From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 8AF50219A7A; Tue, 9 Dec 2025 12:56:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765284993; cv=none; b=qNhAoUEADbI0Yt1gdMtb8EZ0tFvDlMK2lSA14osb+GprkGmHWwQ4ePLXXwp4qDO82dB3NB3NX7agwCKAaVKr5LNGvHrQFK/IRkfR95HsxGk9VMkvxabw0tk6hCIdcP2BR4dncZ2zEfIHZvsnYgjoN7cMiWo1tp96uMPkMeks2eM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765284993; c=relaxed/simple; bh=RR3bt6P8iXOXnJ8uTIIhtA9Alxmrv+rTSCnJlYb4rp8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=K210KoF0pyX1kM8xD3c3FQwNeFIVOJN7gWuF4F71e8yFoKW+a/+PLd6Mf4xGjyNjFYqPC3kJqOvXs5bY4caOu8k1GuUBGVPCj5miexdQmvGB1srvEimtI0GwEjg2yD1TS9KpMzermeHoqNsIuBOh60JONYn7JfoDLfTwFzs32S4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=oSZzWTUJ; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="oSZzWTUJ" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=La44+vrPSRf6tLBZN9WnRWCtbw7U44CROD2xiC1F494=; b=oSZzWTUJ+ILbvWzS/amPsC+PUi qro4YvhqKu7S7QecGqIAkvmfdQMKgxQ0wxRoQd0RUbR8ipG8/i0bPqh/Dx0DxLAV3xBo+9kmPzUqq a69382req6TxIZvVcI9ZMaXscgQwQwRVDlnzfd/HwzR01ahaduath5YPXYF47IQn2jNiJqslmn69c PlxOqgGgd9WFRC/WP1ZmXlariUjltbYGFWw5W8JS8DYJZUgKnvcjKVr/hz5h6Ltl31/z21boDYgiH jTy3vPBWCKclM8hcQOuxdzUTMgIy4OUqK0lDhFbOLgybzHBINqtpN0XNQix9OZ7SOxxZ63sH/exO9 v1KTtU2w==; Received: from 2001-1c00-8d85-5700-266e-96ff-fe07-7dcc.cable.dynamic.v6.ziggo.nl ([2001:1c00:8d85:5700:266e:96ff:fe07:7dcc] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vSwOz-0000000Bm12-3ria; Tue, 09 Dec 2025 12:01:10 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 5B81130045C; Tue, 09 Dec 2025 13:56:27 +0100 (CET) Date: Tue, 9 Dec 2025 13:56:27 +0100 From: Peter Zijlstra To: Heiko Carstens Cc: Alexander Gordeev , Sven Schnelle , Vasily Gorbik , Christian Borntraeger , Mark Rutland , Arnd Bergmann , Jens Remus , Stefan Schulze Frielinghaus , Juergen Christ , linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH 0/9] s390: Exception based WARN() / WARN_ONCE() Message-ID: <20251209125627.GG3707837@noisy.programming.kicks-ass.net> References: <20251209121701.1856271-1-hca@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251209121701.1856271-1-hca@linux.ibm.com> On Tue, Dec 09, 2025 at 01:16:52PM +0100, Heiko Carstens wrote: > Use the generic infrastructure introduced by Peter Zijlstra [1] to implement > an exception based WARN() and WARN_ONCE() similar to x86. > > Due to some compiler oddities on s390 this requires to raise the minimum gcc > version to 9. Maybe there are ways to avoid this, but I failed to find a > working solution. Details are in the patch descriptions. > > Just posting this now to also get some compile bot testing, since I'm afraid > there might be some compiler version / config option around where even this > new approach breaks. > > Peter, since you were wondering: your generic infrastructure pieces work very > nice. Looking at the x86 and s390 implementation: it might be possible to make > things even more generic since both __WARN_printf(), and WARN_ONCE() are > identical; it looks like only __WARN_print_arg() needs to be provided. Nice! and yeah, perhaps we can unify that later.