On Tue, Dec 15, 2020 at 08:55:57PM +0100, javier@xxxxxxxxxxx wrote: > From: Javier González <javier.gonz@xxxxxxxxxxx> > > Create a char device per NVMe namespace. This char device is always > initialized, independently of whether the features implemented by the > device are supported by the kernel. User-space can therefore always > issue IOCTLs to the NVMe driver using the char device. > > The char device is presented as /dev/generic-nvmeXcYnZ. This naming > scheme follows the convention of the hidden device (nvmeXcYnZ). Support > for multipath will follow. > > Christoph, Keith: Is this going in the right direction? I think this is looking okay, though I'm getting some weird errors and warnings during boot. The first one looks like the following (I will look into it too, but I wanted to get a reply out sooner). [ 4.734143] sysfs: cannot create duplicate filename '/dev/char/242:1' [ 4.736359] CPU: 4 PID: 7 Comm: kworker/u16:0 Not tainted 5.10.0+ #172 [ 4.740836] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 4.744228] Workqueue: nvme-wq nvme_scan_work [nvme_core] [ 4.745558] Call Trace: [ 4.746122] dump_stack+0x6d/0x88 [ 4.746834] sysfs_warn_dup.cold+0x17/0x24 [ 4.747656] sysfs_do_create_link_sd.isra.0+0xb0/0xc0 [ 4.747659] device_add+0x604/0x7b0 [ 4.749298] cdev_device_add+0x46/0x70 [ 4.753241] ? cdev_init+0x51/0x60 [ 4.753246] nvme_alloc_ns+0x670/0x8a0 [nvme_core] [ 4.753249] ? _cond_resched+0x15/0x30 [ 4.753253] nvme_validate_or_alloc_ns+0x99/0x190 [nvme_core] [ 4.753258] nvme_scan_work+0x152/0x290 [nvme_core] [ 4.753261] process_one_work+0x1ac/0x330 [ 4.753262] worker_thread+0x50/0x3a0 [ 4.753264] ? process_one_work+0x330/0x330 [ 4.753265] kthread+0xfb/0x130 [ 4.753266] ? kthread_park+0x90/0x90 [ 4.753269] ret_from_fork+0x1f/0x30 [ 4.753272] CPU: 5 PID: 88 Comm: kworker/u16:1 Not tainted 5.10.0+ #172 > Keith: Regarding nvme-cli support, what do you think about reporting the > char device as existing block devices? If this is OK with you, I will > submit patches for the filters. I'm not sure I understand what you mean about reporting these as "existing block devices". Are you talking about what's shown in the 'nvme list' output?
