From 88650dde2eeaf157eddf55cdc5d47d46f691c905 Mon Sep 17 00:00:00 2001 From: Tiezhu Yang Date: Wed, 14 May 2025 22:18:10 +0800 Subject: [PATCH] LoongArch: uprobes: Remove user_{en,dis}able_single_step() commit 0b326b2371f94e798137cc1a3c5c2eef2bc69061 upstream. When executing the "perf probe" and "perf stat" test cases about some cryptographic algorithm, the output shows that "Trace/breakpoint trap". This is because it uses the software singlestep breakpoint for uprobes on LoongArch, and no need to use the hardware singlestep. So just remove the related function call to user_{en,dis}able_single_step() for uprobes on LoongArch. How to reproduce: Please make sure CONFIG_UPROBE_EVENTS is set and openssl supports sm2 algorithm, then execute the following command. cd tools/perf && make ./perf probe -x /usr/lib64/libcrypto.so BN_mod_mul_montgomery ./perf stat -e probe_libcrypto:BN_mod_mul_montgomery openssl speed sm2 Cc: stable@vger.kernel.org Fixes: 19bc6cb64092 ("LoongArch: Add uprobes support") Signed-off-by: Tiezhu Yang Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman --- arch/loongarch/kernel/uprobes.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/arch/loongarch/kernel/uprobes.c b/arch/loongarch/kernel/uprobes.c index 87abc7137b738..0ab9d8d631c41 100644 --- a/arch/loongarch/kernel/uprobes.c +++ b/arch/loongarch/kernel/uprobes.c @@ -42,7 +42,6 @@ int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) utask->autask.saved_trap_nr = current->thread.trap_nr; current->thread.trap_nr = UPROBE_TRAP_NR; instruction_pointer_set(regs, utask->xol_vaddr); - user_enable_single_step(current); return 0; } @@ -59,8 +58,6 @@ int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) else instruction_pointer_set(regs, utask->vaddr + LOONGARCH_INSN_SIZE); - user_disable_single_step(current); - return 0; } @@ -70,7 +67,6 @@ void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) current->thread.trap_nr = utask->autask.saved_trap_nr; instruction_pointer_set(regs, utask->vaddr); - user_disable_single_step(current); } bool arch_uprobe_xol_was_trapped(struct task_struct *t)