On Fri, 3 Feb 2017 16:07:29 +0100 Jan Kara <jack@xxxxxxx> wrote: > Some ->page_mkwrite handlers may return VM_FAULT_RETRY as its return > code (GFS2 or Lustre can definitely do this). However VM_FAULT_RETRY > from ->page_mkwrite is completely unhandled by the mm code and results > in locking and writeably mapping the page which definitely is not what > the caller wanted. Fix Lustre and block_page_mkwrite_ret() used by other > filesystems (notably GFS2) to return VM_FAULT_NOPAGE instead which > results in bailing out from the fault code, the CPU then retries the > access, and we fault again effectively doing what the handler wanted. I'm not getting any sense of the urgency of this fix. The bug *sounds* bad? Which kernel versions need fixing?
