From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.101 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793901036; b=Zmi/qiMsJE5RdKfbN889oeKxvZNsUtYPtiNhva5fYmIEgImWWDUjG72YSfcjuvFZsFAe AuSIbXy1QIQdOXoikz92hHz1RY6MKaivI/QCxSwG3rQOc/dV1TUHkfBbOGa1RLptFxItz hcuAxCLBx2nv7b47CdOuWecH1O3PnHrsD1SzXGp0H5fdagGANReTyIW+vjw7zrywaIv45 +hCmeuOfrE8/BiGePEqRWWCLNdZIkObha4ayq0GILCtK82aPVfnAOh5jjA+kCE2KrXRTT y6DaFVArxVa8yDY6D/bBv6GqE1DcuW1mpV80vicMHCE1uYMYXLJt1hhSc5GSI3Tt7LA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793901036; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:From:To:Cc:Subject:Date:Message-Id: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=/oKxyFlE8NF55gLRR8X32aZCsov7qgh8L2DMbJVvrnI=; b=IYb538mW2Vfh17W77SQqh2kDucZri6pE/sO2ycSi/u55dvkVBq8D+G69kTiXScBnCnW9 PzoQk7XAi/AIUeD3vtgdODWQQCgcbRKfsB+3ZPYQXMW4+e2FtCcN6LDpVtt6arb0ojWVb uKeTsplKbnwTfXCjoBce1xPa96Q7l5V8kvXK9iua4h93Zs72LZsjmG8/eivxJ8XjjR6Cv waty487LLXs/7UjSa/v1ffMG4D0IrLq8yqDhaVGYgy5GVIfyWowRhiR75CZD5kCylAXcO RrEPS6fQceaNHAtZ0YVFzQHje+h78rAhOuR+NqTcdnx+kiTryEQmD+2GHUOIesX2oTQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=ffTWI+3M; arc=none smtp.remote-ip=91.218.175.101 Received: from mta0.migadu.com (out-101.mta0.migadu.com [91.218.175.101]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C56D606A326 for ; Thu, 5 Nov 2026 17:50:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 1C56D606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=ffTWI+3M X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=Cp8CTnHN4cmW6VIwx8ueqqMqNedibQwmmaim2YdoyDI=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1793901034; v=1; x=1794505834; b=ffTWI+3MqU9kkAz7Il/roqCAO8FxgUSWfjeOdYDhXcA/owTZQKd7TBy9/f/Slm3pr+0PdzxD 3myBE4M2BHQkCx9OsCBAoTTLhbYtbQ4HkgG6r7kP/J3RI8WZaQAeLvk186HbUXSIG88qCVfVm59 yVYZJ1XNJJyTtYmbl1SKSIWA= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta11.migadu.com with ESMTPS id 01ec1ce46df10c25; Thu, 05 Nov 2026 17:50:34 +0000 X-Mizu-Trace-ID: 01ec1ce46df10c25 X-Migadu-Flow: FLOW_OUT From: wen.yang@linux.dev To: Gabriele Monaco Cc: Nam Cao , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, Wen Yang Subject: [PATCH v8 09/14] rv: Add generic uprobe infrastructure for RV monitors Date: Fri, 6 Nov 2026 01:49:09 +0800 Message-Id: <21469501d58c0b7efc662226f4c9e9a9d7d32847.1793900349.git.wen.yang@linux.dev> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Wen Yang Monitors that instrument user-space function boundaries need to register uprobes and deregister them safely. Provide a thin wrapper so monitors share a single implementation of this boilerplate. struct rv_uprobe embeds struct uprobe_consumer directly, avoiding a separate heap allocation per probe. The struct holds an inode reference (acquired via igrab()) for the probed binary for the full uprobe lifetime, as uprobe_register() does not take an inode reference. On unregister, the inode reference is released with iput() only after rv_uprobe_unregister_sync(). rv_uprobe_unregister_sync() calls uprobe_unregister_sync(), draining all in-flight handlers before the containing struct may be freed. The API provides register, nosync unregister, a global handler barrier (rv_uprobe_unregister_sync), and an active-state predicate. Suggested-by: Gabriele Monaco Signed-off-by: Wen Yang --- include/rv/rv_uprobe.h | 35 +++++++++++++++++++++++ kernel/trace/rv/Kconfig | 4 +++ kernel/trace/rv/Makefile | 1 + kernel/trace/rv/rv_uprobe.c | 56 +++++++++++++++++++++++++++++++++++++ 4 files changed, 96 insertions(+) create mode 100644 include/rv/rv_uprobe.h create mode 100644 kernel/trace/rv/rv_uprobe.c diff --git a/include/rv/rv_uprobe.h b/include/rv/rv_uprobe.h new file mode 100644 index 000000000000..b93c2a81bc22 --- /dev/null +++ b/include/rv/rv_uprobe.