On 07/07/2023 22:55, Axel Rasmussen wrote: > The test is pretty basic, and exercises UFFDIO_POISON straightforwardly. > We register a region with userfaultfd, in missing fault mode. For each > fault, we either UFFDIO_COPY a zeroed page (odd pages) or UFFDIO_POISON > (even pages). We do this mix to test "something like a real use case", > where guest memory would be some mix of poisoned and non-poisoned pages. > > We read each page in the region, and assert that the odd pages are > zeroed as expected, and the even pages yield a SIGBUS as expected. > > Why UFFDIO_COPY instead of UFFDIO_ZEROPAGE? Because hugetlb doesn't > support UFFDIO_ZEROPAGE, and we don't want to have special case code. > > Acked-by: Peter Xu <peterx@xxxxxxxxxx> > Signed-off-by: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> Hi, FYI, when running this test on arm64 it provokes a kernel panic. I've posted a fix along with a detailed explanation at [1]. [1] https://lore.kernel.org/linux-arm-kernel/20230921162007.1630149-1-ryan.roberts@xxxxxxx/ Thanks, Ryan
