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Fri, 05 Mar 2021 17:27:40 -0800 (PST) Received: from [192.168.1.11] ([71.212.131.83]) by smtp.gmail.com with ESMTPSA id w26sm1423803pge.23.2021.03.05.17.27.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 05 Mar 2021 17:27:39 -0800 (PST) Subject: Re: [PATCH v1 3/3] semihosting/arg-compat: fix up handling of SYS_HEAPINFO To: Keith Packard , Peter Maydell References: <20210305135451.15427-1-alex.bennee@linaro.org> <20210305135451.15427-4-alex.bennee@linaro.org> <87im65gxla.fsf@keithp.com> <877dmlgnrf.fsf@keithp.com> From: Richard Henderson Message-ID: <91d57887-8a5b-a837-6027-3fc2c38c48c7@linaro.org> Date: Fri, 5 Mar 2021 17:27:37 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <877dmlgnrf.fsf@keithp.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::42a; envelope-from=richard.henderson@linaro.org; helo=mail-pf1-x42a.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bug 1915925 <1915925@bugs.launchpad.net>, "open list:ARM TCG CPUs" , =?UTF-8?Q?Alex_Benn=c3=a9e?= , QEMU Developers Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 3/5/21 3:54 PM, Keith Packard via wrote: > I don't know of any implementation in hardware or software that supports > modifying this value. I'm not sure we need to support this in the > semihosting code for qemu as I'm pretty sure getting qemu to support > dynamic XLEN values would be a large project I think it would be fairly trivial, now. We have riscv_cpu_is_32bit (which checks misa, not xlen, fwiw). It's not examined in cpu_get_tb_cpu_state(), but it is many other places. > (a project which I don't > personally feel would offer much value). Now that's a different story. I'll take no position there. However! We do have a function, that can be made into a TCG hook, which could then be queried by semihosting/. r~