• Linus Torvalds's avatar
    x86: mm: consolidate VM_FAULT_RETRY handling · 26178ec1
    Linus Torvalds authored
    The VM_FAULT_RETRY handling was confusing and incorrect for the case of
    returning to kernel mode.  We need to handle the exception table fixup
    if we return to kernel mode due to a fatal signal - it will basically
    look to the kernel user mode access like the access failed due to the VM
    going away from udner it.  Which is correct - the process is dying - and
    avoids the whole "repeat endless kernel page faults" case.
    
    Handling the VM_FAULT_RETRY early and in just one place also simplifies
    the mmap_sem handling, since once we've taken care of VM_FAULT_RETRY we
    know that we can just drop the lock.  The remaining accounting and
    possible error handling is thread-local and does not need the mmap_sem.
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    26178ec1
fault.c 32.2 KB