From patchwork Thu May 5 12:19:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 12839497 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 3504CC433FE for ; Thu, 5 May 2022 12:19:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376531AbiEEMWy (ORCPT ); Thu, 5 May 2022 08:22:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376505AbiEEMWy (ORCPT ); Thu, 5 May 2022 08:22:54 -0400 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3E6A354F92; Thu, 5 May 2022 05:19:14 -0700 (PDT) Received: from linux.localdomain (unknown [113.200.148.30]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9BxYNq9wHNiWN0KAA--.42405S3; Thu, 05 May 2022 20:19:09 +0800 (CST) From: Tiezhu Yang To: Thomas Bogendoerfer , Masami Hiramatsu , Steven Rostedt , Shuah Khan Cc: Xuefeng Li , linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/2] selftests/ftrace: Save kprobe_events to test log Date: Thu, 5 May 2022 20:19:07 +0800 Message-Id: <1651753148-1464-2-git-send-email-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1651753148-1464-1-git-send-email-yangtiezhu@loongson.cn> References: <1651753148-1464-1-git-send-email-yangtiezhu@loongson.cn> X-CM-TRANSID: AQAAf9BxYNq9wHNiWN0KAA--.42405S3 X-Coremail-Antispam: 1UD129KBjvJXoW7Gry7GF4rZFykAFWxZFyxKrg_yoW8JF1kpa 93W3Z8Ka18J3W7JryxCw1DGrW09r4kArWUCryrXry3Zwn5ZFsrJr1IgFWDGF93urZYgryf Aw1ayry7ZF97Ja7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBa14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r1I6r4UM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r106r15McIj6I8E87Iv67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkIecxEwVAFwVW5JwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAI cVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2js IEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUx3kZUUUUU= X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org It may lead to kernel panic when execute the following testcase on mips: # ./ftracetest test.d/kprobe/multiple_kprobes.tc A preliminary analysis shows that the issue is related with echo 1 > events/kprobes/enable after add the 256 probe points. In order to find the root cause, I want to verify which probe point has problem, so it is necessary to save kprobe_events to test log. With this patch, we can get the 256 probe points in the test log through the following command: # ./ftracetest test.d/kprobe/multiple_kprobes.tc -vvv -k Signed-off-by: Tiezhu Yang Acked-by: Masami Hiramatsu --- tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc index 312d237..be754f5 100644 --- a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc +++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc @@ -25,6 +25,8 @@ if [ $L -ne 256 ]; then exit_fail fi +cat kprobe_events >> $testlog + echo 1 > events/kprobes/enable echo 0 > events/kprobes/enable echo > kprobe_events From patchwork Thu May 5 12:19:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 12839498 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 86607C433FE for ; Thu, 5 May 2022 12:19:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376583AbiEEMW5 (ORCPT ); Thu, 5 May 2022 08:22:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56376 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376563AbiEEMW4 (ORCPT ); Thu, 5 May 2022 08:22:56 -0400 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 2D49753B48; Thu, 5 May 2022 05:19:16 -0700 (PDT) Received: from linux.localdomain (unknown [113.200.148.30]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9BxYNq9wHNiWN0KAA--.42405S4; Thu, 05 May 2022 20:19:10 +0800 (CST) From: Tiezhu Yang To: Thomas Bogendoerfer , Masami Hiramatsu , Steven Rostedt , Shuah Khan Cc: Xuefeng Li , linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] MIPS: Use NOKPROBE_SYMBOL() instead of __kprobes annotation Date: Thu, 5 May 2022 20:19:08 +0800 Message-Id: <1651753148-1464-3-git-send-email-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1651753148-1464-1-git-send-email-yangtiezhu@loongson.cn> References: <1651753148-1464-1-git-send-email-yangtiezhu@loongson.cn> X-CM-TRANSID: AQAAf9BxYNq9wHNiWN0KAA--.42405S4 X-Coremail-Antispam: 1UD129KBjvJXoWxKw1kJw4DZw4fXw48Kr13CFg_yoWfGFWrpF 