From 6e320363339b585a36bf40d74592db3db021e017 Mon Sep 17 00:00:00 2001 From: Tiezhu Yang Date: Thu, 29 Jun 2023 20:58:44 +0800 Subject: [PATCH] LoongArch: Use larch_insn_gen_break() for kprobes For now, we can use larch_insn_gen_break() to define KPROBE_BP_INSN and KPROBE_SSTEPBP_INSN. Because larch_insn_gen_break() returns instruction word, define kprobe_opcode_t as u32, then do some small changes related with type conversion, no functional change intended. Tested-by: Jeff Xie Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen --- arch/loongarch/include/asm/kprobes.h | 2 +- arch/loongarch/kernel/kprobes.c | 33 ++++++++++++---------------- 2 files changed, 15 insertions(+), 20 deletions(-) diff --git a/arch/loongarch/include/asm/kprobes.h b/arch/loongarch/include/asm/kprobes.h index 7b9fc3ed71c3..60fa753a010d 100644 --- a/arch/loongarch/include/asm/kprobes.h +++ b/arch/loongarch/include/asm/kprobes.h @@ -22,7 +22,7 @@ do { \ #define kretprobe_blacklist_size 0 -typedef union loongarch_instruction kprobe_opcode_t; +typedef u32 kprobe_opcode_t; /* Architecture specific copy of original instruction */ struct arch_specific_insn { diff --git a/arch/loongarch/kernel/kprobes.c b/arch/loongarch/kernel/kprobes.c index 4c13c4431b67..17b040bd6067 100644 --- a/arch/loongarch/kernel/kprobes.c +++ b/arch/loongarch/kernel/kprobes.c @@ -4,19 +4,8 @@ #include #include -static const union loongarch_instruction breakpoint_insn = { - .reg0i15_format = { - .opcode = break_op, - .immediate = BRK_KPROBE_BP, - } -}; - -static const union loongarch_instruction singlestep_insn = { - .reg0i15_format = { - .opcode = break_op, - .immediate = BRK_KPROBE_SSTEPBP, - } -}; +#define KPROBE_BP_INSN larch_insn_gen_break(BRK_KPROBE_BP) +#define KPROBE_SSTEPBP_INSN larch_insn_gen_break(BRK_KPROBE_SSTEPBP) DEFINE_PER_CPU(struct kprobe *, current_kprobe); DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); @@ -24,7 +13,7 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); static void arch_prepare_ss_slot(struct kprobe *p) { p->ainsn.insn[0] = *p->addr; - p->ainsn.insn[1] = singlestep_insn; + p->ainsn.insn[1] = KPROBE_SSTEPBP_INSN; p->ainsn.restore = (unsigned long)p->addr + LOONGARCH_INSN_SIZE; } NOKPROBE_SYMBOL(arch_prepare_ss_slot); @@ -37,17 +26,20 @@ NOKPROBE_SYMBOL(arch_prepare_simulate); int arch_prepare_kprobe(struct kprobe *p) { + union loongarch_instruction insn; + if ((unsigned long)p->addr & 0x3) return -EILSEQ; /* copy instruction */ p->opcode = *p->addr; + insn.word = p->opcode; /* decode instruction */ - if (insns_not_supported(p->opcode)) + if (insns_not_supported(insn)) return -EINVAL; - if (insns_need_simulation(p->opcode)) { + if (insns_need_simulation(insn)) { p->ainsn.insn = NULL; } else { p->ainsn.insn = get_insn_slot(); @@ -68,7 +60,7 @@ NOKPROBE_SYMBOL(arch_prepare_kprobe); /* Install breakpoint in text */ void arch_arm_kprobe(struct kprobe *p) { - *p->addr = breakpoint_insn; + *p->addr = KPROBE_BP_INSN; flush_insn_slot(p); } NOKPROBE_SYMBOL(arch_arm_kprobe); @@ -163,6 +155,8 @@ NOKPROBE_SYMBOL(post_kprobe_handler); static void setup_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb, int reenter) { + union loongarch_instruction insn; + if (reenter) { save_previous_kprobe(kcb); set_current_kprobe(p); @@ -178,7 +172,8 @@ static void setup_singlestep(struct kprobe *p, struct pt_regs *regs, regs->csr_era = (unsigned long)p->ainsn.insn; } else { /* simulate single steping */ - arch_simulate_insn(p->opcode, regs); + insn.word = p->opcode; + arch_simulate_insn(insn, regs); /* now go for post processing */ post_kprobe_handler(p, kcb, regs); } @@ -253,7 +248,7 @@ bool kprobe_breakpoint_handler(struct pt_regs *regs) } } - if (addr->word != breakpoint_insn.word) { + if (*addr != KPROBE_BP_INSN) { /* * The breakpoint instruction was removed right * after we hit it. Another cpu has removed