On 20-06-16 15:54, Keith Busch wrote: > On Mon, Jun 20, 2016 at 11:21:09AM -0700, Jethro Beekman wrote: >> On 20-06-16 08:26, Keith Busch wrote: >> >> Would this just be a matter of setting req->retries and checking for it in >> nvme_req_needs_retry? How does one keep track of the number of tries so far? > > I just sent a patch out earlier today to use req->retries to track the > retry count, and nvme module parameter to set the max retries. I think > that would fix the long delays you're seeing, assuming the patch is okay.
Your patch "nvme: Limit command retries" works for me and obviates the need for this patch. >> You're right, I assumed that admin commands can't have namespace ids, but >> looking at the spec, that's not the case. Turns out there's a problem with >> the >> driver then: nvme_ioctl never includes the ns for NVME_IOCTL_ADMIN_CMD. > > The NVME_IOCTL_ADMIN_CMD already takes any namespace identifier the user > put in that field. I see, the ns argument is just to specify the queue. I assume userspace is supposed to obtain the ns using NVME_IOCTL_ID? This seems broken, if I have an open block device handle I can send commands to any nvme namespace as well as the controller? I think on the block devices you should only be able to send commands with your nsid. There was some discussion on the security implications of this about a year ago [1], and it was decided to fix this, but it doesn't look like this was actually merged? [1] http://lists.infradead.org/pipermail/linux-nvme/2015-January/001446.html Jethro