• Jason Wessel's avatar
    kgdb, x86, arm, mips, powerpc: ignore user space single stepping · d7161a65
    Jason Wessel authored
    On the x86 arch, user space single step exceptions should be ignored
    if they occur in the kernel space, such as ptrace stepping through a
    system call.
    
    First check if it is kgdb that is executing a single step, then ensure
    it is not an accidental traversal into the user space, while in kgdb,
    any other time the TIF_SINGLESTEP is set, kgdb should ignore the
    exception.
    
    On x86, arm, mips and powerpc, the kgdb_contthread usage was
    inconsistent with the way single stepping is implemented in the kgdb
    core.  The arch specific stub should always set the
    kgdb_cpu_doing_single_step correctly if it is single stepping.  This
    allows kgdb to correctly process an instruction steps if ptrace
    happens to be requesting an instruction step over a system call.
    Signed-off-by: default avatarJason Wessel <jason.wessel@windriver.com>
    d7161a65
kgdb.c 38.4 KB