From b59f21292e1858477d4007d9645678b88ae17abf Mon Sep 17 00:00:00 2001 From: Nam Cao Date: Tue, 29 Aug 2023 20:25:00 +0200 Subject: [PATCH] riscv: kprobes: allow writing to x0 commit 8cb22bec142624d21bc85ff96b7bad10b6220e6a upstream. Instructions can write to x0, so we should simulate these instructions normally. Currently, the kernel hangs if an instruction who writes to x0 is simulated. Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Cc: stable@vger.kernel.org Signed-off-by: Nam Cao Reviewed-by: Charlie Jenkins Acked-by: Guo Ren Link: https://lore.kernel.org/r/20230829182500.61875-1-namcaov@gmail.com Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman --- arch/riscv/kernel/probes/simulate-insn.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/probes/simulate-insn.c index d3099d67816d..6c166029079c 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -24,7 +24,7 @@ static inline bool rv_insn_reg_set_val(struct pt_regs *regs, u32 index, unsigned long val) { if (index == 0) - return false; + return true; else if (index <= 31) *((unsigned long *)regs + index) = val; else