On Mon, Apr 11, 2022 at 7:41 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > And that is easily fixed by using a lower major for the block dynamic > dev_t. In theory userspace should be able to copy with any major for > it, but I fear something might break so we could make it configurable. We actually have a ton of major numbers free, although it's not obvious because of the whole "they are used by character devices, not block devices" issue. Ie 4-6, 12, 14, 19 are all free, afaik. But yeah, somebody might have a static /dev for some odd embedded case, I guess. That said, it really does look like we just return -EOVERFLOW much too eagerly, for stupid and bad reasons. Considering that BLOCK_EXT_MAJOR has been 259 since 2008, and this is the first time anybody has hit this, I don't think there's much reason to change that major number when the whole error case seems to have been largely a mistake to begin with. Linus