On Mon, Jan 04, 2016 at 12:19:53PM +0100, Dominik Dingel wrote: > Hello, > > sorry for the delay since the last version. > > During Jasons work with postcopy migration support for s390 a problem regarding > gmap faults was discovered. > > The gmap code will call fixup_user_fault which will end up always in > handle_mm_fault. Till now we never cared about retries, but as the userfaultfd > code kind of relies on it. this needs some fix. > > This patchset does not take care of the futex code. I will now look closer at > this. > > Thanks, > Dominik > > v2 -> v3: > - In case of retrying check vma again > - Do the accounting of major/minor faults once Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> > > v1 -> v2: > - Instread of passing the VM_FAULT_RETRY from fixup_user_fault we do retries > within fixup_user_fault, like get_user_pages_locked do. > - gmap code will now take retry if fixup_user_fault drops the lock. > > Dominik Dingel (2): > mm: bring in additional flag for fixup_user_fault to signal unlock > s390/mm: enable fixup_user_fault retrying > > arch/s390/mm/pgtable.c | 31 ++++++++++++++++++++++++++++--- > include/linux/mm.h | 5 +++-- > kernel/futex.c | 2 +- > mm/gup.c | 30 +++++++++++++++++++++++++----- > 4 files changed, 57 insertions(+), 11 deletions(-) > > -- > 2.3.0 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>