From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8F38231830; Thu, 5 Jun 2025 13:25:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749129908; cv=none; b=N0Pcx9wVF3GGOKgEZaC5XY70Fa5h6f96FMA4YnVj8yxc+YFKVqKji0BSVpi98NMwRXsV2UZHA0c0By/ql5uoWsvPJ/jFQS7Kim46JzhIzk6Iirw6EodA3DgfCSyKtBiaeX16Ilz2i1rU/UWlPRwIi2Foa8o2fXC2O4zBe+MBIkk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749129908; c=relaxed/simple; bh=NFBN3IxVZlw631BqReuWpjDyJmkx66Zqx0KD4rxN2Hw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oL/zy5xnwCz7mTdMy4AinYGg2LpMZfd4rufXskFJI7m/E/AMzCpkWEjZtVsa9nDJoAaSHu6Rm4BazEGa3JCpr/HPyQjB061YFV9nuzhYZUtlote3UJtokfxFTvbeZe97AtldUyP6PlW3VcnhVrG8Y2Aq2x3VBVcAL+oFyECDvUA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WFaUdzSJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WFaUdzSJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53826C4CEE7; Thu, 5 Jun 2025 13:25:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1749129907; bh=NFBN3IxVZlw631BqReuWpjDyJmkx66Zqx0KD4rxN2Hw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WFaUdzSJt4wc0oqE+UL4TG9RAht2ie8wgOdc9Ac/u14u1I9/5INwMgTT3BBTJhgE9 DEQZ1atye+kP8n1qsWN0UtDWOhv+wL5NH9R96yYHFHzYqFxTkE6SrnKZWkWcKG+OzO yGcmmqu74KI2zZ6oj6a9MG0o33VtAruRnG8Ww9SIkeJ+1B6kzBOWBhhcOPLK4gyb7L s7q95YRc7oz9R435LhyDFbr6lMkmoxU8zwprjZtCwBpyHjukEyxNBGv2QH+wIUBlxM rYQH/3JUPNn86CrRzYkqR50LA9eXbMYgEb/h2aS16uq1a/6nUn2lcLAYZmMOs4C/im 3wkK3Grb79KjA== From: Jiri Olsa To: Oleg Nesterov , Peter Zijlstra , Andrii Nakryiko Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, x86@kernel.org, Song Liu , Yonghong Song , John Fastabend , Hao Luo , Steven Rostedt , Masami Hiramatsu , Alan Maguire , David Laight , =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , Ingo Molnar Subject: [PATCHv3 perf/core 06/22] uprobes: Add is_register argument to uprobe_write and uprobe_write_opcode Date: Thu, 5 Jun 2025 15:23:33 +0200 Message-ID: <20250605132350.1488129-7-jolsa@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250605132350.1488129-1-jolsa@kernel.org> References: <20250605132350.1488129-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The uprobe_write has special path to restore the original page when we write original instruction back. This happens when uprobe_write detects that we want to write anything else but breakpoint instruction. Moving the detection away and passing it to uprobe_write as argument, so it's possible to write different instructions (other than just breakpoint and rest). Acked-by: Andrii Nakryiko Acked-by: Oleg Nesterov Signed-off-by: Jiri Olsa --- arch/arm/probes/uprobes/core.c | 2 +- include/linux/uprobes.h | 5 +++-- kernel/events/uprobes.c | 21 +++++++++++---------- 3 files changed, 15 insertions(+), 13 deletions(-) diff --git a/arch/arm/probes/uprobes/core.c b/arch/arm/probes/uprobes/core.c index 885e0c5e8c20..3d96fb41d624 100644 --- a/arch/arm/probes/uprobes/core.c +++ b/arch/arm/probes/uprobes/core.c @@ -30,7 +30,7 @@ int set_swbp(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr) { return uprobe_write_opcode(auprobe, vma, vaddr, - __opcode_to_mem_arm(auprobe->bpinsn)); + __opcode_to_mem_arm(auprobe->bpinsn), true); } bool arch_uprobe_ignore(struct arch_uprobe *auprobe, struct pt_regs *regs) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 147c4a0a1af9..518b26756469 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -197,9 +197,10 @@ extern bool is_swbp_insn(uprobe_opcode_t *insn); extern bool is_trap_insn(uprobe_opcode_t *insn); extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs); extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs); -extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr, uprobe_opcode_t); +extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr, uprobe_opcode_t, + bool is_register); extern int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, const unsigned long opcode_vaddr, - uprobe_opcode_t *insn, int nbytes, uprobe_write_verify_t verify); + uprobe_opcode_t *insn, int nbytes, uprobe_write_verify_t verify, bool is_register); extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc); extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool); extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc); diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index f7feb7417a2c..1e5dc3b30707 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -402,10 +402,10 @@ static bool orig_page_is_identical(struct vm_area_struct *vma, static int __uprobe_write(struct vm_area_struct *vma, struct folio_walk *fw, struct folio *folio, - unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes) + unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes, + bool is_register) { const unsigned long vaddr = insn_vaddr & PAGE_MASK; - const bool is_register = !!is_swbp_insn(insn); bool pmd_mappable; /* For now, we'll only handle PTE-mapped folios. */ @@ -488,26 +488,27 @@ static int __uprobe_write(struct vm_area_struct *vma, * Return 0 (success) or a negative errno. */ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, - const unsigned long opcode_vaddr, uprobe_opcode_t opcode) + const unsigned long opcode_vaddr, uprobe_opcode_t opcode, + bool is_register) { - return uprobe_write(auprobe, vma, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE, verify_opcode); + return uprobe_write(auprobe, vma, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE, + verify_opcode, is_register); } int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, const unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes, - uprobe_write_verify_t verify) + uprobe_write_verify_t verify, bool is_register) { const unsigned long vaddr = insn_vaddr & PAGE_MASK; struct mm_struct *mm = vma->vm_mm; struct uprobe *uprobe; - int ret, is_register, ref_ctr_updated = 0; + int ret, ref_ctr_updated = 0; unsigned int gup_flags = FOLL_FORCE; struct mmu_notifier_range range; struct folio_walk fw; struct folio *folio; struct page *page; - is_register = is_swbp_insn(insn); uprobe = container_of(auprobe, struct uprobe, arch); if (WARN_ON_ONCE(!is_cow_mapping(vma->vm_flags))) @@ -569,7 +570,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, /* Walk the page tables again, to perform the actual update. */ if (folio_walk_start(&fw, vma, vaddr, 0)) { if (fw.page == page) - ret = __uprobe_write(vma, &fw, folio, insn_vaddr, insn, nbytes); + ret = __uprobe_write(vma, &fw, folio, insn_vaddr, insn, nbytes, is_register); folio_walk_end(&fw, vma); } @@ -611,7 +612,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, int __weak set_swbp(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr) { - return uprobe_write_opcode(auprobe, vma, vaddr, UPROBE_SWBP_INSN); + return uprobe_write_opcode(auprobe, vma, vaddr, UPROBE_SWBP_INSN, true); } /** @@ -627,7 +628,7 @@ int __weak set_orig_insn(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr) { return uprobe_write_opcode(auprobe, vma, vaddr, - *(uprobe_opcode_t *)&auprobe->insn); + *(uprobe_opcode_t *)&auprobe->insn, false); } /* uprobe should have guaranteed positive refcount */ -- 2.49.0