Hello, There's a long-standing irritation in Xen, whereby printk()'s which occur prior to console_init_preirq() get half-lost.
They end up in the console ring, and hence are available via `xl dmesg`, but they're missing from serial console. e.g. these 4 lines don't escape (XEN) Enabling lockdown mode because Secure Boot is enabled (XEN) Lockdown mode is enabled (XEN) Ignoring cmdline option 'hap_2mb' in lockdown mode (XEN) Ignoring cmdline option 'hap_1gb' in lockdown mode __ __ _ _ _ ___ ____ \ \/ /___ _ __ | || | / |/ _ \ |___ \ This is from a testcase failure I've just debugged, but the issue is not specific to secureboot. More generally, any diagnostic from cmdline parsing ends up in this state. For PVShim, we did a gross hack to assume the PV console is usable right from the outset, but all other console configurations don't start working until the cmdline has been parsed. Is anything stopping us from feeding the current contents of the console ring into serial in console_init_preirq()? ~Andrew
