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See http://www.infradead.org/rpr.html Cc: Vignesh Raghavendra , linux-pci@vger.kernel.org, linux-fpga@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-ide@vger.kernel.org, linux-mtd@lists.infradead.org, linux-i2c@vger.kernel.org, Miquel Raynal , linux-rdma@vger.kernel.org, Richard Weinberger , Joerg Roedel , linux-atm-general@lists.sourceforge.net, trix@redhat.com, Jakub Kicinski , linux-kernel-mentees@lists.linuxfoundation.org, Wolfgang Grandegger , intel-gfx@lists.freedesktop.org, linux-gpio@vger.kernel.org, Borislav Petkov , Kalle Valo , linux-edac@vger.kernel.org, linux-hwmon@vger.kernel.org, Saheed Bolarinwa , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-crypto@vger.kernel.org, netdev@vger.kernel.org, dmaengine@vger.kernel.org, Marc Kleine-Budde , "David S. Miller" Subject: Re: [Linux-kernel-mentees] [RFC PATCH 00/17] Drop uses of pci_read_config_*() return value X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" On Sun, Aug 02, 2020 at 02:14:06PM -0500, Bjorn Helgaas wrote: > But what guarantees that a PCI config register cannot contain ~0? > If there's something about that in the spec I'd love to know where it > is because it would simplify a lot of things. There isn't. An we even have cases like the NVMe controller memory buffer and persistent memory region, which are BARs that store abritrary values for later retreival, so it can't. (now those features have a major issue with error detection, but that is another issue) _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees