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make -C $(KDIR) FROM_DKMS=n NOSTDINC_FLAGS="$(ENOSTDINC_FLAGS)" M=$(CURDIR) modules EXTRA_CFLAGS="-g -O0 -fno-omit-frame-pointer"
Good luck debugging...
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Serial Console Tracing
Or you may not want to do any of that complicated mess above and you just want to have serial from the guest trace to a console. This does not involve building kernels or any of that.
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