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Tue, 01 Dec 2020 08:12:31 +0000 MIME-Version: 1.0 Date: Tue, 01 Dec 2020 08:12:30 +0000 From: Marc Zyngier To: wangrongwei Subject: Re: [PATCH 0/3] arm64:msr: Add MSR driver In-Reply-To: <855BA92C-5B22-4F14-965A-B1F72A872B8D@linux.alibaba.com> References: <20201130174833.41315-1-rongwei.wang@linux.alibaba.com> <5e7f7225982b2df63e62ea60ec632376@misterjones.org> <855BA92C-5B22-4F14-965A-B1F72A872B8D@linux.alibaba.com> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <059ed4a8768ff3881005796cb4a10d5e@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: rongwei.wang@linux.alibaba.com, catalin.marinas@arm.com, will@kernel.org, bjorn.andersson@linaro.org, shawnguo@kernel.org, gshan@redhat.com, geert+renesas@glider.be, Anson.Huang@nxp.com, masahiroy@kernel.org, michael@walle.cc, krzk@kernel.org, linux-kernel@vger.kernel.org, vkoul@kernel.org, olof@lixom.net, vincenzo.frascino@arm.com, ardb@kernel.org, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201201_031234_767099_C87E3EFB X-CRM114-Status: GOOD ( 12.43 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: vkoul@kernel.org, gshan@redhat.com, Anson.Huang@nxp.com, geert+renesas@glider.be, catalin.marinas@arm.com, masahiroy@kernel.org, linux-kernel@vger.kernel.org, krzk@kernel.org, bjorn.andersson@linaro.org, michael@walle.cc, olof@lixom.net, shawnguo@kernel.org, vincenzo.frascino@arm.com, Will Deacon , ardb@kernel.org, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2020-12-01 03:09, wangrongwei wrote: > Hi > We have validate this driver in vm and physical machine, and works > fine. But what does "work fine" mean? None of these system registers are supposed to be accessible from userspace, so please explain *what* you are trying to do with this, other that introducing security holes and general system instability? > Actually, we used existing interfaces to realize this driver, likes > aarch64_insn_read and aarch64_insn_patch_text. Sure. At that stage, you could also directly expose the linear mapping to userspace and start writing to it, it would probably be a fitting addition... > These existing intefaces had validated a CPU. If CPU validation is your goal, I suggest this is kept out of tree, as the kernel is hardly a validation tool for the arm64 architecture. Thanks, M. -- Jazz is not dead. It just smells funny... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel