On Jun 16, 2022 / 07:13, Yi Zhang wrote: > On Thu, Jun 16, 2022 at 6:01 AM Chaitanya Kulkarni > <chaitanyak@xxxxxxxxxx> wrote: > > > > On 6/15/22 12:47, Bjorn Helgaas wrote: > > > On Tue, Jun 14, 2022 at 04:00:45AM +0000, Shinichiro Kawasaki wrote: > > >> On Jun 14, 2022 / 02:38, Chaitanya Kulkarni wrote: > > >>> Shinichiro, [snip] > > >>> I think it is worth adding a testcase to blktests to make sure > > >>> these future releases will test this. > > >> > > >> Yeah, this WARN is confusing for us then it would be valuable to > > >> test by blktests not to repeat it. One point I wonder is: which test > > >> group the test case will it fall in? The nvme group could be the > > >> group to add, probably. > > >> > > > > since this issue been discovered with nvme rescan and revmoe, > > it should be added to the nvme category. > > We already have nvme/032 which tests nvme rescan/reset/remove and the > issue was reported by running this one, do we still need one more? That is a point. Current nvme/032 checks nvme pci adapter rescan/reset/remove during I/O to catch problems in nvme driver and block layer, but actually it can catch the problem in pci sub-system also. I think Chaitanya's motivation for the new test case is to distinguish those two. If we have the new test case, its code will be similar and duplicated as nvme/032 code. To avoid such duplication, it would be good to improve nvme/032 to have two steps. The 1st step checks that nvme pci adapter rescan/reset/remove without I/O causes no kernel WARN (or any other unexpected kernel messages). Any issue found in this step is reported as a pci sub-system issue. The 2nd step checks nvme pci adapter rescan/reset/remove during I/O, as the current nvme/032 does. With this, we don't need the new test case, but still we can distinguish the problems in nvme/block sub-system and pci sub-system. > > >> Another point I wonder is other kernel test suite than blktests. > > >> Don't we have more appropriate test suite to check PCI device > > >> rescan/remove race ? Such a test sounds more like a PCI bus > > >> sub-system test than block/storage test. > > > > I don't think so we could have caught it long time back, > > but we clearly did not. I see, then it looks that blktests is the test suite to test it. -- Shin'ichiro Kawasaki