Re: [PATCH v5 for-next 2/2] RDMA/hns: Disassociate mmap pages for all uctx when HW is being reset

[Jason Gunthorpe]

On Fri, Sep 20, 2024 at 05:18:14PM +0800, Junxian Huang wrote:

> >> diff --git a/drivers/infiniband/hw/hns/hns_roce_main.c b/drivers/infiniband/hw/hns/hns_roce_main.c
> >> index 4cb0af733587..49315f39361d 100644
> >> --- a/drivers/infiniband/hw/hns/hns_roce_main.c
> >> +++ b/drivers/infiniband/hw/hns/hns_roce_main.c
> >> @@ -466,6 +466,11 @@ static int hns_roce_mmap(struct ib_ucontext *uctx, struct vm_area_struct *vma)
> >>  	pgprot_t prot;
> >>  	int ret;
> >>  
> >> +	if (hr_dev->dis_db) {
> > 
> > How do you clear dis_db after calling to hns_roce_hw_v2_reset_notify_down()? Does it have any locking protection?
> > 
> 
> Sorry for the late response, I just came back from vacation.
> 
> After calling hns_roce_hw_v2_reset_notify_down(), we will call ib_unregister_device()
> and destory all HW resources eventually, so there is no need to clear dis_db.

Why can't you do the unregister device sooner then and avoid all this
special stuff?

I assumed you'd bring the same device back after completing the reset??

Jason