When vmalloc_user is used to create memory that is supposed to be mmap'd to user space, it is necessary for the mmap cookie (eg the offset) to be aligned to SHMLBA. This creates a situation where all virtual mappings of the same physical page share the same virtual cache index and guarantees VIPT coherence. Otherwise the cache is non-coherent and the kernel will not see writes by userspace when reading the shared page (or vice-versa). Reported-by: Josh Beavers <josh.beavers@xxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/sw/rdmavt/mmap.c | 4 ++-- drivers/infiniband/sw/rxe/rxe_mmap.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) The psm cdevs are still broken. Josh confirmed the patch does what it is supposed to, but it doesn't fix VIVT caches. It is depressing the exact same lines are copied between rxe and rdmavt. diff --git a/drivers/infiniband/sw/rdmavt/mmap.c b/drivers/infiniband/sw/rdmavt/mmap.c index e202b8142759f5..6b712eecbd37d9 100644 --- a/drivers/infiniband/sw/rdmavt/mmap.c +++ b/drivers/infiniband/sw/rdmavt/mmap.c @@ -170,9 +170,9 @@ struct rvt_mmap_info *rvt_create_mmap_info(struct rvt_dev_info *rdi, spin_lock_irq(&rdi->mmap_offset_lock); if (rdi->mmap_offset == 0) - rdi->mmap_offset = PAGE_SIZE; + rdi->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA); ip->offset = rdi->mmap_offset; - rdi->mmap_offset += size; + rdi->mmap_offset += ALIGN(size, SHMLBA); spin_unlock_irq(&rdi->mmap_offset_lock); INIT_LIST_HEAD(&ip->pending_mmaps); diff --git a/drivers/infiniband/sw/rxe/rxe_mmap.c b/drivers/infiniband/sw/rxe/rxe_mmap.c index c572a4c09359c9..bd812e00988ed3 100644 --- a/drivers/infiniband/sw/rxe/rxe_mmap.c +++ b/drivers/infiniband/sw/rxe/rxe_mmap.c @@ -156,10 +156,10 @@ struct rxe_mmap_info *rxe_create_mmap_info(struct rxe_dev *rxe, spin_lock_bh(&rxe->mmap_offset_lock); if (rxe->mmap_offset == 0) - rxe->mmap_offset = PAGE_SIZE; + rxe->mmap_offset = ALIGN(PAGE_SIZE, SHMLBA); ip->info.offset = rxe->mmap_offset; - rxe->mmap_offset += size; + rxe->mmap_offset += ALIGN(size, SHMLBA); spin_unlock_bh(&rxe->mmap_offset_lock); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
