On Fri, May 18, 2018 at 07:57:51AM -0600, Keith Busch wrote: > On Fri, May 18, 2018 at 08:20:05AM +0800, Ming Lei wrote: > > What I think block/011 is helpful is that it can trigger IO timeout > > during reset, which can be triggered in reality too. > > As I mentioned earlier, there is nothing wrong with the spirit of > the test. What's wrong with it is the misguided implemention. > > Do you underestand why it ever passes? The success happens when the > enabling part of the loop happens to coincide with the driver's enabling, > creating the pci_dev->enable_cnt > 1, making subsequent disable parts > of the loop do absolutely nothing; the exact same as the one-liner > (non-serious) patch I sent to defeat the test. > > A better way to induce the timeout is: > > # setpci -s <B:D.f> 4.w=0:6 > > This will halt the device without messing with the kernel structures, > just like how a real device failure would occur. Frankly speaking, I don't care how the test-case is implemented at all. The big problem is that NVMe driver can't handle IO time-out during reset context, and finally either the controller becomes DEAD or reset context hangs forever, and everything can't move on. The issue can be reproduced easier via io-timeout-fail fault injection. So could we please face to the real issue instead of working around test case? Thanks, Ming