On Thu, Aug 15, 2019 at 08:52:56PM +0000, Yang, Philip wrote:
hmm_range_fault may return NULL pages because some of pfns are equal to HMM_PFN_NONE. This happens randomly under memory pressure. The reason is for swapped out page pte path, hmm_vma_handle_pte doesn't update fault variable from cpu_flags, so it failed to call hmm_vam_do_fault to swap the page in.
The fix is to call hmm_pte_need_fault to update fault variable.
Change-Id: I2e8611485563d11d938881c18b7935fa1e7c91ee
I'll fix it for you but please be careful not to send Change-id's to the public lists.
Also what is the Fixes line for this?
Signed-off-by: Philip Yang Philip.Yang@amd.com mm/hmm.c | 3 +++ 1 file changed, 3 insertions(+)
Ralph has also been looking at this area also so I'll give him a bit to chime in, otherwise with Jerome's review this looks OK to go to linux-next
Thanks, Jason