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2026 Wen Yang */ +/* + * Generic uprobe infrastructure for RV monitors. + */ + +#ifndef _RV_UPROBE_H +#define _RV_UPROBE_H + +#include +#include + +struct inode; +struct pt_regs; + +/* + * Free the containing struct only after rv_uprobe_unregister_nosync() + + * rv_uprobe_unregister_sync() + iput(p->inode). + * + * The inode reference does not pin the dentry, so callers that re-resolve the + * probed path must hold a struct path: 9p cache=none remints an inode per + * lookup. + */ +struct rv_uprobe { + struct uprobe_consumer uc; + struct uprobe *uprobe; + struct inode *inode; +}; + +bool rv_uprobe_is_registered(const struct rv_uprobe *p); +int rv_uprobe_register(struct inode *inode, loff_t offset, struct rv_uprobe *p); +void rv_uprobe_unregister_nosync(struct rv_uprobe *p); +void rv_uprobe_unregister_sync(void); + +#endif /* _RV_UPROBE_H */ diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig index efa930f94ea4..2bc412304293 100644 --- a/kernel/trace/rv/Kconfig +++ b/kernel/trace/rv/Kconfig @@ -86,6 +86,10 @@ source "kernel/trace/rv/monitors/nomiss/Kconfig" # Add new monitors here +config RV_UPROBE + bool + depends on RV && UPROBES + config RV_REACTORS bool "Runtime verification reactors" default y diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile index 4b84b83b942b..8dc14a1819b8 100644 --- a/kernel/trace/rv/Makefile +++ b/kernel/trace/rv/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_RV_MON_DEADLINE) += monitors/deadline/deadline.o obj-$(CONFIG_RV_MON_NOMISS) += monitors/nomiss/nomiss.o obj-$(CONFIG_RV_MON_WAKEUP) += monitors/wakeup/wakeup.o # Add new monitors here +obj-$(CONFIG_RV_UPROBE) += rv_uprobe.o obj-$(CONFIG_RV_REACTORS) += rv_reactors.o obj-$(CONFIG_RV_REACT_PRINTK) += reactor_printk.o obj-$(CONFIG_RV_REACT_PANIC) += reactor_panic.o diff --git a/kernel/trace/rv/rv_uprobe.c b/kernel/trace/rv/rv_uprobe.c new file mode 100644 index 000000000000..1c7f8466aeed --- /dev/null +++ b/kernel/trace/rv/rv_uprobe.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic uprobe infrastructure for RV monitors. + */ +#include +#include +#include + +/* + * uprobe_register() takes no inode reference of its own, so grab one here and + * drop it only after rv_uprobe_unregister_sync(). + */ +int rv_uprobe_register(struct inode *inode, loff_t offset, struct rv_uprobe *p) +{ + int ret; + + p->inode = igrab(inode); + if (!p->inode) + return -ESTALE; + + p->uprobe = uprobe_register(inode, offset, 0, &p->uc); + if (IS_ERR(p->uprobe)) { + ret = PTR_ERR(p->uprobe); + p->uprobe = NULL; + iput(p->inode); + p->inode = NULL; + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(rv_uprobe_register); + +bool rv_uprobe_is_registered(const struct rv_uprobe *p) +{ + return p && p->uprobe; +} +EXPORT_SYMBOL_GPL(rv_uprobe_is_registered); + +/* The inode stays held: in-flight handlers may still reach it. */ +void rv_uprobe_unregister_nosync(struct rv_uprobe *p) +{ + if (!p || !p->uprobe) + return; + + uprobe_unregister_nosync(p->uprobe, &p->uc); + p->uprobe = NULL; +} +EXPORT_SYMBOL_GPL(rv_uprobe_unregister_nosync); + +/* Global barrier over every probe dequeued so far. */ +void rv_uprobe_unregister_sync(void) +{ + uprobe_unregister_sync(); +} +EXPORT_SYMBOL_GPL(rv_uprobe_unregister_sync); -- 2.25.1