Debugging with Qemu
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> Get this KVM qcow2 image
KVM = Kernel Virtual Machine based on wp:QEMU (https://QEMU.org). File is an wp:Xz-compressed (like 7-zip; only GPL) "debug-crash.qcow"
So, I installed QEMU + dependencies
> Please show the commands you use to start via libvirt with this XML.
The xml had /usr/bin/kvm-spice
in it as the emulator; so I searched dpkg -S /usr/bin/kvm-spice
which turns out to be qemu-kvm (that I already have installed). So I assume that I'll need to run qemu-kvm. So then I researched how to start a qemu-kvm session/machine, using libvirt, and given an XML manifest / configuration file.
To login use - User: ubuntu - Password: ubuntu - SSH server runs by default and guest does dhcp (or use the serial console) In that image clarify the following things: - Apache is not starting, why? - What is going on with /var/crash/_usr_sbin_postconf.1000.crash (use debug symbols and apport-retrace / apport-unpack to get started) Makefile Weirdness It was determined that a certain linker flag was causing problems in the build of a package, so a change was added to debian/rules to remove that flag: override_dh_auto_build: CFLAGS="$(CFLAGS) $(CPPFLAGS)" \ LDFLAGS="$(dpkg-buildflags --get LDFLAGS \ | sed -e 's/-Wl,-Bsymbolic-functions//')" \ dh_auto_build The flag was removed from LDFLAGS via a simple sed expression. It turns out this change actually made LDFLAGS empty. Why?