From nobody Mon Feb 9 04:30:19 2026 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 42BC2C00528 for ; Sun, 30 Jul 2023 08:27:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229777AbjG3I1Z (ORCPT ); Sun, 30 Jul 2023 04:27:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229753AbjG3I1X (ORCPT ); Sun, 30 Jul 2023 04:27:23 -0400 Received: from mail-lf1-x136.google.com (mail-lf1-x136.google.com [IPv6:2a00:1450:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DDCEE1709 for ; Sun, 30 Jul 2023 01:27:21 -0700 (PDT) Received: by mail-lf1-x136.google.com with SMTP id 2adb3069b0e04-4fe27849e6aso1527578e87.1 for ; Sun, 30 Jul 2023 01:27:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1690705640; x=1691310440; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+8yniXpHYJ5LlYOtJMJGlRfIyf396b9o9LmHCkYj9G0=; b=o/cTI5Ls2O0mo6N0cv3Y1lzwya7GUKhEWOZEp+1uxyeF8BIcFpDi/fx+VjyDUt4Zve kV+wrlPFqq8rHMLHlvef7fFM+cXx8pwdzBUAM4MGQrrkkGigegHRH35j6YE80rcJHlim xBaXZ2e7QjTw6Fzv+FE1ZnnNIvwlBMzs+WXUXkXwnTrVLeqXl/qnOmK1Lcbzz18QqMNx ebcfHt1kGRmfKUNWyUAFwNhnRXoPWrpXF3QdHk2V1Mqui7StMMqi/9WR82vrO6UwTVkK /iLx4pzINlfnok2v7OmHnYI8AGQ2mdIvB/meMwFELznrCsV1P7kCWp8Tfj5r0p8/Qrpi hApw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690705640; x=1691310440; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+8yniXpHYJ5LlYOtJMJGlRfIyf396b9o9LmHCkYj9G0=; b=BJbFi2eVvBEUlPPj64WfNfPchjJvgq/K9qll0ZqTHvaGf2yT+shvH/XzO4FBwqpUZl H3dpVUnJ5ywm6cM7As8Qk06qiYX3BS5yThGphLooodZrqwopsZZr+54G15DNLKGgUI1s 4kXqmoi/HgDsHFx8BJ6E99fqyPH6tSyog2VVG9hSS/wlRk1/Nx2iX5+jnO7rjXCJbL2P xvs1mB5RNBQI0n5fFeoeoFSKBusWFfd5VgpTMxgGg+/v/o+s7Hk03T6pln9u8V194bT2 cuGLCN/t9RTgD47i9Rk8t/nC6z1FR41HvdUPDPFhiW00zOVClReWTnmL9wFRMWiwuvfm XrjA== X-Gm-Message-State: ABy/qLbHdlW3AllS14udT/lZtIJbSvPCsiAImB6/WOf4QF3KZmAZ5nxg ThURRFjmjYepgKz64tPPL8w= X-Google-Smtp-Source: APBJJlFJTRX8mqrdX3Kt0N/6M1IBQQS0CKigxwiOWmQstL7Qprhb06BM4NCCMnmQNETsf9+3s7AgBg== X-Received: by 2002:a05:6512:3686:b0:4fe:18be:ef47 with SMTP id d6-20020a056512368600b004fe18beef47mr3919927lfs.67.1690705639941; Sun, 30 Jul 2023 01:27:19 -0700 (PDT) Received: from nam-dell (ip-217-105-46-58.ip.prioritytelecom.net. [217.105.46.58]) by smtp.gmail.com with ESMTPSA id k16-20020aa7d8d0000000b0051e2670d599sm3861915eds.4.2023.07.30.01.27.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Jul 2023 01:27:19 -0700 (PDT) From: Nam Cao To: Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Nam Cao Subject: [PATCH 1/3] riscv: kprobes: simulate c.j instruction Date: Sun, 30 Jul 2023 10:27:07 +0200 Message-Id: <6ef76cd9984b8015826649d13f870f8ac45a2d0d.1690704360.git.namcaov@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" kprobes currently rejects c.j instruction. Implement it. Signed-off-by: Nam Cao Reviewed-by: Charlie Jenkins --- arch/riscv/kernel/probes/decode-insn.c | 3 ++- arch/riscv/kernel/probes/simulate-insn.c | 24 ++++++++++++++++++++++++ arch/riscv/kernel/probes/simulate-insn.h | 1 + 3 files changed, 27 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/probes/decode-insn.c b/arch/riscv/kernel/pro= bes/decode-insn.c index 64f6183b4717..39adb07a342d 100644 --- a/arch/riscv/kernel/probes/decode-insn.c +++ b/arch/riscv/kernel/probes/decode-insn.c @@ -29,13 +29,14 @@ riscv_probe_decode_insn(probe_opcode_t *addr, struct ar= ch_probe_insn *api) * TODO: the REJECTED ones below need to be implemented */ #ifdef CONFIG_RISCV_ISA_C - RISCV_INSN_REJECTED(c_j, insn); RISCV_INSN_REJECTED(c_jr, insn); RISCV_INSN_REJECTED(c_jal, insn); RISCV_INSN_REJECTED(c_jalr, insn); RISCV_INSN_REJECTED(c_beqz, insn); RISCV_INSN_REJECTED(c_bnez, insn); RISCV_INSN_REJECTED(c_ebreak, insn); + + RISCV_INSN_SET_SIMULATE(c_j, insn); #endif =20 RISCV_INSN_SET_SIMULATE(jal, insn); diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/p= robes/simulate-insn.c index 7441ac8a6843..3ba45c612cd8 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -188,3 +188,27 @@ bool __kprobes simulate_branch(u32 opcode, unsigned lo= ng addr, struct pt_regs *r =20 return true; } + +bool __kprobes simulate_c_j(u32 opcode, unsigned long addr, struct pt_regs= *regs) +{ + /* + * 15 13 12 2 1 0 + * | funct3 | offset[11|4|9:8|10|6|7|3:1|5] | opcode | + * 3 11 2 + */ + + s32 offset; + + offset =3D ((opcode >> 3) & 0x7) << 1; + offset |=3D ((opcode >> 11) & 0x1) << 4; + offset |=3D ((opcode >> 2) & 0x1) << 5; + offset |=3D ((opcode >> 7) & 0x1) << 6; + offset |=3D ((opcode >> 6) & 0x1) << 7; + offset |=3D ((opcode >> 9) & 0x3) << 8; + offset |=3D ((opcode >> 8) & 0x1) << 10; + offset |=3D ((opcode >> 12) & 0x1) << 11; + + instruction_pointer_set(regs, addr + sign_extend32(offset, 11)); + + return true; +} diff --git a/arch/riscv/kernel/probes/simulate-insn.h b/arch/riscv/kernel/p= robes/simulate-insn.h index 61e35db31001..4bd6c266e7d3 100644 --- a/arch/riscv/kernel/probes/simulate-insn.h +++ b/arch/riscv/kernel/probes/simulate-insn.h @@ -24,5 +24,6 @@ bool simulate_auipc(u32 opcode, unsigned long addr, struc= t pt_regs *regs); bool simulate_branch(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_jal(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs); +bool simulate_c_j(u32 opcode, unsigned long addr, struct pt_regs *regs); =20 #endif /* _RISCV_KERNEL_PROBES_SIMULATE_INSN_H */ --=20 2.34.1 From nobody Mon Feb 9 04:30:19 2026 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 57F1DC41513 for ; Sun, 30 Jul 2023 08:27:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229673AbjG3I12 (ORCPT ); Sun, 30 Jul 2023 04:27:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37528 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229776AbjG3I1Z (ORCPT ); Sun, 30 Jul 2023 04:27:25 -0400 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A208010FF for ; 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[217.105.46.58]) by smtp.gmail.com with ESMTPSA id qk29-20020a170906d9dd00b0098e34446464sm4327706ejb.25.2023.07.30.01.27.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Jul 2023 01:27:21 -0700 (PDT) From: Nam Cao To: Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Nam Cao Subject: [PATCH 2/3] riscv: kprobes: simulate c.jr and c.jalr instructions Date: Sun, 30 Jul 2023 10:27:08 +0200 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" kprobes currently rejects c.jr and c.jalr instructions. Implement them. Signed-off-by: Nam Cao Reviewed-by: Charlie Jenkins --- arch/riscv/kernel/probes/decode-insn.c | 4 +-- arch/riscv/kernel/probes/simulate-insn.c | 37 ++++++++++++++++++++++++ arch/riscv/kernel/probes/simulate-insn.h | 2 ++ 3 files changed, 41 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/probes/decode-insn.c b/arch/riscv/kernel/pro= bes/decode-insn.c index 39adb07a342d..6dba23a55ac7 100644 --- a/arch/riscv/kernel/probes/decode-insn.c +++ b/arch/riscv/kernel/probes/decode-insn.c @@ -29,14 +29,14 @@ riscv_probe_decode_insn(probe_opcode_t *addr, struct ar= ch_probe_insn *api) * TODO: the REJECTED ones below need to be implemented */ #ifdef CONFIG_RISCV_ISA_C - RISCV_INSN_REJECTED(c_jr, insn); RISCV_INSN_REJECTED(c_jal, insn); - RISCV_INSN_REJECTED(c_jalr, insn); RISCV_INSN_REJECTED(c_beqz, insn); RISCV_INSN_REJECTED(c_bnez, insn); RISCV_INSN_REJECTED(c_ebreak, insn); =20 RISCV_INSN_SET_SIMULATE(c_j, insn); + RISCV_INSN_SET_SIMULATE(c_jr, insn); + RISCV_INSN_SET_SIMULATE(c_jalr, insn); #endif =20 RISCV_INSN_SET_SIMULATE(jal, insn); diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/p= robes/simulate-insn.c index 3ba45c612cd8..1ead6f4951f9 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -212,3 +212,40 @@ bool __kprobes simulate_c_j(u32 opcode, unsigned long = addr, struct pt_regs *regs =20 return true; } + +static bool __kprobes simulate_c_jr_jalr(u32 opcode, unsigned long addr, s= truct pt_regs *regs, + bool is_jalr) +{ + /* + * 15 12 11 7 6 2 1 0 + * | funct4 | rs1 | rs2 | op | + * 4 5 5 2 + */ + + unsigned long jump_addr; + + u32 rs1 =3D (opcode >> 7) & 0x1f; + + if (rs1 =3D=3D 0) /* C.JR is only valid when rs1 !=3D x0 */ + return false; + + if (!rv_insn_reg_get_val(regs, rs1, &jump_addr)) + return false; + + if (is_jalr && !rv_insn_reg_set_val(regs, 1, addr + 2)) + return false; + + instruction_pointer_set(regs, jump_addr); + + return true; +} + +bool __kprobes simulate_c_jr(u32 opcode, unsigned long addr, struct pt_reg= s *regs) +{ + return simulate_c_jr_jalr(opcode, addr, regs, false); +} + +bool __kprobes simulate_c_jalr(u32 opcode, unsigned long addr, struct pt_r= egs *regs) +{ + return simulate_c_jr_jalr(opcode, addr, regs, true); +} diff --git a/arch/riscv/kernel/probes/simulate-insn.h b/arch/riscv/kernel/p= robes/simulate-insn.h index 4bd6c266e7d3..472a1948ec4f 100644 --- a/arch/riscv/kernel/probes/simulate-insn.h +++ b/arch/riscv/kernel/probes/simulate-insn.h @@ -25,5 +25,7 @@ bool simulate_branch(u32 opcode, unsigned long addr, stru= ct pt_regs *regs); bool simulate_jal(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_c_j(u32 opcode, unsigned long addr, struct pt_regs *regs); +bool simulate_c_jr(u32 opcode, unsigned long addr, struct pt_regs *regs); +bool simulate_c_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs); =20 #endif /* _RISCV_KERNEL_PROBES_SIMULATE_INSN_H */ --=20 2.34.1 From nobody Mon Feb 9 04:30:19 2026 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 670E4C001DC for ; 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[217.105.46.58]) by smtp.gmail.com with ESMTPSA id n16-20020a1709067b5000b009927a49ba94sm4333519ejo.169.2023.07.30.01.27.