On Mon, Aug 30, 2021 at 05:42:32PM +0800, Li Zhijian wrote: > Previously, we noticed the one rpma example was failed[1] since 36f30e486d, > where it will use ODP feature to do RDMA WRITE between fsdax files. > > After digging into the code, we found hmm_vma_handle_pte() will still > return EFAULT even though all the its requesting flags has been > fulfilled. That's because a DAX page will be marked as > (_PAGE_SPECIAL | PAGE_DEVMAP) by pte_mkdevmap(). > > [1]: https://github.com/pmem/rpma/issues/1142 > > CC: stable@xxxxxxxxxxxxxxx > Fixes: 405506274922 ("mm/hmm: add missing call to hmm_pte_need_fault in HMM_PFN_SPECIAL handling") > Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxxxxx> > > --- > V3: adjust the checking order > --- > mm/hmm.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Andrew, can you grab this please? Thanks, Jason
