On Mon, Mar 08, 2021 at 10:54:22PM -0800, Dan Williams wrote: > Previous kernels allowed the BLKROSET to override the disk's read-only > status. With that situation fixed the pmem driver needs to rely on > revalidate_disk() to clear the disk read-only status after the host > region has been marked read-write. > > Recall that when libnvdimm determines that the persistent memory has > lost persistence (for example lack of energy to flush from DRAM to FLASH > on an NVDIMM-N device) it marks the region read-only, but that state can > be overridden by the user via: > > echo 0 > /sys/bus/nd/devices/regionX/read_only > > ...to date there is no notification that the region has restored > persistence, so the user override is the only recovery. I've just resent my series to kill of ->revalidate_disk for good, so this obvious makes me a little unhappy. Given that ->revalidate_disk only ends up beeing called from the same path that ->open is called, why can't you just hook this up from the open method? Also any reason the sysfs attribute can't just directly propagate the information to the disk?