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Jul 2023 01:27:23 -0700 (PDT) From: Nam Cao To: Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Nam Cao Subject: [PATCH 3/3] riscv: kprobes: simulate c.beqz and c.bnez Date: Sun, 30 Jul 2023 10:27:09 +0200 Message-Id: <1d879dba4e4ee9a82e27625d6483b5c9cfed684f.1690704360.git.namcaov@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" kprobes currently rejects instruction c.beqz and c.bnez. Implement them. Signed-off-by: Nam Cao Reviewed-by: Charlie Jenkins --- arch/riscv/kernel/probes/decode-insn.c | 4 +-- arch/riscv/kernel/probes/simulate-insn.c | 44 ++++++++++++++++++++++++ arch/riscv/kernel/probes/simulate-insn.h | 2 ++ 3 files changed, 48 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/probes/decode-insn.c b/arch/riscv/kernel/pro= bes/decode-insn.c index 6dba23a55ac7..65d9590bfb9f 100644 --- a/arch/riscv/kernel/probes/decode-insn.c +++ b/arch/riscv/kernel/probes/decode-insn.c @@ -30,13 +30,13 @@ riscv_probe_decode_insn(probe_opcode_t *addr, struct ar= ch_probe_insn *api) */ #ifdef CONFIG_RISCV_ISA_C RISCV_INSN_REJECTED(c_jal, insn); - RISCV_INSN_REJECTED(c_beqz, insn); - RISCV_INSN_REJECTED(c_bnez, insn); RISCV_INSN_REJECTED(c_ebreak, insn); =20 RISCV_INSN_SET_SIMULATE(c_j, insn); RISCV_INSN_SET_SIMULATE(c_jr, insn); RISCV_INSN_SET_SIMULATE(c_jalr, insn); + RISCV_INSN_SET_SIMULATE(c_beqz, insn); + RISCV_INSN_SET_SIMULATE(c_bnez, insn); #endif =20 RISCV_INSN_SET_SIMULATE(jal, insn); diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/p= robes/simulate-insn.c index 1ead6f4951f9..d3099d67816d 100644 --- a/arch/riscv/kernel/probes/simulate-insn.c +++ b/arch/riscv/kernel/probes/simulate-insn.c @@ -249,3 +249,47 @@ bool __kprobes simulate_c_jalr(u32 opcode, unsigned lo= ng addr, struct pt_regs *r { return simulate_c_jr_jalr(opcode, addr, regs, true); } + +static bool __kprobes simulate_c_bnez_beqz(u32 opcode, unsigned long addr,= struct pt_regs *regs, + bool is_bnez) +{ + /* + * 15 13 12 10 9 7 6 2 1 0 + * | funct3 | offset[8|4:3] | rs1' | offset[7:6|2:1|5] | op | + * 3 3 3 5 2 + */ + + s32 offset; + u32 rs1; + unsigned long rs1_val; + + rs1 =3D 0x8 | ((opcode >> 7) & 0x7); + + if (!rv_insn_reg_get_val(regs, rs1, &rs1_val)) + return false; + + if ((rs1_val !=3D 0 && is_bnez) || (rs1_val =3D=3D 0 && !is_bnez)) { + offset =3D ((opcode >> 3) & 0x3) << 1; + offset |=3D ((opcode >> 10) & 0x3) << 3; + offset |=3D ((opcode >> 2) & 0x1) << 5; + offset |=3D ((opcode >> 5) & 0x3) << 6; + offset |=3D ((opcode >> 12) & 0x1) << 8; + offset =3D sign_extend32(offset, 8); + } else { + offset =3D 2; + } + + instruction_pointer_set(regs, addr + offset); + + return true; +} + +bool __kprobes simulate_c_bnez(u32 opcode, unsigned long addr, struct pt_r= egs *regs) +{ + return simulate_c_bnez_beqz(opcode, addr, regs, true); +} + +bool __kprobes simulate_c_beqz(u32 opcode, unsigned long addr, struct pt_r= egs *regs) +{ + return simulate_c_bnez_beqz(opcode, addr, regs, false); +} diff --git a/arch/riscv/kernel/probes/simulate-insn.h b/arch/riscv/kernel/p= robes/simulate-insn.h index 472a1948ec4f..44ebbc444db9 100644 --- a/arch/riscv/kernel/probes/simulate-insn.h +++ b/arch/riscv/kernel/probes/simulate-insn.h @@ -27,5 +27,7 @@ bool simulate_jalr(u32 opcode, unsigned long addr, struct= pt_regs *regs); bool simulate_c_j(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_c_jr(u32 opcode, unsigned long