From nobody Mon Sep 15 07:37:28 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2ABA0C46467 for ; Sat, 14 Jan 2023 09:28:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229995AbjANJ2P (ORCPT ); Sat, 14 Jan 2023 04:28:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229732AbjANJ1j (ORCPT ); Sat, 14 Jan 2023 04:27:39 -0500 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 9D6237A8A for ; Sat, 14 Jan 2023 01:27:36 -0800 (PST) Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8BxKuqGdcJjbZ0BAA--.4995S3; Sat, 14 Jan 2023 17:27:34 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by localhost.localdomain (Coremail) with SMTP id AQAAf8Bxb+SBdcJjcVYZAA--.11667S5; Sat, 14 Jan 2023 17:27:34 +0800 (CST) From: Tiezhu Yang To: Huacai Chen , WANG Xuerui , Masami Hiramatsu Cc: loongarch@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v11 3/6] LoongArch: Add kretprobe support Date: Sat, 14 Jan 2023 17:27:21 +0800 Message-Id: <1673688444-24251-4-git-send-email-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1673688444-24251-1-git-send-email-yangtiezhu@loongson.cn> References: <1673688444-24251-1-git-send-email-yangtiezhu@loongson.cn> X-CM-TRANSID: AQAAf8Bxb+SBdcJjcVYZAA--.11667S5 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBjvJXoWxGFWrZw45JFW3Kw48WF1kuFg_yoWrKry8pF 9rArn8Zr4I9rnavr93trWF9Fyjqr1kua12gFy7JrWrWF48WryUXr1xGr9rZF43Kws8Jr1S qr1rGrW5tFW3J37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUj1kv1TuYvTs0mT0YCTnIWj qI5I8CrVACY4xI64kE6c02F40Ex7xfYxn0WfASr-VFAUDa7-sFnT9fnUUIcSsGvfJTRUUU b28YFVCjjxCrM7AC8VAFwI0_Jr0_Gr1l1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s 1l1IIY67AEw4v_Jrv_JF1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xv wVC0I7IYx2IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwA2z4 x0Y4vEx4A2jsIE14v26r4UJVWxJr1l84ACjcxK6I8E87Iv6xkF7I0E14v26r4UJVWxJr1l e2I262IYc4CY6c8Ij28IcVAaY2xG8wAqjxCEc2xF0cIa020Ex4CE44I27wAqx4xG64xvF2 IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jw0_WrylYx0Ex4A2jsIE14v26r4j6F4U McvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwCF04k20xvY0x0EwIxGrwCFx2 IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v2 6r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67 AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IY s7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr 0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07josjUUUUUU= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Use the generic kretprobe trampoline handler to add kretprobe support for LoongArch. Signed-off-by: Tiezhu Yang --- arch/loongarch/Kconfig | 1 + arch/loongarch/kernel/Makefile | 2 +- arch/loongarch/kernel/kprobes.c | 27 +++++++++ arch/loongarch/kernel/kprobes_trampoline.S | 96 ++++++++++++++++++++++++++= ++++ 4 files changed, 125 insertions(+), 1 deletion(-) create mode 100644 arch/loongarch/kernel/kprobes_trampoline.S diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index ce930f2..134a2f8 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -104,6 +104,7 @@ config LOONGARCH select HAVE_IRQ_EXIT_ON_IRQ_STACK select HAVE_IRQ_TIME_ACCOUNTING select HAVE_KPROBES + select HAVE_KRETPROBES select HAVE_MOD_ARCH_SPECIFIC select HAVE_NMI select HAVE_PCI diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index 6fe4a4e..7ca6519 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -47,6 +47,6 @@ obj-$(CONFIG_UNWINDER_PROLOGUE) +=3D unwind_prologue.o =20 obj-$(CONFIG_PERF_EVENTS) +=3D