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 1FD8F20DD51 for ; Fri, 4 Sep 2026 23:06:40 +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=1788563203; cv=none; b=J16DOahHE5ku0oxXlcRkZuk9jH0FAxYks6Iemp4y/7DHkGLXZaN/BRuLq5DJ0iYMkgrv8iaIoyG3nsrtEZZ39hYd3oMiCKIYlNq9jaWA0QBdCyiGcwRLKojdYQGe4Xqk2bcKaknm9WGUTaA2ixIkPBdQiEjRQc+3IhU5z3tdo9g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788563203; c=relaxed/simple; bh=/2B8Dh2/jbEdAtdLQ1sAD0zdFqbOW1Rz7xO7wTEh/Bw=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=C2kK23F5vkTNu9tMjmuouYR30iE/ANMMUKnmbtN1XgnP9aKWixBcO10AJMthYFOwg6YKAfW4y/dMB7CVkCZj7FPlwEHUtxikqO973tN9dnmsF6ulXMmgWEhr/0uWQ3YaJEjFIL4UXGTYSS4FoAv8xquuFAs20Wjzt8HaaXJZZf8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; dkim=pass (1024-bit key) header.d=goodmis.org header.i=@goodmis.org header.b=CQPmXmvz; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=goodmis.org header.i=@goodmis.org header.b="CQPmXmvz" Received: from omf08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id C6228A3E91; Fri, 4 Sep 2026 23:06:38 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf08.hostedemail.com (Postfix) with ESMTPA id 9A16B20027; Fri, 4 Sep 2026 23:06:36 +0000 (UTC) Date: Fri, 4 Sep 2026 19:07:42 -0400 From: Steven Rostedt To: Thomas Gleixner Cc: Ye Liu , "Peter Zijlstra (Intel)" , Marco Elver , Ye Liu , Yi Tao , Tejun Heo , Bart Van Assche , Christian Brauner , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/8] mm: introduce for_each_process_rcu and for_each_thread_rcu Message-ID: <20260904190742.7231d56e@gandalf.local.home> In-Reply-To: <87ecf87m31.ffs@fw13> References: <20260904083001.553587-1-ye.liu@linux.dev> <20260904083001.553587-2-ye.liu@linux.dev> <20260904122536.1079b279@gandalf.local.home> <87ecf87m31.ffs@fw13> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-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 X-Rspamd-Queue-Id: 9A16B20027 X-Stat-Signature: 94599w63qsp378ifyksoajqeyc94b7t5 X-Rspamd-Server: rspamout03 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1/GwGttuyOnfaOFMG/Hbl+emC5UFLFYKaQ= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=goodmis.org; h=date:from:to:cc:subject:message-id:in-reply-to:references:mime-version:content-type:content-transfer-encoding; s=dkim1; bh=rc4fok4nFu4VvpijLSYYc3rMm1OuQylSLRygVzKrmI4=; b=CQPmXmvzu/I8VbxcdHi6InpOHSFT+cKnx2hNKizzJSRb7eTVePzevf3AOUyk24lc7PX/J5V4oDfjBi2qaiV+hJ77yqH35qtCv3dmnHaEIyU2ar+urRyuX2T3Vx6dbDc5jS6e4C2UIRoo8QbOwq3tfmfn4IuJQFueyegTZ1Zd/FY= X-HE-Tag: 1788563196-903902 X-HE-Meta: U2FsdGVkX18jc21xB9g4cXGD+ND4k+RwPmOPv/s7f+mILwVw57ZmBTuWjhcGewzIyfbliww94R12rQUH+Jay427ObIq4st0GytjwRczpNJTekbQPeBdLgmqV26Dtu9bEoIbaEXFpk3AmK4V/JExEZ5jNXpP5qgehBgZjbr6qt7vrHyiNcYZ8Laz+kLmHMh6nTsZEa9L9K9/qFhmmbdz+5JD8Xu+/HfHfuHE8Av1n/vmTzLdD5qyV+f7OW1L6anG3KRJ6hj/H3JbE2jXHlu5QZEWSoBDAJbjDiy7Q9F12Mnkr5w/xE66C9XFBVpqCKmQ8kyHYqLFAZ4g4pEVSPfLfo64OrIzO3yxt On Fri, 04 Sep 2026 23:17:38 +0200 Thomas Gleixner wrote: > No. Scopes can be left by any valid termination mechanism. > > The only problematic case of leaving a scoped_guard() with goto is when > the goto is actually implemented as an ASM goto. See the comment above > arch_unsafe_get_user() in linux/uaccess.h. Oh OK. I was under the impression that goto's could cause undefined behavior with guards. Or is that just when a goto jumps over one? Or is that OK too? -- Steve