From patchwork Fri Dec 20 17:41:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 13917212 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 EE191227BAB; Fri, 20 Dec 2024 17:47:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734716868; cv=none; b=mtmAP9NP+EOeCjt6roqSZ2wZbQDeV2JpRKsOsQNm6pTdX6TdXUasDjeDrbXnHJCWGDwvYWiWCBiihHAE5nqsXhM6iO7EymWGSmB8jEtz62/MC/3hbcpUWfFlZnmVD8ihTSspCh7As4CtNMDFEo56SdrDCBQdrVUlaxAm/w/zXIs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734716868; c=relaxed/simple; bh=ZCYpbinhL6uGHkLuSdwWLthc9rjMA4h7HhoINLswtfg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ph/TiwB6OhBGblGJg0eVSC9N2btHwGwZuKPm3kntx/HDZ9PSC4BPjnfVA31yIEDywY79/GD5ABSwSAG8msr9mKgHg8giAIX1onPISqjKG0RcVuCNSB/WI7cxBiZl5UBhvBMSP6f37dXWomXaCwUQ5Vm1yYXhEt7xOZVRWOzbThQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Dr+7RMQB; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=AZSx8zxz; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Dr+7RMQB"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="AZSx8zxz" From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1734716864; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8cOfqq93x0oPQPFrMlSeinUf1WhvLlURcCwn2/B9V34=; b=Dr+7RMQBSI0JHm4g6BniB6jZDFuoF+xofjsoJ8mUEF2oBm+1pGpYluIuQVawxnxclkoWaJ +HHeJBPpIxk7UerRguKKBX73oK4rTa/opx2cKh9HdBB6ModF7+KqAqvujSc+c8C7E/GEB2 2P2Z3sAj93+oQ9J0lHeDlAqnaBLZUnzWVGNB5byDwB7t2xlZvn00gNvuJb8rFdpBjx/nfJ nakdz1wMlCaf7VD5ufRxyM5CrLVZAFX5mCYHZEC0nBMOkhCqK6c7JGVPG2qOYxb23Iq8bI DxnpERqrc++5KxybwLFKL9NKo0xzTZE/KG4CUYbw2mnFxT7hApBL8P6Z7hhqLQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1734716864; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8cOfqq93x0oPQPFrMlSeinUf1WhvLlURcCwn2/B9V34=; b=AZSx8zxzXWRhcOocsxUzld2ZvnNF5RCFUWhKFiEwKDv3uSi2sPubKCRsLiteienIG1tdMy 8jLsoA1ckq2ECHCA== To: linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Daniel Gomez , Luis Chamberlain , "Paul E . McKenney" , Peter Zijlstra , Petr Pavlu , Sami Tolvanen , Thomas Gleixner , Sebastian Andrzej Siewior , Christophe Leroy , Madhavan Srinivasan , Mark Rutland , Masami Hiramatsu , Michael Ellerman , Naveen N Rao , Nicholas Piggin , Steven Rostedt , linux-trace-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 20/28] powerpc/ftrace: Use RCU in all users of __module_text_address(). Date: Fri, 20 Dec 2024 18:41:34 +0100 Message-ID: <20241220174731.514432-21-bigeasy@linutronix.de> In-Reply-To: <20241220174731.514432-1-bigeasy@linutronix.de> References: <20241220174731.514432-1-bigeasy@linutronix.de> Precedence: bulk X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 __module_text_address() can be invoked within a RCU section, there is no requirement to have preemption disabled. Replace the preempt_disable() section around __module_text_address() with RCU. Cc: Christophe Leroy Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Michael Ellerman Cc: Naveen N Rao Cc: Nicholas Piggin Cc: Steven Rostedt Cc: linux-trace-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Sebastian Andrzej Siewior --- arch/powerpc/kernel/trace/ftrace.c | 6 ++---- arch/powerpc/kernel/trace/ftrace_64_pg.c | 6 ++---- 2 files changed, 4 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index 5ccd791761e8f..558d7f4e4bea6 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -115,10 +115,8 @@ static unsigned long ftrace_lookup_module_stub(unsigned long ip, unsigned long a { struct module *mod = NULL; - preempt_disable(); - mod = __module_text_address(ip); - preempt_enable(); - + scoped_guard(rcu) + mod = __module_text_address(ip); if (!mod) pr_err("No module loaded at addr=%lx\n", ip); diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c index 98787376eb87c..531d40f10c8a1 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c @@ -120,10 +120,8 @@ static struct module *ftrace_lookup_module(struct dyn_ftrace *rec) { struct module *mod; - preempt_disable(); - mod = __module_text_address(rec->ip); - preempt_enable(); - + scoped_guard(rcu) + mod = __module_text_address(rec->ip); if (!mod) pr_err("No module loaded at addr=%lx\n", rec->ip);