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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 00270EF8FEE for ; Wed, 4 Mar 2026 14:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=7OwA86SnZzNUGB3TVCWM5+M7FjnAjt0P/s/l7EZvY0k=; b=L8JMk2b7P1gO26aKsjq7UY53Dh CmK8vJv097sDSR7i1vU7hvNYHZhWJ9BYA/uluwYENwRKy6YKKKii6xQYI6IVLx1fkcn3YGRcvDieb E1vjg6WiYhXAVZTyxRVlEtRhgQD/bqvjVL182p99LZMSqml9bUufao3AbAvQj9yejJHRqQwr2C0kW oWjtpsvrQfWRH8WHzB9MPFACpFeZk8zWkRzKTNK5KLSdf7WxkJrnChSdwcTR3RaIQzFMOmnxnLdII q4wMw0Hge6N8Ff0KNScNyZvKjZZtI+xr0XCQlYtFrCJ9GUTin4niJ8KceyAbzJ7LrNxBQjCaysS44 lsFKt1pQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vxnZp-0000000HRep-1TQS; Wed, 04 Mar 2026 14:51:53 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vxnZm-0000000HReC-1szs; Wed, 04 Mar 2026 14:51:51 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 23B5068AFE; Wed, 4 Mar 2026 15:51:35 +0100 (CET) Date: Wed, 4 Mar 2026 15:51:34 +0100 From: Christoph Hellwig To: Eric Biggers Cc: Christoph Hellwig , Peter Zijlstra , 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: <20260304145134.GA21983@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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260303195517.GC2846@sol> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260304_065150_635309_6D8539B8 X-CRM114-Status: GOOD ( 14.87 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On Tue, Mar 03, 2026 at 11:55:17AM -0800, Eric Biggers wrote: > may_use_simd() is the "generic" way to check "can the FPU/vector/SIMD > registers be used". However, what it does varies by architecture, and > it's kind of a questionable abstraction in the first place. It's used > mostly by architecture-specific code. Yeah, I don't think that is quite right here. > 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?