• Max Filippov's avatar
    xtensa: don't allow overflow/underflow on unaligned stack · 3cfc096e
    Max Filippov authored
    Double exceptions that happen during register window overflow/underflow
    are handled in the topmost stack frame, as if it was the only exception
    that occured. However unaligned access exception handler is special
    because it needs to analyze instruction that caused the exception, but
    the userspace instruction that triggered window exception is completely
    irrelevant. Unaligned data access is rather normal in the generic
    userspace code, but stack pointer manipulation must always be done by
    architecture-aware code and thus unaligned stack means a serious problem
    Use the default unaligned access handler that raises SIGBUS in case
    of unaligned access in window overflow/underflow handler.
    Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>