From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 1/3] csky: Fixup arch_get_unmapped_area() implementation Date: Tue, 20 Aug 2019 19:16:50 -0700 Message-ID: <20190821021650.GA32710@infradead.org> References: <1566304469-5601-1-git-send-email-guoren@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1566304469-5601-1-git-send-email-guoren@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: guoren@kernel.org Cc: arnd@arndb.de, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-csky@vger.kernel.org, douzhk@nationalchip.com, Guo Ren List-Id: linux-arch.vger.kernel.org > +/* > + * We need to ensure that shared mappings are correctly aligned to > + * avoid aliasing issues with VIPT caches. We need to ensure that > + * a specific page of an object is always mapped at a multiple of > + * SHMLBA bytes. > + * > + * We unconditionally provide this function for all cases. > + */ On something unrelated: If csky has virtually indexed caches you also need to implement the flush_kernel_vmap_range and invalidate_kernel_vmap_range functions to avoid data corruption when doing I/O on vmalloc/vmap ranges. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.133]:53776 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726512AbfHUCQy (ORCPT ); Tue, 20 Aug 2019 22:16:54 -0400 Date: Tue, 20 Aug 2019 19:16:50 -0700 From: Christoph Hellwig Subject: Re: [PATCH 1/3] csky: Fixup arch_get_unmapped_area() implementation Message-ID: <20190821021650.GA32710@infradead.org> References: <1566304469-5601-1-git-send-email-guoren@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1566304469-5601-1-git-send-email-guoren@kernel.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: guoren@kernel.org Cc: arnd@arndb.de, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-csky@vger.kernel.org, douzhk@nationalchip.com, Guo Ren Message-ID: <20190821021650.EZU97HeIrz7W1kQ7oiADz6whTkKVcLEWDUg4uhXKeK4@z> > +/* > + * We need to ensure that shared mappings are correctly aligned to > + * avoid aliasing issues with VIPT caches. We need to ensure that > + * a specific page of an object is always mapped at a multiple of > + * SHMLBA bytes. > + * > + * We unconditionally provide this function for all cases. > + */ On something unrelated: If csky has virtually indexed caches you also need to implement the flush_kernel_vmap_range and invalidate_kernel_vmap_range functions to avoid data corruption when doing I/O on vmalloc/vmap ranges.