Does this still happen on 5.1-rc2? Do you have idea as to what max_low_pfn() gets set to on your system at boot time? >From the screen shot I'm guessing it MIGHT be 0x373fe, but it's hard to know for sure. > On Mar 21, 2019, at 2:22 PM, Meelis Roos <mroos@xxxxxxxx> wrote: > > I tried to debug another problem and turned on most debug options for memory. > The resulting kernel failed to boot. > > Bisecting the configurations led to CONFIG_DEBUG_VIRTUAL - if I turned it on > in addition to some other debug options, the machine crashed with > > kernel BUG at arch/x86/mm/physaddr.c:79! > > Screenshot at http://kodu.ut.ee/~mroos/debug_virtual-boot-hang-1.jpg > > The machine was Athlon XP with VIA KT600 chipset and 2G RAM. > > -- > Meelis Roos <mroos@xxxxxxxx> >