• Cyril Bur's avatar
    powerpc: Fix checkstop in native_hpte_clear() with lockdep · fdf880a6
    Cyril Bur authored
    native_hpte_clear() is called in real mode from two places:
    - Early in boot during htab initialisation if firmware assisted dump is
      active.
    - Late in the kexec path.
    
    In both contexts there is no need to disable interrupts are they are
    already disabled. Furthermore, locking around the tlbie() is only required
    for pre POWER5 hardware.
    
    On POWER5 or newer hardware concurrent tlbie()s work as expected and on pre
    POWER5 hardware concurrent tlbie()s could result in deadlock. This code
    would only be executed at crashdump time, during which all bets are off,
    concurrent tlbie()s are unlikely and taking locks is unsafe therefore the
    best course of action is to simply do nothing. Concurrent tlbie()s are not
    possible in the first case as secondary CPUs have not come up yet.
    Signed-off-by: default avatarCyril Bur <cyrilbur@gmail.com>
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    fdf880a6
machdep.h 10.8 KB