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 0E872C3DA70 for ; Tue, 30 Jul 2024 15:35:35 +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=uhPFJb62DFCsxit5TLMPFch79DbpaM3TaP3BiBTJhN4=; b=nwJx/OQhuXUtijJtdwuWAzv5Vv LkMPnsq8Ri0W2BsWVkKVSyqY2iHtSRmmeMAxCiF8eNr631SQ/yegOgzRIMXGIYQoxuCyA9d5/dj1b NMzHCUUiBKMRDi+siLa9DlmdnvsDlp/2UQuyzE/Ryt9hWYoeMiAbREmcjipiyohd/vXNy6sKX47qU yJKk6athU7YRbn7XDdHm+W/uXtyFdclWv3wEjuCBorG643hiuzwY9EQsHF4iZp39CcKiY6ba7KvsK Fsply7sAHsCFvu6FUWxU1xc6BQMXNHpL36GMctRfffa26bYl20UxNU6rHawSdcg/CimS91A+JW7g1 /3rKCfEw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sYosl-0000000FgD5-3aRY; Tue, 30 Jul 2024 15:35:23 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sYosJ-0000000Fg6l-1s0J for linux-arm-kernel@lists.infradead.org; Tue, 30 Jul 2024 15:34:56 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 2202D68AA6; Tue, 30 Jul 2024 17:34:51 +0200 (CEST) Date: Tue, 30 Jul 2024 17:34:50 +0200 From: Christoph Hellwig To: Nathan Chancellor Cc: kernel test robot , Baruch Siach , Christoph Hellwig , Marek Szyprowski , Catalin Marinas , Will Deacon , llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev, linux-s390@vger.kernel.org, Ramon Fried , Petr =?utf-8?B?VGVzYcWZw61r?= , Robin Murphy , linux-kernel@vger.kernel.org, iommu@lists.linux.dev, Elad Nachman , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3 2/3] dma-mapping: replace zone_dma_bits by zone_dma_limit Message-ID: <20240730153450.GA30021@lst.de> References: <053fa4806a2c63efcde80caca473a8b670a2701c.1722249878.git.baruch@tkos.co.il> <202407300338.oaUo6jtB-lkp@intel.com> <20240730021208.GA8272@thelio-3990X> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240730021208.GA8272@thelio-3990X> 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-20240730_083455_647594_FC462BB5 X-CRM114-Status: GOOD ( 17.68 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jul 29, 2024 at 07:12:08PM -0700, Nathan Chancellor wrote: > > | ~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~ > > include/linux/dma-mapping.h:77:40: note: expanded from macro 'DMA_BIT_MASK' > > 77 | #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) > > | ^~~~~ > > 2 warnings generated. > > FWIW, this is likely a false positive due to an issue in Clang with the > control flow graph for global variables: > > https://github.com/ClangBuiltLinux/linux/issues/92 > > DMA_BIT_MASK() has been the biggest offender :/ If there is any way to > refactor this code to avoid this, that would be great (as that has been > one of our longest outstanding issues and getting it fixed in the > compiler does not seem super easy at this point). I have no idea what you'd want changed here, but I'll happily take patches.