On Thu, 2014-08-07 at 12:11 +0300, Boaz Harrosh wrote: > On 08/07/2014 02:06 AM, Ross Zwisler wrote: > > Also, it looks like you can still create a new device with this patch, but you > > can't create partitions on that device. Not sure if this is just what you get > > when you dynamically create a device on the fly, or if it's a symptom of > > something larger. > > > > What? I just tried again this all works fine for me, here with fdisk. > $ modprobe brd # will create ram0-7 > $ mknod /dev/ram8 b 1 8 > $ fdisk /dev/ram8 > g, n, , , +2M, n, , , , , w > > I create 2 partitions 2M each and press w and it is all there. > > What numbers did you use ? rd_nr, max_part, and the mknod numbers. Here it > just works fine. What did you try? Ah - it turns out the issue was that I wasn't following the naming scheme "ramX" where X is your new device name. Here's the sequence: # mknod /dev/ram_new b 1 6 # fdisk /dev/ram_new < create some partitions> This ends up creating a "ram_new" and a "ram6", which have the same major/minor. The partitions do show up, but they live under ram6: brw-rw---- 1 root disk 1, 6 Aug 7 12:36 ram6 brw-rw---- 1 root disk 259, 0 Aug 7 12:36 ram6p1 brw-rw---- 1 root disk 259, 1 Aug 7 12:36 ram6p2 brw-r--r-- 1 root root 1, 6 Aug 7 12:36 ram_new You can run fdisk -l, etc, on ram_new, and it'll show you the partitions, they just won't be surfaced in /dev. ram6 and ram_new seem to be alaises: # fdisk -l /dev/ram_new Disk /dev/ram_new: 8589 MB, 8589934592 bytes 64 heads, 32 sectors/track, 8192 cylinders Units = cylinders of 2048 * 512 = 1048576 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2812942c Device Boot Start End Blocks Id System /dev/ram_new1 1 2049 2098160 83 Linux /dev/ram_new2 2050 8192 6290432 83 Linux This device aliasing happened with the old BRD code as well, so this isn't new behavior. - Ross -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
