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That's all we know. 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=ham 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: "Daniel P. Berrange" , "Michael S. Tsirkin" , Markus Armbruster , Juan Quintela , "Dr. David Alan Gilbert" , qemu-devel@nongnu.org, Alex Williamson , Stefan Hajnoczi , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Paolo Bonzini , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Steven Sistare writes: > On 7/30/2020 1:03 PM, Alex Benn=C3=A9e wrote: >>=20 >> Steve Sistare writes: >>=20 >>> Provide the -pause command-line parameter and the QEMU_PAUSE environment >>> variable to briefly pause QEMU in main and allow a developer to attach = gdb. >>> Useful when the developer does not invoke QEMU directly, such as when u= sing >>> libvirt. >>=20 >> How does this differ from -S? > > The -S flag runs qemu to the main loop but does not start the guest. Lot= s of code > that you may need to debug runs before you get there. Right - so this is for attaching a debugger to QEMU itself, not using the gdbstub? Why isn't this a problem the calling entity can solve by the way it invoked QEMU? We have similar sort of solutions for debugging our testcases: https://wiki.qemu.org/Features/QTest#Using_debugging_tools_under_the_test= _harness I still think: >>> +DEF("pause", HAS_ARG, QEMU_OPTION_pause, \ >>> + "-pause secs Pause for secs seconds on entry to main.\n", QEMU_= ARCH_ALL) >>> + >>> +SRST >>> +``--pause secs`` >>> + Pause for a number of seconds on entry to main. Useful for attach= ing >>> + a debugger after QEMU has been launched by some other entity. >>> +ERST >>> + >>=20 >> It seems like having an option to race with the debugger is just asking >> for trouble. this make the option problematic. --=20 Alex Benn=C3=A9e