addr, struct pt_regs *regs); bool simulate_c_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs); +bool simulate_c_bnez(u32 opcode, unsigned long addr, struct pt_regs *regs); +bool simulate_c_beqz(u32 opcode, unsigned long addr, struct pt_regs *regs); =20 #endif /* _RISCV_KERNEL_PROBES_SIMULATE_INSN_H */ --=20 2.34.1 From nobody Mon Feb 9 04:30:19 2026 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 7969BC04A94 for ; Sun, 30 Jul 2023 08:27:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229809AbjG3I1h (ORCPT ); Sun, 30 Jul 2023 04:27:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229791AbjG3I13 (ORCPT ); Sun, 30 Jul 2023 04:27:29 -0400 Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A19910FF for ; 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[217.105.46.58]) by smtp.gmail.com with ESMTPSA id m17-20020aa7d351000000b005224c6b2183sm3790791edr.39.2023.07.30.01.27.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Jul 2023 01:27:24 -0700 (PDT) From: Nam Cao To: Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Nam Cao Subject: test code for kprobe Date: Sun, 30 Jul 2023 10:27:10 +0200 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" --- drivers/test_kprobe/Makefile | 3 + drivers/test_kprobe/test_kprobe.c | 265 ++++++++++++++++++++++++++++++ 2 files changed, 268 insertions(+) create mode 100644 drivers/test_kprobe/Makefile create mode 100644 drivers/test_kprobe/test_kprobe.c diff --git a/drivers/test_kprobe/Makefile b/drivers/test_kprobe/Makefile new file mode 100644 index 000000000000..c3c39bd0f8b5 --- /dev/null +++ b/drivers/test_kprobe/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 +# +obj-m +=3D test_kprobe.o diff --git a/drivers/test_kprobe/test_kprobe.c b/drivers/test_kprobe/test_k= probe.c new file mode 100644 index 000000000000..543108c5fc8a --- /dev/null +++ b/drivers/test_kprobe/test_kprobe.c @@ -0,0 +1,265 @@ +#include +#include +#include +#include +MODULE_LICENSE("Dual BSD/GPL"); + +__attribute__ ((naked)) +int sample_c_j(void) { + __asm__( + "c.j label_cj\n" + "li a0, 0\n ret\n" + "li a0, 1\n ret\n" + "li a0, 2\n ret\n" + "li a0, 3\n ret\n" + "label_cj:\n" + "li a0, 4\n ret\n" + "li a0, 5\n ret\n" + "li a0, 6\n ret\n" + ); +} + +__attribute__ ((naked)) +int sample_c_jr(void) { + __asm__( + "la a0, label_c_jr\n" + "c_jr_location:\n" + "c.jr a0\n" + "li a0, 0\n ret\n" + "li a0, 1\n ret\n" + "li a0, 2\n ret\n" + "li a0, 3\n ret\n" + "label_c_jr:\n" + "li a0, 4\n ret\n" + "li a0, 5\n ret\n" + "li a0, 6\n ret\n" + ); +} + +__attribute__ ((naked)) +int sample_c_jalr(void) { + __asm__( + "mv a1, x1\n" + "la a0, label_c_jalr\n" + "c_jalr_location:\n" + "c.jalr a0\n" + + "addi a0, a0, -5\n" + "jr a1\n" + + "label_c_jalr:\n" + "li a0, 9\n ret\n" + ); +} + +__attribute__ ((naked)) +int sample_c_beqz(int a0) { + __asm__( + "c.beqz a0, beqz_label\n" + "li a0, 10\n ret\n" + "beqz_label:\n" + "li a0, 4\n ret\n" + ); +} + +__attribute__ ((naked)) +int sample_c_bnez(int a0) { + __asm__( + "c.bnez a0, bnez_label\n" + "li a0, 10\n ret\n" + "bnez_label:\n" + "li a0, 4\n ret\n" + ); +} + +static int pre_handler(struct kprobe *p, struct pt_regs *regs) { + printk("pre_handler() called\n"); + + return 0; +} + +static int test_c_j(void) { + static struct kprobe kp; + + int ret; + + /* Test C.J */ + kp.symbol_name =3D "sample_c_j"; + kp.pre_handler =3D pre_handler; + + ret =3D register_kprobe(&kp); + if (ret) { + printk("Couldn't register kprobe, err=3D%d\n", ret); + return -1; + } + + ret =3D sample_c_j(); + if (ret !