• Michael Neuling's avatar
    powerpc/64s: Clear PCR on boot · faf37c44
    Michael Neuling authored
    Clear the PCR (Processor Compatibility Register) on boot to ensure we
    are not running in a compatibility mode.
    
    We've seen this cause problems when a crash (and kdump) occurs while
    running compat mode guests. The kdump kernel then runs with the PCR
    set and causes problems. The symptom in the kdump kernel (also seen in
    petitboot after fast-reboot) is early userspace programs taking
    sigills on newer instructions (seen in libc).
    Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    faf37c44
dt_cpu_ftrs.c 25 KB