpu_suspend(arg, fn, __mpidr); + unpause_graph_tracing(); + + return ret; } #define idmap_pgd NULL #endif |