On Sat, 18 Sept 2021 at 09:12, Ali Vatankhah <alivatankha...@gmail.com> wrote: > then to check what instructions are executing I run this command: > > qemu-system-ppc64 -nographic -M ppce500 -cpu e5500 -kernel uImage -singlestep > -d in_asm -D target_asm.log > > Obviously this results in a Kernel panic, but the point is that after panic > there is no guest > instruction running as there is no more log in the file but still CPU usage > is 100.
The lack of further in_asm logging does not mean that guest instructions are not running. in_asm logging happens at *translate* time, which is to say the first time QEMU encounters any particular instruction. After translation, QEMU can re-execute the translated code for that instruction many times, and it will not show up in in_asm logs again. In particular, if the guest CPU is doing either of: * a tight loop * an infinite loop of taking exceptions it will just be re-running code that has been seen before. Probably the code the kernel runs after it panic()s is just a loop. If you want to log execution, you need to add 'exec' and/or 'cpu' to your -d logging. (Warning: this can generate a lot of logging output and massively slow down execution as a result.) > also run this command to check generated host assembly code: > > qemu-system-ppc64 -nographic -M ppce500 -cpu e5500 -kernel uImage -singlestep > -d out_asm -D host_asm.log out_asm also is logged only at translate time, not at execution time. -- PMM
