diff options
Diffstat (limited to 'arch/loongarch/kernel')
| -rw-r--r-- | arch/loongarch/kernel/Makefile | 4 | ||||
| -rw-r--r-- | arch/loongarch/kernel/entry.S | 5 | ||||
| -rw-r--r-- | arch/loongarch/kernel/fpu.S | 7 | ||||
| -rw-r--r-- | arch/loongarch/kernel/genex.S | 6 | ||||
| -rw-r--r-- | arch/loongarch/kernel/lbt.S | 3 | ||||
| -rw-r--r-- | arch/loongarch/kernel/mcount_dyn.S | 6 | ||||
| -rw-r--r-- | arch/loongarch/kernel/module.c | 22 | ||||
| -rw-r--r-- | arch/loongarch/kernel/relocate_kernel.S | 7 | ||||
| -rw-r--r-- | arch/loongarch/kernel/rethook_trampoline.S | 1 | ||||
| -rw-r--r-- | arch/loongarch/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/loongarch/kernel/stacktrace.c | 41 | ||||
| -rw-r--r-- | arch/loongarch/kernel/traps.c | 42 | ||||
| -rw-r--r-- | arch/loongarch/kernel/unwind_orc.c | 528 | ||||
| -rw-r--r-- | arch/loongarch/kernel/vmlinux.lds.S | 3 |
14 files changed, 657 insertions, 20 deletions
diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index 3c808c6803703c..3a7620b66bc6c0 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -3,6 +3,8 @@ # Makefile for the Linux/LoongArch kernel. # +OBJECT_FILES_NON_STANDARD_head.o := y + extra-y := vmlinux.lds obj-y += head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \ @@ -21,6 +23,7 @@ obj-$(CONFIG_ARCH_STRICT_ALIGN) += unaligned.o CFLAGS_module.o += $(call cc-option,-Wno-override-init,) CFLAGS_syscall.o += $(call cc-option,-Wno-override-init,) +CFLAGS_traps.o += $(call cc-option,-Wno-override-init,) CFLAGS_perf_event.o += $(call cc-option,-Wno-override-init,) ifdef CONFIG_FUNCTION_TRACER @@ -62,6 +65,7 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o obj-$(CONFIG_UNWINDER_PROLOGUE) += unwind_prologue.o +obj-$(CONFIG_UNWINDER_ORC) += unwind_orc.o obj-$(CONFIG_PERF_EVENTS) += perf_event.o perf_regs.o obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o diff --git a/arch/loongarch/kernel/entry.S b/arch/loongarch/kernel/entry.S index 1ec8e4c4cc2bd8..48e7e34e355e83 100644 --- a/arch/loongarch/kernel/entry.S +++ b/arch/loongarch/kernel/entry.S @@ -14,11 +14,13 @@ #include <asm/regdef.h> #include <asm/stackframe.h> #include <asm/thread_info.h> +#include <asm/unwind_hints.h> .text .cfi_sections .debug_frame .align 5 SYM_CODE_START(handle_syscall) + UNWIND_HINT_UNDEFINED csrrd t0, PERCPU_BASE_KS la.pcrel t1, kernelsp add.d t1, t1, t0 @@ -57,6 +59,7 @@ SYM_CODE_START(handle_syscall) cfi_st fp, PT_R22 SAVE_STATIC + UNWIND_HINT_REGS #ifdef CONFIG_KGDB li.w t1, CSR_CRMD_WE @@ -75,6 +78,7 @@ SYM_CODE_END(handle_syscall) _ASM_NOKPROBE(handle_syscall) SYM_CODE_START(ret_from_fork) + UNWIND_HINT_REGS bl schedule_tail # a0 = struct task_struct *prev move a0, sp bl syscall_exit_to_user_mode @@ -84,6 +88,7 @@ SYM_CODE_START(ret_from_fork) SYM_CODE_END(ret_from_fork) SYM_CODE_START(ret_from_kernel_thread) + UNWIND_HINT_REGS bl schedule_tail # a0 = struct task_struct *prev move a0, s1 jirl ra, s0, 0 diff --git a/arch/loongarch/kernel/fpu.S b/arch/loongarch/kernel/fpu.S index 4382e36ae3d444..69a85f2479fba1 100644 --- a/arch/loongarch/kernel/fpu.S +++ b/arch/loongarch/kernel/fpu.S @@ -15,6 +15,7 @@ #include <asm/fpregdef.h> #include <asm/loongarch.h> #include <asm/regdef.h> +#include <asm/unwind_hints.h> #define FPU_REG_WIDTH 8 #define LSX_REG_WIDTH 16 @@ -526,3 +527,9 @@ SYM_FUNC_END(_restore_lasx_context) .L_fpu_fault: li.w a0, -EFAULT # failure jr ra + +#ifdef CONFIG_CPU_HAS_LBT +STACK_FRAME_NON_STANDARD _restore_fp +STACK_FRAME_NON_STANDARD _restore_lsx +STACK_FRAME_NON_STANDARD _restore_lasx +#endif diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S