From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA31CEF8FFA for ; Wed, 4 Mar 2026 15:42:51 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4fQxky1tCxz3c1J; Thu, 05 Mar 2026 02:42:50 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=213.95.11.211 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1772638970; cv=none; b=QUdoo9Zhd2luFnXvLRvj9bsh4O48u5zhcsD7Puv+12TtfHxq6Z9N21Vc2K0SqW/7QXa9aB7GuKMLepOnbxFjKftZ0QvgbPtxxruKOK00FVLqaI/l9hpvIQwYTuyJdcI6UX57YIWtk1X6PjJLtsmN6ohRxsMBLfN+Ds4fBuGPYB1V1xG0MdbKM9pK9dRm+VfVaVk8d8R034lilvNTIJnXQ3KvUP0Dn0407DhQtpUofb3rkE8z7PXpQEg16FN8vd5rIncVwHbXLNnLtVSYRmH5G0P3dj5oaqDkdWxyJPbpuk7OXMno9i1ZTLxJHlp6i7Cl3rmZ+35GTl4TeEJHPLMUDg== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1772638970; c=relaxed/relaxed; bh=dozotgLjCkx6YfloJbc2dUGdgLVASeazqMNufNecUOk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BJ4iIbMiVRtktVlH3XosOIZSgjW8ZJTUV88UA62tFxApxh2dIdekFKHgLOVrZUiR9WelyofLl2Rv+YPyyrafbFcnl+idbsrB8tyNbkF3L9vhg4Zp5UktP/CRrB+wjykHYPZWVXl+aXjtq9ehtX+WBWu3dYHgnBFxIMbnhY5Zy0o8371Ws6sWXnhyxccD7reVpJ3nfYbBNlCkkKkhOw4wXvuSshnLEgyL+Sh4gMA8eHe5HBTV1JBafBAv9eB/RCeMfjLAfutPMjalKt/TBQVzmfF/Mk3iliQ4kRU/tvh6RM7ZhD/buAZqj+TSUL90IXyyLJCL9B854OUjY6+gIF/HxA== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=lists.ozlabs.org) smtp.mailfrom=lst.de Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=lists.ozlabs.org) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4fQxkx3LMFz3btw for ; Thu, 05 Mar 2026 02:42:48 +1100 (AEDT) Received: by verein.lst.de (Postfix, from userid 2407) id 7375068AFE; Wed, 4 Mar 2026 16:42:41 +0100 (CET) Date: Wed, 4 Mar 2026 16:42:41 +0100 From: Christoph Hellwig To: Peter Zijlstra Cc: Christoph Hellwig , Eric Biggers , Andrew Morton , Richard Henderson , Matt Turner , Magnus Lindholm , Russell King , Catalin Marinas , Will Deacon , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , "David S. Miller" , Andreas Larsson , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Herbert Xu , Dan Williams , Chris Mason , David Sterba , Arnd Bergmann , Song Liu , Yu Kuai , Li Nan , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-crypto@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-arch@vger.kernel.org, linux-raid@vger.kernel.org Subject: Re: [PATCH 01/25] xor: assert that xor_blocks is not called from interrupt context Message-ID: <20260304154241.GA26451@lst.de> References: <20260226151106.144735-1-hch@lst.de> <20260226151106.144735-2-hch@lst.de> <20260227142455.GG1282955@noisy.programming.kicks-ass.net> <20260303160050.GB7021@lst.de> <20260303195517.GC2846@sol> <20260304145134.GA21983@lst.de> <20260304151548.GN1395266@noisy.programming.kicks-ass.net> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260304151548.GN1395266@noisy.programming.kicks-ass.net> User-Agent: Mutt/1.5.17 (2007-11-01) On Wed, Mar 04, 2026 at 04:15:48PM +0100, Peter Zijlstra wrote: > On Wed, Mar 04, 2026 at 03:51:34PM +0100, Christoph Hellwig wrote: > > > > How about "WARN_ON_ONCE(!preemptible())"? I think that covers the union > > > of the context restrictions correctly. (Compared to in_task(), it > > > handles the cases where hardirqs or softirqs are disabled.) > > > > Good enough I guess. Peter? > > Sure. The only caveat with that is that for PREEMPT_COUNT=n this might > not work, it unconditionally returns 0. That's a pretty good argument for the lockdep version...