=3D 4) { + printk("ERROR: expect value 4, got %d\n", ret); + return -1; + } + else { + printk("Got value 4, all good!\n"); + return 0; + } +} + +static int test_c_jr(void) { + static struct kprobe kp; + int ret; + + /* Test C.JR */ + kp.symbol_name =3D "c_jr_location"; + kp.pre_handler =3D pre_handler; + + ret =3D register_kprobe(&kp); + if (ret) { + printk("Couldn't register kprobe, err=3D%d\n", ret); + return -1; + } + + ret =3D sample_c_jr(); + if (ret !=3D 4) { + printk("Expect value 4, got %d\n", ret); + return -1; + } + else { + printk("Got value 4, all good!\n"); + return 0; + } +} + +static int test_c_jalr(void) { + struct kprobe kp; + int ret; + + memset(&kp, 0, sizeof(kp)); + + /* Test C.JR */ + kp.symbol_name =3D "c_jalr_location"; + kp.pre_handler =3D pre_handler; + + ret =3D register_kprobe(&kp); + if (ret) { + printk("Couldn't register kprobe, err=3D%d\n", ret); + return -1; + } + + ret =3D sample_c_jalr(); + if (ret !=3D 4) { + printk("Expect value 4, got %d\n", ret); + return -1; + } + else { + printk("Got value 4, all good!\n"); + } + + unregister_kprobe(&kp); + + return 0; +} + +static int test_c_bnez(void) { + static struct kprobe kp; + + int ret; + + /* Test C.JR */ + kp.symbol_name =3D "sample_c_bnez"; + kp.pre_handler =3D pre_handler; + + ret =3D register_kprobe(&kp); + if (ret) { + printk("Couldn't register kprobe, err=3D%d\n", ret); + return -1; + } + + ret =3D sample_c_bnez(1); + if (ret !=3D 4) { + printk("Expect value 4, got %d\n", ret); + return -1; + } else { + printk("Got value 4, all good!\n"); + } + + ret =3D sample_c_bnez(0); + if (ret !=3D 10) { + printk("Expect value 10, got %d\n", ret); + return -1; + } else { + printk("Got value 4, all good!\n"); + } + + return 0; +} + +static int test_c_beqz(void) { + static struct kprobe kp; + + int ret; + + /* Test C.JR */ + kp.symbol_name =3D "sample_c_beqz"; + kp.pre_handler =3D pre_handler; + + ret =3D register_kprobe(&kp); + if (ret) { + printk("Couldn't register kprobe, err=3D%d\n", ret); + return -1; + } + + ret =3D sample_c_beqz(0); + if (ret !=3D 4) { + printk("Expect value 4, got %d\n", ret); + return -1; + } + else { + printk("Got value 4, all good!\n"); + return 0; + } + + ret =3D sample_c_beqz(1); + if (ret !=3D 10) { + printk("Expect value 10, got %d\n", ret); + return -1; + } + else { + printk("Got value 4, all good!\n"); + return 0; + } +} + +static int hello_init(void) +{ + printk("Hello\n"); + + printk("Testing C.J...\n"); + if (test_c_j()) + return -1; + + printk("Testing C.JR...\n"); + if (test_c_jr()) + return -1; + + printk("Testing C.JALR...\n"); + if (test_c_jalr()) + return -1; + + printk("Testing C.BNEZ...\n"); + if (test_c_bnez()) + return -1; + + printk("Testing C.BEQZ...\n"); + if (test_c_beqz()) + return -1; + + return 0; +} + +static void hello_exit(void) +{ + printk("Goodbye\n"); +} + +module_init(hello_init); +module_exit(hello_exit); --=20 2.34.1