index 2bb3aa2dcfcb2e..86d5d90ebefe5b 100644 --- a/arch/loongarch/kernel/genex.S +++ b/arch/loongarch/kernel/genex.S @@ -32,6 +32,7 @@ SYM_FUNC_START(__arch_cpu_idle) SYM_FUNC_END(__arch_cpu_idle) SYM_CODE_START(handle_vint) + UNWIND_HINT_UNDEFINED BACKUP_T0T1 SAVE_ALL la_abs t1, __arch_cpu_idle @@ -49,6 +50,7 @@ SYM_CODE_START(handle_vint) SYM_CODE_END(handle_vint) SYM_CODE_START(except_vec_cex) + UNWIND_HINT_UNDEFINED b cache_parity_error SYM_CODE_END(except_vec_cex) @@ -67,6 +69,7 @@ SYM_CODE_END(except_vec_cex) .macro BUILD_HANDLER exception handler prep .align 5 SYM_CODE_START(handle_\exception) + UNWIND_HINT_UNDEFINED 666: BACKUP_T0T1 SAVE_ALL @@ -77,7 +80,9 @@ SYM_CODE_END(except_vec_cex) 668: RESTORE_ALL_AND_RET SYM_CODE_END(handle_\exception) + .pushsection ".data", "aw", %progbits SYM_DATA(unwind_hint_\exception, .word 668b - 666b) + .popsection .endm BUILD_HANDLER ade ade badv @@ -94,6 +99,7 @@ SYM_CODE_END(except_vec_cex) BUILD_HANDLER reserved reserved none /* others */ SYM_CODE_START(handle_sys) + UNWIND_HINT_UNDEFINED la_abs t0, handle_syscall jr t0 SYM_CODE_END(handle_sys) diff --git a/arch/loongarch/kernel/lbt.S b/arch/loongarch/kernel/lbt.S index 9c75120a26d836..001f061d226ab5 100644 --- a/arch/loongarch/kernel/lbt.S +++ b/arch/loongarch/kernel/lbt.S @@ -11,6 +11,7 @@ #include <asm/asm-offsets.h> #include <asm/errno.h> #include <asm/regdef.h> +#include <asm/unwind_hints.h> #define SCR_REG_WIDTH 8 @@ -153,3 +154,5 @@ SYM_FUNC_END(_restore_ftop_context) .L_lbt_fault: li.w a0, -EFAULT # failure jr ra + +STACK_FRAME_NON_STANDARD _restore_ftop_context diff --git a/arch/loongarch/kernel/mcount_dyn.S b/arch/loongarch/kernel/mcount_dyn.S index 482aa553aa2d5e..0c65cf09110cd4 100644 --- a/arch/loongarch/kernel/mcount_dyn.S +++ b/arch/loongarch/kernel/mcount_dyn.S @@ -73,6 +73,7 @@ SYM_FUNC_START(ftrace_stub) SYM_FUNC_END(ftrace_stub) SYM_CODE_START(ftrace_common) + UNWIND_HINT_UNDEFINED PTR_ADDI a0, ra, -8 /* arg0: ip */ move a1, t0 /* arg1: parent_ip */ la.pcrel t1, function_trace_op @@ -113,12 +114,14 @@ ftrace_common_return: SYM_CODE_END(ftrace_common) SYM_CODE_START(ftrace_caller) + UNWIND_HINT_UNDEFINED ftrace_regs_entry allregs=0 b ftrace_common SYM_CODE_END(ftrace_caller) #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS SYM_CODE_START(ftrace_regs_caller) + UNWIND_HINT_UNDEFINED ftrace_regs_entry allregs=1 b ftrace_common SYM_CODE_END(ftrace_regs_caller) @@ -126,6 +129,7 @@ SYM_CODE_END(ftrace_regs_caller) #ifdef CONFIG_FUNCTION_GRAPH_TRACER SYM_CODE_START(ftrace_graph_caller) + UNWIND_HINT_UNDEFINED PTR_L a0, sp, PT_ERA PTR_ADDI a0, a0, -8 /* arg0: self_addr */ PTR_ADDI a1, sp, PT_R1 /* arg1: parent */ @@ -134,6 +138,7 @@ SYM_CODE_START(ftrace_graph_caller) SYM_CODE_END(ftrace_graph_caller) SYM_CODE_START(return_to_handler) + UNWIND_HINT_UNDEFINED /* Save return value regs */ PTR_ADDI sp, sp, -FGRET_REGS_SIZE PTR_S a0, sp, FGRET_REGS_A0 @@ -155,6 +160,7 @@ SYM_CODE_END(return_to_handler) #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS SYM_CODE_START(ftrace_stub_direct_tramp) + UNWIND_HINT_UNDEFINED jr t0 SYM_CODE_END(ftrace_stub_direct_tramp) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ diff --git a/arch/loongarch/kernel/module.c b/arch/loongarch/kernel/module.c index b13b2858fe3923..c7d0338d12c15b 100644 --- a/arch/loongarch/kernel/module.c +++ b/arch/loongarch/kernel/module.c @@ -20,6 +20,7 @@ #include <linux/kernel.h> #include <asm/alternative.h> #include <asm/inst.h> +#include <asm/unwind.h> static int rela_stack_push(s64 stack_value, s64 *rela_stack, size_t *rela_stack_top) { @@ -515,15 +516,28 @@ static void module_init_ftrace_plt(const Elf_Ehdr *hdr, int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *mod) { - const Elf_Shdr *s, *se; const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + const Elf_Shdr *s, *alt = NULL, *orc = NULL, *orc_ip = NULL, *ftrace = NULL; - for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) { + for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { if (!strcmp(".altinstructions", secstrs + s->sh_name)) - apply_alternatives((void *)s->sh_addr, (void *)s->sh_addr + s->sh_size); + alt = s; + if (!strcmp(".orc_unwind", secstrs + s->sh_name)) + orc = s; + if (!strcmp(".orc_unwind_ip", secstrs + s->sh_name)) + orc_ip = s; if (!strcmp(".ftrace_trampoline", secstrs + s->sh_name)) - module_init_ftrace_plt(hdr, s, mod); + ftrace = s; } + if (alt) + apply_alternatives((void *)alt->sh_addr, (void *)alt->sh_addr + alt->sh_size); + + if (orc && orc_ip) + unwind_module_init(mod, (void *)orc_ip->sh_addr, orc_ip->sh_size, (void *)orc->sh_addr, orc->sh_size); + + if (ftrace) + module_init_ftrace_plt(hdr, ftrace, mod); + return 0; } diff --git a/arch/loongarch/kernel/relocate_kernel.S b/arch/loongarch/kernel/relocate_kernel.S index f49f6b053763d1..84e6de2fd97354 100644 --- a/arch/loongarch/kernel/relocate_kernel.S +++ b/arch/loongarch/kernel/relocate_kernel.S @@ -15,6 +15,7 @@ #include <asm/addrspace.h> SYM_CODE_START(relocate_new_kernel) + UNWIND_HINT_UNDEFINED /* * a0: EFI boot flag for the new kernel * a1: Command line pointer for the new kernel @@ -90,6 +91,7 @@ SYM_CODE_END(relocate_new_kernel) * then start at the entry point from LOONGARCH_IOCSR_MBUF0. */ SYM_CODE_START(kexec_smp_wait) + UNWIND_HINT_UNDEFINED 1: li.w t0, 0x100 /* wait for init loop */ 2: addi.w t0, t0, -1 /* limit mailbox access */ bnez t0, 2b @@ -106,6 +108,5 @@ SYM_CODE_END(kexec_smp_wait) relocate_new_kernel_end: -SYM_DATA_START(relocate_new_kernel_size) - PTR relocate_new_kernel_end - relocate_new_kernel -SYM_DATA_END(relocate_new_kernel_size) + .section ".data" +SYM_DATA(relocate_new_kernel_size, .long relocate_new_kernel_end - relocate_new_kernel) diff --git a/arch/loongarch/kernel/rethook_trampoline.S b/arch/loongarch/kernel/rethook_trampoline.S index bd5772c963382f..d4ceb2fa2a5ce4 100644 --- a/arch/loongarch/kernel/rethook_trampoline.S +++ b/arch/loongarch/kernel/rethook_trampoline.S @@ -76,6 +76,7 @@ .endm SYM_CODE_START(arch_rethook_trampoline) + UNWIND_HINT_UNDEFINED addi.d sp, sp, -PT_SIZE save_all_base_regs diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c index 2b72eb326b4428..60e0fe97f61a31 100644 --- a/arch/loongarch/kernel/setup.c +++ b/arch/loongarch/kernel/setup.c @@ -47,6 +47,7 @@ #include <asm/sections.h> #include <asm/setup.h> #include <asm/time.h> +#include <asm/unwind.h> #define SMBIOS_BIOSSIZE_OFFSET 0x09 #define SMBIOS_BIOSEXTERN_OFFSET 0x13 @@ -587,6 +588,7 @@ static void __init prefill_possible_map(void) void __init setup_arch(char **cmdline_p) { cpu_probe(); + unwind_init(); init_environ(); efi_init(); diff --git a/arch/loongarch/kernel/stacktrace.c b/arch/loongarch/kernel/stacktrace.c index f623feb2129f12..9a038d1070d73b 100644 --- a/arch/loongarch/kernel/stacktrace.c +++ b/arch/loongarch/kernel/stacktrace.c @@ -29,6 +29,7 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, regs->csr_era = thread_saved_ra(task); } regs->regs[1] = 0; + regs->regs[22] = 0; } for (unwind_start(&state, task, regs); @@ -39,6 +40,46 @@ void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, } } +int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, + void *cookie, struct task_struct *task) +{ + unsigned long addr; + struct pt_regs dummyregs; + struct pt_regs *regs = &dummyregs; + struct unwind_state state; + + if (task == current) { + regs->regs[3] = (unsigned long)__builtin_frame_address(0); + regs->csr_era = (unsigned long)__builtin_return_address(0); + } else { + regs->regs[3] = thread_saved_fp(task); + regs->csr_era = thread_saved_ra(task); + } + regs->regs[1] = 0; + regs->regs[22] = 0; + + for (unwind_start(&state, task, regs); + !unwind_done(&state) && !unwind_error(&state); unwind_next_frame(&state)) { + addr = unwind_get_return_address(&state); + + /* + * A NULL or invalid return address probably means there's some + * generated code which __kernel_text_address() doesn't know about. + */ + if (!addr) + return -EINVAL; + + if (!consume_entry(cookie, addr)) + return -EINVAL; + } + + /* Check for stack corruption */ + if (unwind_error(&state)) + return -EINVAL; + + return 0; +} + static int copy_stack_frame(unsigned long fp, struct stack_frame *frame) { diff --git a/arch/loongarch/kernel/traps.c b/arch/loongarch/kernel/traps.c index aebfc3733a7607..f9f4eb00c92ef5 100644 --- a/arch/loongarch/kernel/traps.c +++ b/arch/loongarch/kernel/traps.c @@ -53,6 +53,32 @@ #include "access-helper.h" +void *exception_table[EXCCODE_INT_START] = { + [0 ... EXCCODE_INT_START - 1] = handle_reserved, + + [EXCCODE_TLBI] = handle_tlb_load, + [EXCCODE_TLBL] = handle_tlb_load, + [EXCCODE_TLBS] = handle_tlb_store, + [EXCCODE_TLBM] = handle_tlb_modify, + [EXCCODE_TLBNR] = handle_tlb_protect, + [EXCCODE_TLBNX] = handle_tlb_protect, + [EXCCODE_TLBPE] = handle_tlb_protect, + [EXCCODE_ADE] = handle_ade, + [EXCCODE_ALE] = handle_ale, + [EXCCODE_BCE] = handle_bce, + [EXCCODE_SYS] = handle_sys, + [EXCCODE_BP] = handle_bp, + [EXCCODE_INE] = handle_ri, + [EXCCODE_IPE] = handle_ri, + [EXCCODE_FPDIS] = handle_fpu, + [EXCCODE_LSXDIS] = handle_lsx, + [EXCCODE_LASXDIS] = handle_lasx, + [EXCCODE_FPE] = handle_fpe, + [EXCCODE_WATCH] = handle_watch, + [EXCCODE_BTDIS] = handle_lbt, +}; +EXPORT_SYMBOL_GPL(exception_table); + static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, const char *loglvl, bool user) { @@ -1150,19 +1176,9 @@ void __init trap_init(void) for (i = EXCCODE_INT_START; i <= EXCCODE_INT_END; i++) set_handler(i * VECSIZE, handle_vint, VECSIZE); - set_handler(EXCCODE_ADE * VECSIZE, handle_ade, VECSIZE); - set_handler(EXCCODE_ALE * VECSIZE, handle_ale, VECSIZE); - set_handler(EXCCODE_BCE * VECSIZE, handle_bce, VECSIZE); - set_handler(EXCCODE_SYS * VECSIZE, handle_sys, VECSIZE); - set_handler(EXCCODE_BP * VECSIZE, handle_bp, VECSIZE); - set_handler(EXCCODE_INE * VECSIZE, handle_ri, VECSIZE); - set_handler(EXCCODE_IPE * VECSIZE, handle_ri, VECSIZE); - set_handler(EXCCODE_FPDIS * VECSIZE, handle_fpu, VECSIZE); - set_handler(EXCCODE_LSXDIS * VECSIZE, handle_lsx, VECSIZE); - set_handler(EXCCODE_LASXDIS * VECSIZE, handle_lasx, VECSIZE); - set_handler(EXCCODE_FPE * VECSIZE, handle_fpe, VECSIZE); - set_handler(EXCCODE_BTDIS * VECSIZE, handle_lbt, VECSIZE); - set_handler(EXCCODE_WATCH * VECSIZE, handle_watch, VECSIZE); + /* Set exception vector handler */ + for (i = EXCCODE_ADE; i <= EXCCODE_BTDIS; i++) + set_handler(i * VECSIZE, exception_table[i], VECSIZE); cache_error_setup(); diff --git a/arch/loongarch/kernel/unwind_orc.c b/arch/loongarch/kernel/unwind_orc.c new file mode 100644 index 00000000000000..b2572287633179 --- /dev/null +++ b/arch/loongarch/kernel/unwind_orc.c @@ -0,0 +1,528 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/objtool.h> +#include <linux/module.h> +#include <linux/sort.h> +#include <asm/exception.h> +#include <asm/orc_header.h> +#include <asm/orc_lookup.h> +#include <asm/orc_types.h> +#include <asm/ptrace.h> +#include <asm/setup.h> +#include <asm/stacktrace.h> +#include <asm/tlb.h> +#include <asm/unwind.h> + +ORC_HEADER; + +#define orc_warn(fmt, ...) \ + printk_deferred_once(KERN_WARNING "WARNING: " fmt, ##__VA_ARGS__) + +extern int __start_orc_unwind_ip[]; +extern int __stop_orc_unwind_ip[]; +extern struct orc_entry __start_orc_unwind[]; +extern struct orc_entry __stop_orc_unwind[]; + +static bool orc_init __ro_after_init; +static unsigned int lookup_num_blocks __ro_after_init; + +/* Fake frame pointer entry -- used as a fallback for generated code */ +static struct orc_entry orc_fp_entry = { + .sp_reg = ORC_REG_FP, + .sp_offset = 16, + .fp_reg = ORC_REG_PREV_SP, + .fp_offset = -16, + .ra_reg = ORC_REG_PREV_SP, + .ra_offset = -8, + .type = ORC_TYPE_CALL +}; + +/* + * If we crash with IP==0, the last successfully executed instruction + * was probably an indirect function call with a NULL function pointer, + * and we don't have unwind information for NULL. + * This hardcoded ORC entry for IP==0 allows us to unwind from a NULL function + * pointer into its parent and then continue normally from there. + */ +static struct orc_entry orc_null_entry = { + .sp_reg = ORC_REG_SP, + .sp_offset = sizeof(long), + .fp_reg = ORC_REG_UNDEFINED, + .type = ORC_TYPE_CALL +}; + +static inline unsigned long orc_ip(const int *ip) +{ + return (unsigned long)ip + *ip; +} + +static struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table, + unsigned int num_entries, unsigned long ip) +{ + int *first = ip_table; + int *mid = first, *found = first; + int *last = ip_table + num_entries - 1; + + if (!num_entries) + return NULL; + + /* + * Do a binary range search to find the rightmost duplicate of a given + * starting address. Some entries are section terminators which are + * "weak" entries for ensuring there are no gaps. They should be + * ignored when they conflict with a real entry. + */ + while (first <= last) { + mid = first + ((last - first) / 2); + + if (orc_ip(mid) <= ip) { + found = mid; + first = mid + 1; + } else + last = mid - 1; + } + + return u_table + (found - ip_table); +} + +#ifdef CONFIG_MODULES +static struct orc_entry *orc_module_find(unsigned long ip) +{ + struct module *mod; + + mod = __module_address(ip); + if (!mod || !mod->arch.orc_unwind || !mod->arch.orc_unwind_ip) + return NULL; + + return __orc_find(mod->arch.orc_unwind_ip, mod->arch.orc_unwind, mod->arch.num_orcs, ip); +} +#else +static struct orc_entry *orc_module_find(unsigned long ip) +{ + return NULL; +} +#endif + +#ifdef CONFIG_DYNAMIC_FTRACE +static struct orc_entry *orc_find(unsigned long ip); + +/* + * Ftrace dynamic trampolines do not have orc entries of their own. + * But they are copies of the ftrace entries that are static and + * defined in ftrace_*.S, which do have orc entries. + * + * If the unwinder comes across a ftrace trampoline, then find the + * ftrace function that was used to create it, and use that ftrace + * function's orc entry, as the placement of the return code in + * the stack will be identical. + */ +static struct orc_entry *orc_ftrace_find(unsigned long ip) +{ + struct ftrace_ops *ops; + unsigned long tramp_addr, offset; + + ops = ftrace_ops_trampoline(ip); + if (!ops) + return NULL; + + /* Set tramp_addr to the start of the code copied by the trampoline */ + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) + tramp_addr = (unsigned long)ftrace_regs_caller; + else + tramp_addr = (unsigned long)ftrace_caller; + + /* Now place tramp_addr to the