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To: Linux List Kernel Mailing Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi folks! I have a question. What happens when dd writes data to a missing device? For example: # dd if=/home/mikhail/Downloads/Fedora-Workstation-Live-x86_64-Rawhide-20201010.n.0.iso of=/dev/adb Today I and wrongly entered /dev/adb instead of /dev/sdb, and what my surprise was when the data began to be written to the /dev/adb device without errors. But my surprise was even greater when cat /dev/adb started to display the written data. I have a question: Where the data was written and could it damage the stored data in memory or on disk? -- Best Regards, Mike Gavrilov.