98Aw15Kr4rXaykuF9rAwsYyr1Syr4kZ3yUCrWUG34Sq3WUtr15tF1IgrWjyry5Gr9Y9F43 Zr4jyryUZF97CrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBa14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jryl82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UM2 8EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r106r15McIj6I8E87Iv67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xv r2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7MxkIecxEwVAFwVW5JwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAI cVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2js IEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JU01vsUUUUU= X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org If define CONFIG_KPROBES, __kprobes annotation forces the whole function into the ".kprobes.text" section, NOKPROBE_SYMBOL() just stores the given function address in the "_kprobe_blacklist" section which is introduced to maintain kprobes blacklist. Modify the related code to use NOKPROBE_SYMBOL() to protect functions from kprobes instead of __kprobes annotation under arch/mips. Signed-off-by: Tiezhu Yang --- arch/mips/kernel/kprobes.c | 45 ++++++++++++++++++++++++++++++++------------- arch/mips/mm/fault.c | 6 ++++-- 2 files changed, 36 insertions(+), 15 deletions(-) diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c index 6c7f3b1..21f9cec 100644 --- a/arch/mips/kernel/kprobes.c +++ b/arch/mips/kernel/kprobes.c @@ -44,10 +44,11 @@ static const union mips_instruction breakpoint2_insn = { DEFINE_PER_CPU(struct kprobe *, current_kprobe); DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); -static int __kprobes insn_has_delayslot(union mips_instruction insn) +static int insn_has_delayslot(union mips_instruction insn) { return __insn_has_delay_slot(insn); } +NOKPROBE_SYMBOL(insn_has_delayslot); /* * insn_has_ll_or_sc function checks whether instruction is ll or sc @@ -56,7 +57,7 @@ static int __kprobes insn_has_delayslot(union mips_instruction insn) * instructions; cannot do much about breakpoint in the middle of * ll/sc pair; it is upto user to avoid those places */ -static int __kprobes insn_has_ll_or_sc(union mips_instruction insn) +static int insn_has_ll_or_sc(union mips_instruction insn) { int ret = 0; @@ -72,8 +73,9 @@ static int __kprobes insn_has_ll_or_sc(union mips_instruction insn) } return ret; } +NOKPROBE_SYMBOL(insn_has_ll_or_sc); -int __kprobes arch_prepare_kprobe(struct kprobe *p) +int arch_prepare_kprobe(struct kprobe *p) { union mips_instruction insn; union mips_instruction prev_insn; @@ -132,26 +134,30 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) out: return ret; } +NOKPROBE_SYMBOL(arch_prepare_kprobe); -void __kprobes arch_arm_kprobe(struct kprobe *p) +void arch_arm_kprobe(struct kprobe *p) { *p->addr = breakpoint_insn; flush_insn_slot(p); } +NOKPROBE_SYMBOL(arch_arm_kprobe); -void __kprobes arch_disarm_kprobe(struct kprobe *p) +void arch_disarm_kprobe(struct kprobe *p) { *p->addr = p->opcode; flush_insn_slot(p); } +NOKPROBE_SYMBOL(arch_disarm_kprobe); -void __kprobes arch_remove_kprobe(struct kprobe *p) +void arch_remove_kprobe(struct kprobe *p) { if (p->ainsn.insn) { free_insn_slot(p->ainsn.insn, 0); p->ainsn.insn = NULL; } } +NOKPROBE_SYMBOL(arch_remove_kprobe); static void save_previous_kprobe(struct kprobe_ctlblk *kcb) { @@ -161,6 +167,7 @@ static void save_previous_kprobe(struct kprobe_ctlblk *kcb) kcb->prev_kprobe.saved_SR = kcb->kprobe_saved_SR; kcb->prev_kprobe.saved_epc = kcb->kprobe_saved_epc; } +NOKPROBE_SYMBOL(save_previous_kprobe); static void restore_previous_kprobe(struct kprobe_ctlblk *kcb) { @@ -170,6 +177,7 @@ static void restore_previous_kprobe(struct kprobe_ctlblk *kcb) kcb->kprobe_saved_SR = kcb->prev_kprobe.saved_SR; kcb->kprobe_saved_epc = kcb->prev_kprobe.saved_epc; } +NOKPROBE_SYMBOL(restore_previous_kprobe); static void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb) @@ -178,6 +186,7 @@ static void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, kcb->kprobe_saved_SR = kcb->kprobe_old_SR = (regs->cp0_status & ST0_IE); kcb->kprobe_saved_epc = regs->cp0_epc; } +NOKPROBE_SYMBOL(set_current_kprobe); /** * evaluate_branch_instrucion - @@ -225,6 +234,7 @@ static int evaluate_branch_instruction(struct kprobe *p, struct pt_regs *regs, return -EFAULT; } +NOKPROBE_SYMBOL(evaluate_branch_instruction); static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb) @@ -244,6 +254,7 @@ static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, } regs->cp0_epc = (unsigned long)&p->ainsn.insn[0]; } +NOKPROBE_SYMBOL(prepare_singlestep); /* * Called after single-stepping. p->addr is the address of the @@ -257,7 +268,7 @@ static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs, * breakpoint trap. In case of branch instructions, the target * epc to be restored. */ -static void __kprobes resume_execution(struct kprobe *p, +static void resume_execution(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb) { @@ -268,8 +279,9 @@ static void __kprobes resume_execution(struct kprobe *p, regs->cp0_epc = orig_epc + 4; } } +NOKPROBE_SYMBOL(resume_execution); -static int __kprobes kprobe_handler(struct pt_regs *regs) +static int kprobe_handler(struct pt_regs *regs) { struct kprobe *p; int ret = 0; @@ -367,8 +379,9 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) return ret; } +NOKPROBE_SYMBOL(kprobe_handler); -static inline int post_kprobe_handler(struct pt_regs *regs) +static int post_kprobe_handler(struct pt_regs *regs) { struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); @@ -396,6 +409,7 @@ static inline int post_kprobe_handler(struct pt_regs *regs) return 1; } +NOKPROBE_SYMBOL(post_kprobe_handler); int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { @@ -411,11 +425,12 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr) } return 0; } +NOKPROBE_SYMBOL(kprobe_fault_handler); /* * Wrapper routine for handling exceptions. */ -int __kprobes kprobe_exceptions_notify(struct notifier_block *self, +int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data) { @@ -446,6 +461,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, } return ret; } +NOKPROBE_SYMBOL(kprobe_exceptions_notify); /* * Function return probe trampoline: @@ -469,7 +485,7 @@ static void __used kretprobe_trampoline_holder(void) void __kretprobe_trampoline(void); -void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, +void arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *) regs->regs[31]; @@ -478,11 +494,12 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, /* Replace the return addr with trampoline addr */ regs->regs[31] = (unsigned long)__kretprobe_trampoline; } +NOKPROBE_SYMBOL(arch_prepare_kretprobe); /* * Called when the probe at kretprobe trampoline is hit */ -static int __kprobes trampoline_probe_handler(struct kprobe *p, +static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { instruction_pointer(regs) = __kretprobe_trampoline_handler(regs, NULL); @@ -493,14 +510,16 @@ static int __kprobes trampoline_probe_handler(struct kprobe *p, */ return 1; } +NOKPROBE_SYMBOL(trampoline_probe_handler); -int __kprobes arch_trampoline_kprobe(struct kprobe *p) +int arch_trampoline_kprobe(struct kprobe *p) { if (p->addr == (kprobe_opcode_t *)__kretprobe_trampoline) return 1; return 0; } +NOKPROBE_SYMBOL(arch_trampoline_kprobe); static struct kprobe trampoline_p = { .addr = (kprobe_opcode_t *)__kretprobe_trampoline, diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c index 44f9810..b08bc55 100644 --- a/arch/mips/mm/fault.c +++ b/arch/mips/mm/fault.c @@ -35,7 +35,7 @@ int show_unhandled_signals = 1; * and the problem, and then passes it off to one of the appropriate * routines. */ -static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, +static void __do_page_fault(struct pt_regs *regs, unsigned long write, unsigned long address) { struct vm_area_struct * vma = NULL; @@ -322,8 +322,9 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write, } #endif } +NOKPROBE_SYMBOL(__do_page_fault); -asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, +asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write, unsigned long address) { enum ctx_state prev_state; @@ -332,3 +333,4 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, __do_page_fault(regs, write, address); exception_exit(prev_state); } +NOKPROBE_SYMBOL(do_page_fault);