location within the trampoline ip is at */ + offset = ip - ops->trampoline; + tramp_addr += offset; + + /* Prevent unlikely recursion */ + if (ip == tramp_addr) + return NULL; + + return orc_find(tramp_addr); +} +#else +static struct orc_entry *orc_ftrace_find(unsigned long ip) +{ + return NULL; +} +#endif + +static struct orc_entry *orc_find(unsigned long ip) +{ + static struct orc_entry *orc; + + if (ip == 0) + return &orc_null_entry; + + /* For non-init vmlinux addresses, use the fast lookup table: */ + if (ip >= LOOKUP_START_IP && ip < LOOKUP_STOP_IP) { + unsigned int idx, start, stop; + + idx = (ip - LOOKUP_START_IP) / LOOKUP_BLOCK_SIZE; + + if (unlikely((idx >= lookup_num_blocks-1))) { + orc_warn("WARNING: bad lookup idx: idx=%u num=%u ip=%pB\n", + idx, lookup_num_blocks, (void *)ip); + return NULL; + } + + start = orc_lookup[idx]; + stop = orc_lookup[idx + 1] + 1; + + if (unlikely((__start_orc_unwind + start >= __stop_orc_unwind) || + (__start_orc_unwind + stop > __stop_orc_unwind))) { + orc_warn("WARNING: bad lookup value: idx=%u num=%u start=%u stop=%u ip=%pB\n", + idx, lookup_num_blocks, start, stop, (void *)ip); + return NULL; + } + + return __orc_find(__start_orc_unwind_ip + start, + __start_orc_unwind + start, stop - start, ip); + } + + /* vmlinux .init slow lookup: */ + if (is_kernel_inittext(ip)) + return __orc_find(__start_orc_unwind_ip, __start_orc_unwind, + __stop_orc_unwind_ip - __start_orc_unwind_ip, ip); + + /* Module lookup: */ + orc = orc_module_find(ip); + if (orc) + return orc; + + return orc_ftrace_find(ip); +} + +#ifdef CONFIG_MODULES + +static DEFINE_MUTEX(sort_mutex); +static int *cur_orc_ip_table = __start_orc_unwind_ip; +static struct orc_entry *cur_orc_table = __start_orc_unwind; + +static void orc_sort_swap(void *_a, void *_b, int size) +{ + int delta = _b - _a; + int *a = _a, *b = _b, tmp; + struct orc_entry *orc_a, *orc_b; + + /* Swap the .orc_unwind_ip entries: */ + tmp = *a; + *a = *b + delta; + *b = tmp - delta; + + /* Swap the corresponding .orc_unwind entries: */ + orc_a = cur_orc_table + (a - cur_orc_ip_table); + orc_b = cur_orc_table + (b - cur_orc_ip_table); + swap(*orc_a, *orc_b); +} + +static int orc_sort_cmp(const void *_a, const void *_b) +{ + const int *a = _a, *b = _b; + unsigned long a_val = orc_ip(a); + unsigned long b_val = orc_ip(b); + struct orc_entry *orc_a; + + if (a_val > b_val) + return 1; + if (a_val < b_val) + return -1; + + /* + * The "weak" section terminator entries need to always be first + * to ensure the lookup code skips them in favor of real entries. + * These terminator entries exist to handle any gaps created by + * whitelisted .o files which didn't get objtool generation. + */ + orc_a = cur_orc_table + (a - cur_orc_ip_table); + + return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1; +} + +void unwind_module_init(struct module *mod, void *_orc_ip, size_t orc_ip_size, + void *_orc, size_t orc_size) +{ + int *orc_ip = _orc_ip; + struct orc_entry *orc = _orc; + unsigned int num_entries = orc_ip_size / sizeof(int); + + WARN_ON_ONCE(orc_ip_size % sizeof(int) != 0 || + orc_size % sizeof(*orc) != 0 || + num_entries != orc_size / sizeof(*orc)); + + /* + * The 'cur_orc_*' globals allow the orc_sort_swap() callback to + * associate an .orc_unwind_ip table entry with its corresponding + * .orc_unwind entry so they can both be swapped. + */ + mutex_lock(&sort_mutex); + cur_orc_ip_table = orc_ip; + cur_orc_table = orc; + sort(orc_ip, num_entries, sizeof(int), orc_sort_cmp, orc_sort_swap); + mutex_unlock(&sort_mutex); + + mod->arch.orc_unwind_ip = orc_ip; + mod->arch.orc_unwind = orc; + mod->arch.num_orcs = num_entries; +} +#endif + +void __init unwind_init(void) +{ + int i; + size_t orc_size = (void *)__stop_orc_unwind - (void *)__start_orc_unwind; + size_t orc_ip_size = (void *)__stop_orc_unwind_ip - (void *)__start_orc_unwind_ip; + size_t num_entries = orc_ip_size / sizeof(int); + struct orc_entry *orc; + + if (!num_entries || orc_ip_size % sizeof(int) != 0 || + orc_size % sizeof(struct orc_entry) != 0 || + num_entries != orc_size / sizeof(struct orc_entry)) { + orc_warn("WARNING: Bad or missing .orc_unwind table. Disabling unwinder.\n"); + return; + } + + /* + * Note, the orc_unwind and orc_unwind_ip tables were already + * sorted at build time via the 'sorttable' tool. + * It's ready for binary search straight away, no need to sort it. + */ + + /* Initialize the fast lookup table: */ + lookup_num_blocks = orc_lookup_end - orc_lookup; + for (i = 0; i < lookup_num_blocks-1; i++) { + orc = __orc_find(__start_orc_unwind_ip, __start_orc_unwind, + num_entries, LOOKUP_START_IP + (LOOKUP_BLOCK_SIZE * i)); + if (!orc) { + orc_warn("WARNING: Corrupt .orc_unwind table. Disabling unwinder.\n"); + return; + } + + orc_lookup[i] = orc - __start_orc_unwind; + } + + /* Initialize the ending block: */ + orc = __orc_find(__start_orc_unwind_ip, __start_orc_unwind, num_entries, LOOKUP_STOP_IP); + if (!orc) { + orc_warn("WARNING: Corrupt .orc_unwind table. Disabling unwinder.\n"); + return; + } + orc_lookup[lookup_num_blocks-1] = orc - __start_orc_unwind; + + orc_init = true; +} + +static inline bool on_stack(struct stack_info *info, unsigned long addr, size_t len) +{ + unsigned long begin = info->begin; + unsigned long end = info->end; + + return (info->type != STACK_TYPE_UNKNOWN && + addr >= begin && addr < end && addr + len > begin && addr + len <= end); +} + +static bool stack_access_ok(struct unwind_state *state, unsigned long addr, size_t len) +{ + struct stack_info *info = &state->stack_info; + + if (on_stack(info, addr, len)) + return true; + + return !get_stack_info(addr, state->task, info) && on_stack(info, addr, len); +} + +unsigned long unwind_get_return_address(struct unwind_state *state) +{ + return __unwind_get_return_address(state); +} +EXPORT_SYMBOL_GPL(unwind_get_return_address); + +void unwind_start(struct unwind_state *state, struct task_struct *task, + struct pt_regs *regs) +{ + __unwind_start(state, task, regs); + state->type = UNWINDER_ORC; + if (!unwind_done(state) && !__kernel_text_address(state->pc)) + unwind_next_frame(state); +} +EXPORT_SYMBOL_GPL(unwind_start); + +static bool is_entry_func(unsigned long addr) +{ + extern u32 kernel_entry; + extern u32 kernel_entry_end; + + return addr >= (unsigned long)&kernel_entry && addr < (unsigned long)&kernel_entry_end; +} + +static inline unsigned long bt_address(unsigned long ra) +{ + extern unsigned long eentry; + + if (__kernel_text_address(ra)) + return ra; + + if (__module_text_address(ra)) + return ra; + + if (ra >= eentry && ra < eentry + EXCCODE_INT_END * VECSIZE) { + unsigned long func; + unsigned long type = (ra - eentry) / VECSIZE; + unsigned long offset = (ra - eentry) % VECSIZE; + + switch (type) { + case 0 ... EXCCODE_INT_START - 1: + func = (unsigned long)exception_table[type]; + break; + case EXCCODE_INT_START ... EXCCODE_INT_END: + func = (unsigned long)handle_vint; + break; + default: + func = (unsigned long)handle_reserved; + break; + } + + return func + offset; + } + + return ra; +} + +bool unwind_next_frame(struct unwind_state *state) +{ + unsigned long *p, pc; + struct pt_regs *regs; + struct orc_entry *orc; + struct stack_info *info = &state->stack_info; + + if (unwind_done(state)) + return false; + + /* Don't let modules unload while we're reading their ORC data. */ + preempt_disable(); + + if (is_entry_func(state->pc)) + goto end; + + orc = orc_find(state->pc); + if (!orc) { + /* + * As a fallback, try to assume this code uses a frame pointer. + * This is useful for generated code, like BPF, which ORC + * doesn't know about. This is just a guess, so the rest of + * the unwind is no longer considered reliable. + */ + orc = &orc_fp_entry; + state->error = true; + } else { + if (orc->type == ORC_TYPE_UNDEFINED) + goto err; + + if (orc->type == ORC_TYPE_END_OF_STACK) + goto end; + } + + switch (orc->sp_reg) { + case ORC_REG_SP: + if (info->type == STACK_TYPE_IRQ && state->sp == info->end) + orc->type = ORC_TYPE_REGS; + else + state->sp = state->sp + orc->sp_offset; + break; + case ORC_REG_FP: + state->sp = state->fp; + break; + default: + orc_warn("unknown SP base reg %d at %pB\n", orc->sp_reg, (void *)state->pc); + goto err; + } + + switch (orc->fp_reg) { + case ORC_REG_PREV_SP: + p = (unsigned long *)(state->sp + orc->fp_offset); + if (!stack_access_ok(state, (unsigned long)p, sizeof(unsigned long))) + goto err; + + state->fp = *p; + break; + case ORC_REG_UNDEFINED: + /* Nothing. */ + break; + default: + orc_warn("unknown FP base reg %d at %pB\n", orc->fp_reg, (void *)state->pc); + goto err; + } + + switch (orc->type) { + case ORC_TYPE_CALL: + if (orc->ra_reg == ORC_REG_PREV_SP) { + p = (unsigned long *)(state->sp + orc->ra_offset); + if (!stack_access_ok(state, (unsigned long)p, sizeof(unsigned long))) + goto err; + + pc = unwind_graph_addr(state, *p, state->sp); + pc -= LOONGARCH_INSN_SIZE; + } else if (orc->ra_reg == ORC_REG_UNDEFINED) { + if (!state->ra || state->ra == state->pc) + goto err; + + pc = unwind_graph_addr(state, state->ra, state->sp); + pc -= LOONGARCH_INSN_SIZE; + state->ra = 0; + } else { + orc_warn("unknown ra base reg %d at %pB\n", orc->ra_reg, (void *)state->pc); + goto err; + } + break; + case ORC_TYPE_REGS: + if (info->type == STACK_TYPE_IRQ && state->sp == info->end) + regs = (struct pt_regs *)info->next_sp; + else + regs = (struct pt_regs *)state->sp; + + if (!stack_access_ok(state, (unsigned long)regs, sizeof(*regs))) + goto err; + + if ((info->end == (unsigned long)regs + sizeof(*regs)) && + !regs->regs[3] && !regs->regs[1]) + goto end; + + if (user_mode(regs)) + goto end; + + pc = regs->csr_era; + if (!__kernel_text_address(pc)) + goto err; + + state->sp = regs->regs[3]; + state->ra = regs->regs[1]; + state->fp = regs->regs[22]; + get_stack_info(state->sp, state->task, info); + + break; + default: + orc_warn("unknown .orc_unwind entry type %d at %pB\n", orc->type, (void *)state->pc); + goto err; + } + + state->pc = bt_address(pc); + if (!state->pc) { + pr_err("cannot find unwind pc at %pK\n", (void *)pc); + goto err; + } + + if (!__kernel_text_address(state->pc)) + goto err; + + preempt_enable(); + return true; + +err: + state->error = true; + +end: + preempt_enable(); + state->stack_info.type = STACK_TYPE_UNKNOWN; + return false; +} +EXPORT_SYMBOL_GPL(unwind_next_frame); diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S index a5d0cd2035da04..e8e97dbf9ca40f 100644 --- a/arch/loongarch/kernel/vmlinux.lds.S +++ b/arch/loongarch/kernel/vmlinux.lds.S @@ -2,6 +2,7 @@ #include <linux/sizes.h> #include <asm/asm-offsets.h> #include <asm/thread_info.h> +#include <asm/orc_lookup.h> #define PAGE_SIZE _PAGE_SIZE #define RO_EXCEPTION_TABLE_ALIGN 4 @@ -122,6 +123,8 @@ SECTIONS } #endif + ORC_UNWIND_TABLE + .sdata : { *(.sdata) } |