Similar to the warning in the mmu notifer, warning if an hmm mirror callback gets it's blocking vs. nonblocking handling wrong, or if it fails with anything else than -EAGAIN. Cc: Jason Gunthorpe <jgg@xxxxxxxx> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Balbir Singh <bsingharora@xxxxxxxxx> Cc: Ira Weiny <ira.weiny@xxxxxxxxx> Cc: Souptick Joarder <jrdr.linux@xxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> --- mm/hmm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/hmm.c b/mm/hmm.c index 16b6731a34db..52ac59384268 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -205,6 +205,9 @@ static int hmm_invalidate_range_start(struct mmu_notifier *mn, ret = -EAGAIN; break; } + WARN(ret, "%pS callback failed with %d in %sblockable context\n", + mirror->ops->sync_cpu_device_pagetables, ret, + update.blockable ? "" : "non-"); } up_read(&hmm->mirrors_sem); -- 2.22.0