perf_event.o perf_regs.o =20 -obj-$(CONFIG_KPROBES) +=3D kprobes.o +obj-$(CONFIG_KPROBES) +=3D kprobes.o kprobes_trampoline.o =20 CPPFLAGS_vmlinux.lds :=3D $(KBUILD_CFLAGS) diff --git a/arch/loongarch/kernel/kprobes.c b/arch/loongarch/kernel/kprobe= s.c index a0c2f9d..ced9c4c 100644 --- a/arch/loongarch/kernel/kprobes.c +++ b/arch/loongarch/kernel/kprobes.c @@ -372,6 +372,33 @@ int __init arch_populate_kprobe_blacklist(void) (unsigned long)__irqentry_text_end); } =20 +/* Called from __kretprobe_trampoline */ +void __used *trampoline_probe_handler(struct pt_regs *regs) +{ + return (void *)kretprobe_trampoline_handler(regs, NULL); +} +NOKPROBE_SYMBOL(trampoline_probe_handler); + +/* assembler function that handles the kretprobes must not be probed itsel= f */ +NOKPROBE_SYMBOL(__kretprobe_trampoline); + +void arch_prepare_kretprobe(struct kretprobe_instance *ri, + struct pt_regs *regs) +{ + ri->ret_addr =3D (kprobe_opcode_t *)regs->regs[1]; + ri->fp =3D NULL; + + /* Replace the return addr with trampoline addr */ + regs->regs[1] =3D (unsigned long)&__kretprobe_trampoline; +} +NOKPROBE_SYMBOL(arch_prepare_kretprobe); + +int arch_trampoline_kprobe(struct kprobe *p) +{ + return 0; +} +NOKPROBE_SYMBOL(arch_trampoline_kprobe); + int __init arch_init_kprobes(void) { return 0; diff --git a/arch/loongarch/kernel/kprobes_trampoline.S b/arch/loongarch/ke= rnel/kprobes_trampoline.S new file mode 100644 index 0000000..af94b0d --- /dev/null +++ b/arch/loongarch/kernel/kprobes_trampoline.S @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +#include +#include + + .text + + .macro save_all_base_regs + cfi_st ra, PT_R1 + cfi_st tp, PT_R2 + cfi_st a0, PT_R4 + cfi_st a1, PT_R5 + cfi_st a2, PT_R6 + cfi_st a3, PT_R7 + cfi_st a4, PT_R8 + cfi_st a5, PT_R9 + cfi_st a6, PT_R10 + cfi_st a7, PT_R11 + cfi_st t0, PT_R12 + cfi_st t1, PT_R13 + cfi_st t2, PT_R14 + cfi_st t3, PT_R15 + cfi_st t4, PT_R16 + cfi_st t5, PT_R17 + cfi_st t6, PT_R18 + cfi_st t7, PT_R19 + cfi_st t8, PT_R20 + cfi_st u0, PT_R21 + cfi_st fp, PT_R22 + cfi_st s0, PT_R23 + cfi_st s1, PT_R24 + cfi_st s2, PT_R25 + cfi_st s3, PT_R26 + cfi_st s4, PT_R27 + cfi_st s5, PT_R28 + cfi_st s6, PT_R29 + cfi_st s7, PT_R30 + cfi_st s8, PT_R31 + csrrd t0, LOONGARCH_CSR_CRMD + andi t0, t0, 0x7 /* extract bit[1:0] PLV, bit[2] IE */ + LONG_S t0, sp, PT_CRMD + .endm + + .macro restore_all_base_regs + cfi_ld tp, PT_R2 + cfi_ld a0, PT_R4 + cfi_ld a1, PT_R5 + cfi_ld a2, PT_R6 + cfi_ld a3, PT_R7 + cfi_ld a4, PT_R8 + cfi_ld a5, PT_R9 + cfi_ld a6, PT_R10 + cfi_ld a7, PT_R11 + cfi_ld t0, PT_R12 + cfi_ld t1, PT_R13 + cfi_ld t2, PT_R14 + cfi_ld t3, PT_R15 + cfi_ld t4, PT_R16 + cfi_ld t5, PT_R17 + cfi_ld t6, PT_R18 + cfi_ld t7, PT_R19 + cfi_ld t8, PT_R20 + cfi_ld u0, PT_R21 + cfi_ld fp, PT_R22 + cfi_ld s0, PT_R23 + cfi_ld s1, PT_R24 + cfi_ld s2, PT_R25 + cfi_ld s3, PT_R26 + cfi_ld s4, PT_R27 + cfi_ld s5, PT_R28 + cfi_ld s6, PT_R29 + cfi_ld s7, PT_R30 + cfi_ld s8, PT_R31 + LONG_L t0, sp, PT_CRMD + li.d t1, 0x7 /* mask bit[1:0] PLV, bit[2] IE */ + csrxchg t0, t1, LOONGARCH_CSR_CRMD + .endm + +SYM_CODE_START(__kretprobe_trampoline) + addi.d sp, sp, -PT_SIZE + save_all_base_regs + + addi.d t0, sp, PT_SIZE + LONG_S t0, sp, PT_R3 + + move a0, sp /* pt_regs */ + + bl trampoline_probe_handler + + /* use the result as the return-address */ + move ra, a0 + + restore_all_base_regs + addi.d sp, sp, PT_SIZE + + jr ra +SYM_CODE_END(__kretprobe_trampoline) --=20 2.1.0