From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (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 4D3FE29ACE5 for ; Mon, 20 Oct 2025 20:31:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760992300; cv=none; b=UkbQHzKLnDDsxCMv8EGeqr51DpmLh3wFLveH87QLj2cHuBLlg/CpmTaBerpUYwUzdyEiz5gOe07LibLuKlwDpMjpDZRZu6ToGKYvVXESwr9EHOtFt/j6AnjmjxHhUztMHjT2laJ9fsx1kVsRTJH+Ayri+Ya1zaAHqcbVu10odtg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760992300; c=relaxed/simple; bh=kwQ5mRWhqn3KwbVVEu6HMiVDjmpj/6heHOhp0mrszhI=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=WArcaK3uIs1/mfElokUiMfRSBwBJ2qH3+0iq5uIhyPGhukloCk9MXfuXANbbhiAYo+BMFo8Ejf5GGWOgMMLEz320lXYNw9bk+KbHYZy3b5tbWVKisqaR6huel1CXRMSADCB1GBfgTuXyrS8hzlGRThrg0oZv1zMwoM7b3VWP8EU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 42E77853B6; Mon, 20 Oct 2025 20:31:31 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf11.hostedemail.com (Postfix) with ESMTPA id 565EC2002A; Mon, 20 Oct 2025 20:31:29 +0000 (UTC) Date: Mon, 20 Oct 2025 16:31:49 -0400 From: Steven Rostedt To: Song Liu Cc: Andrey Grodzovsky , Petr Mladek , "kernel-team@lists.ubuntu.com" , "live-patching@vger.kernel.org" Subject: Re: [External] Re: Question - Livepatch/Kprobe Coexistence on Ftrace-enabled Functions (Ubuntu kernel based on Linux stable 5.15.30) Message-ID: <20251020163149.1d7f2692@gandalf.local.home> In-Reply-To: References: <82eaaada-f3fc-44f7-826d-8de47ce9fd39@crowdstrike.com> <69339fb8-04a6-4c28-bb71-d9522ebd7282@crowdstrike.com> <4cc825e6-fdf8-4fc1-8ccd-9bad456c2131@crowdstrike.com> <5477a73a-1dce-4b9e-b389-e757ef5536c4@crowdstrike.com> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: live-patching@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: z9t1p3746jddjsga5ngo9w56zhq8et7m X-Rspamd-Server: rspamout05 X-Rspamd-Queue-Id: 565EC2002A X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+bPIGG/By3oBOFJ1S0YOEGkGDw9NXqvOU= X-HE-Tag: 1760992289-710706 X-HE-Meta: U2FsdGVkX19g0F7DSMC5QPZGOwHnpTa/7TSN2nbSeBoj3fegMi4+vHLWb2qb2in8emz0SLFYgs5aGdiYuX036cS0nuXCt+PuEX4vnE5UEd9XbEojcxrzpok+mF4xJikCAlHdJkw22b5+htRSdn3smiyfXsBl9zfTX5yFhdlVrqfFkguCN+emUg9j6HgQ/cLsDPs09yiQJVn4SGcMJV+fntLYNeN7sqD9ifCVWlQToW5R71Jg5u6MeNS295zLvijiDfTBzdbh77WIj2OX6XQG5jwT9X/9ynBhCUpfcY24YFEks9VbzfDo5l2X7CbJ2Feyu4HRqslmKp9vIjtX9EiT32oDVxIHubcimnaaI1aD6zI35+eZx6utlQ== On Mon, 20 Oct 2025 11:53:34 -0700 Song Liu wrote: > diff --git i/kernel/trace/ftrace.c w/kernel/trace/ftrace.c > index 42bd2ba68a82..8f320df0ac52 100644 > --- i/kernel/trace/ftrace.c > +++ w/kernel/trace/ftrace.c > @@ -6049,6 +6049,9 @@ int register_ftrace_direct(struct ftrace_ops > *ops, unsigned long addr) > > err = register_ftrace_function_nolock(ops); > > + if (err) > + remove_direct_functions_hash(hash, addr); > + > out_unlock: > mutex_unlock(&direct_mutex); > > > Steven, > > Does this change look good to you? With the small nit that you don't need a space between the err = and the if (err). But yeah, looks fine to me. -- Steve