It is 1.3 in buildroot Reproducible: Always Steps to Reproduce: 1.mount 2. mount -t udev udev /dev 3. /etc/init.d/S10udev start 4. mount 5. mount -t udev udev /dev Actual Results: [root@kyou ~]# mount rootfs on / type rootfs (rw) /dev/root on / type ext4 (rw,relatime,data=ordered) devtmpfs on /dev type devtmpfs (rw,relatime,size=489840k,nr_inodes=122460,mode=755) proc on /proc type proc (rw,relatime) devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620) tmpfs on /dev/shm type tmpfs (rw,relatime,mode=777) tmpfs on /tmp type tmpfs (rw,relatime) sysfs on /sys type sysfs (rw,relatime) [root@kyou ~]# mount -t udev udev /dev mount: mounting udev on /dev failed: No such device [root@kyou ~]# /etc/init.d/S10udev start Populating /dev using udev: done [root@kyou ~]# mount rootfs on / type rootfs (rw) /dev/root on / type ext4 (rw,relatime,data=ordered) devtmpfs on /dev type devtmpfs (rw,relatime,size=489840k,nr_inodes=122460,mode=755) proc on /proc type proc (rw,relatime) devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620) tmpfs on /dev/shm type tmpfs (rw,relatime,mode=777) tmpfs on /tmp type tmpfs (rw,relatime) sysfs on /sys type sysfs (rw,relatime) [root@kyou ~]# mount -t udev udev /dev mount: mounting udev on /dev failed: No such device Does eudev need devtmpfs and auto mount it? I have enabled them as without it I can't mount /dev at all. But the udev from systemd seems doesn't need it.
(In reply to ayaka from comment #0) > Does eudev need devtmpfs and auto mount it? Yes. > I have enabled them as without it I can't mount /dev at all. > But the udev from systemd seems doesn't need it. Both sys-fs/udev (bug #463475) and sys-fs/eudev have a pkg_setup() check that warns you when CONFIG_DEVTMPFS is not enabled in your current kernel. sys-kernel/gentoo-sources defaults to having it enabled (bug #455880) *** This bug has been marked as a duplicate of bug 408947 ***
(In reply to Jeroen Roovers from comment #1) > (In reply to ayaka from comment #0) > > Does eudev need devtmpfs and auto mount it? > > Yes. > > > I have enabled them as without it I can't mount /dev at all. > > But the udev from systemd seems doesn't need it. > > Both sys-fs/udev (bug #463475) and sys-fs/eudev have a pkg_setup() check > that warns you when CONFIG_DEVTMPFS is not enabled in your current kernel. > > sys-kernel/gentoo-sources defaults to having it enabled (bug #455880) > > *** This bug has been marked as a duplicate of bug 408947 *** No, I have enabled devtmpfs. The problem is not about devtmpfs, but udev, eudev can't replacee devtmpfs in /dev.
(In reply to ayaka from comment #0) > It is 1.3 in buildroot > > Reproducible: Always > > Steps to Reproduce: > 1.mount > 2. mount -t udev udev /dev Don't do that. > 5. mount -t udev udev /dev Again, wrong command line. > devtmpfs on /dev type devtmpfs > (rw,relatime,size=489840k,nr_inodes=122460,mode=755) Looks good. > [root@kyou ~]# mount -t udev udev /dev > mount: mounting udev on /dev failed: No such device Don't do that. I don't see any problems mentioned in the bug, reclose as INVALID
S(In reply to ayaka from comment #2) > (In reply to Jeroen Roovers from comment #1) > > (In reply to ayaka from comment #0) > > > Does eudev need devtmpfs and auto mount it? > > > > Yes. > > > > > I have enabled them as without it I can't mount /dev at all. > > > But the udev from systemd seems doesn't need it. > > > > Both sys-fs/udev (bug #463475) and sys-fs/eudev have a pkg_setup() check > > that warns you when CONFIG_DEVTMPFS is not enabled in your current kernel. > > > > sys-kernel/gentoo-sources defaults to having it enabled (bug #455880) > > > > *** This bug has been marked as a duplicate of bug 408947 *** > > No, I have enabled devtmpfs. The problem is not about devtmpfs, but udev, > eudev can't replacee devtmpfs in /dev. (In reply to Samuli Suominen from comment #3) > (In reply to ayaka from comment #0) > > It is 1.3 in buildroot > > > Again, wrong command line. [root@kyou ~]# udevadm trigger --type=subsystems --action=add [root@kyou ~]# udevadm trigger --type=devices --action=add [root@kyou ~]# udevadm settle --timeout=60 [root@kyou ~]# mount -n -t devtmpfs -o "exec,nosuid,mode=0755,size=10M" udev /dev mount: mounting udev on /dev failed: Device or resource busy I think this time it is the correct command line And I have tried [root@kyou ~]# echo -e '\000\000\000\000' > /proc/sys/kernel/hotplug [root@kyou ~]# udevadm trigger it doesn't work either. > > Looks good. > no, I think the correct result shall like this udev on /dev type devtmpfs (rw,relatime,size=10240k,nr_inodes=122460,mode=755) but it is devtmpfs on /dev type devtmpfs (rw,relatime,size=10240k,nr_inodes=122460,mode=755) now > > I don't see any problems mentioned in the bug, reclose as INVALID The problem is that udev doesn't take manage of /dev
