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 565291E885F; Thu, 10 Oct 2024 19:48:34 +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=1728589714; cv=none; b=iDTupoffsgggkZS87q9OdpM5bohafWkNg/bN4TSXTgr80RQD+vZ3LDAbc1ptv++iqrQplpl1ZXQLkGLUPKQK2iRT7MI8Y2uRnf8xWtWURDavKT+yQqkouhv6ucAAxIKlb6wjSdCPN6acgBNYJRf/bM5LOMuUaQmveruuyduTY/Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728589714; c=relaxed/simple; bh=F2HPyfn7AS7sxdWUgbKoi+uuw+6C/R/lmzaG67e9Seo=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aVTtzOUI8mtnLRG5zx76nVkEQ/o4Jfit1XQsYr/fCSv/Gc6c1hDPCMpYO0aaVwhveuwcxtsAe5LCyp2vQBOCqLKG1ob0159Nxzu3GIQWO46N/zOxcKK2msZYTF0LH0XgfAIDNwmOcm1EWcqpOrzWg3qKkLJ9hvtn41oJy8ODfpc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85BC2C4CED5; Thu, 10 Oct 2024 19:48:32 +0000 (UTC) Date: Thu, 10 Oct 2024 15:48:40 -0400 From: Steven Rostedt To: Josh Poimboeuf Cc: "James E.J. Bottomley" , Helge Deller , linux-kernel@vger.kernel.org, Sven Schnelle , linux-trace-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, Masami Hiramatsu , Mark Rutland , Peter Zijlstra Subject: Re: [PATCH] parisc/ftrace: Fix function graph tracing disablement Message-ID: <20241010154840.6e158c78@gandalf.local.home> In-Reply-To: <5962b9e161b2b9296509c3d65c7f16c11b07bd16.1727904678.git.jpoimboe@kernel.org> References: <5962b9e161b2b9296509c3d65c7f16c11b07bd16.1727904678.git.jpoimboe@kernel.org> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 2 Oct 2024 14:32:04 -0700 Josh Poimboeuf wrote: > Due to an apparent copy-paste bug, the parisc implementation of > ftrace_disable_ftrace_graph_caller() doesn't actually do anything. It > enables the (already-enabled) static key rather than disabling it. > > The result is that after function graph tracing has been "disabled", any > subsequent (non-graph) function tracing will inadvertently also enable > the slow fgraph return address hijacking. > > Fixes: 98f2926171ae ("parisc/ftrace: use static key to enable/disable function graph tracer") > Signed-off-by: Josh Poimboeuf > --- > arch/parisc/kernel/ftrace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/parisc/kernel/ftrace.c b/arch/parisc/kernel/ftrace.c > index c91f9c2e61ed..f8d08eab7db8 100644 > --- a/arch/parisc/kernel/ftrace.c > +++ b/arch/parisc/kernel/ftrace.c > @@ -87,7 +87,7 @@ int ftrace_enable_ftrace_graph_caller(void) > > int ftrace_disable_ftrace_graph_caller(void) > { > - static_key_enable(&ftrace_graph_enable.key); > + static_key_disable(&ftrace_graph_enable.key); > return 0; > } > #endif Awfully quite :-/ I wonder if anyone cares about parisc today? Hmm. -- Steve