On 01/10/2018 01:22 AM, Boris Ostrovsky wrote:
On 01/09/2018 07:10 AM, Ross Lagerwall wrote:
When cleaning up after a partially successful gntdev_mmap(), unmap the
successfully mapped grant pages otherwise Xen will kill the domain if
in debug mode (Attempt to implicitly unmap a granted PTE) or Linux will
kill the process and emit "BUG: Bad page map in process" if Xen is in
release mode.
This is only needed when use_ptemod is true because gntdev_put_map()
will unmap grant pages itself when use_ptemod is false.
Signed-off-by: Ross Lagerwall <[email protected]>
Reviewed-by: Boris Ostrovsky <[email protected]>
although I wonder whether it may be possible to have gntdev_put_map()
figure whether to unmap the pages if use_ptemod is set.
It was a while since I wrote this patch, but IIRC when use_ptemod is
set, successfully mmapped pages are unmapped via the mmu_notifier
release callback. So doing it in gntdev_put_map() isn't possible without
further changes.
--
Ross Lagerwall
