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Iglesias" References: <20251106145209.1083998-1-peter.maydell@linaro.org> <20251106145209.1083998-2-peter.maydell@linaro.org> Content-Language: en-US From: =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= In-Reply-To: <20251106145209.1083998-2-peter.maydell@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2a00:1450:4864:20::544; envelope-from=philmd@linaro.org; helo=mail-ed1-x544.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, 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-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org On 6/11/25 15:52, Peter Maydell wrote: > The documentation of the Xilinx DisplayPort subsystem at > https://www.xilinx.com/support/documents/ip_documentation/v_dp_txss1/v3_1/pg299-v-dp-txss1.pdf > doesn't say what happens if a guest tries to issue an AUX write > command with a length greater than the amount of data in the AUX > write FIFO, or tries to write more data to the write FIFO than it can > hold, or issues multiple commands that put data into the AUX read > FIFO without reading it such that it overflows. > > Currently QEMU will abort() in these guest-error situations, either > in xlnx_dp.c itself or in the fifo8 code. Make these cases all be > logged as guest errors instead. We choose to ignore the new data on > overflow, and return 0 on underflow. This is in line with how we handled > the "read from empty RX FIFO" case in commit a09ef5040477. > > Cc: qemu-stable@nongnu.org > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1418 > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1419 > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1424 > Signed-off-by: Peter Maydell > --- > hw/display/xlnx_dp.c | 28 ++++++++++++++++++++++++++-- > 1 file changed, 26 insertions(+), 2 deletions(-) Reviewed-by: Philippe Mathieu-Daudé