RT-3.10.6_p3 fails to boot: home.mount mounting timed out
I am trying to build a RT kernel, however it cannot boot because it
cannot mount /home, which is a subvolume of btrfs. This is the entry of it in /etc/fstab:
/dev/sda3 /home btrfs subvol=gentoohome,defaults,compress=lzo,autodefrag 0 2
I copyed my .config from a working mainline 3.10 kernel(which is able to boot) and used "make oldconfig". The resulting config file is almost the same with mainline one: I only changed IO scheduler from BFQ(from gentoo patchset) to deadline, without even enabling CONFIG_PREEMPT_RT. However the RT kernel just cannot boot.
Could someone help me figure it out? I bought a new recording device
and need low latency audio system. Thanks!
The attached file includes .config for RT kernel and the working mainline kernel, and the boot log of one failed boot.
Quoted 6 lines · * Light | 2013-10-26 12:35:54 [+0800]:
I am trying to build a RT kernel, however it cannot boot because it cannot mount /home, which is a subvolume of btrfs. This is the entry of it in
/etc/fstab:
/dev/sda3/home btrfs
subvol=gentoohome,defaults,compress=lzo,autodefrag 0 2
And this is okay it seems :)
Quoted 5 lines
I copyed my .config from a working mainline 3.10 kernel(which is able to boot) and used "make oldconfig". The resulting config file is almost the same with mainline one: I only changed IO scheduler from BFQ(from gentoo patchset) to deadline, without even enabling
CONFIG_PREEMPT_RT. However the RT kernel just cannot boot.
That is interresting. Does vanila v3.10.4 / v3.10.6 work? In your bootlog I see
| Oct 26 11:33:19 Light kernel: 1;39mKernel command line: root=/dev/sda3 rootflags=subvol=gentoo init=/usr/lib/systemd/systemd ro | Oct 26 11:33:19 Light kernel: sda: sda1 sda2 sda3 sda4 | Oct 26 11:33:19 Light kernel: VFS: Mounted root (btrfs filesystem) readonly on device 0:12.
which means the disk there and btrfs was able to mount the root subvolume. However your home subvolume timed out. If there is nothing different with the way you create the kernel (initramfs and such) then I have no clue.
Maybe you could remove /home from fstab and mount it from commandline because this might show you the error here.
Sebastian
Quoted 8 lines · * Sebastian Andrzej Siewior | 2013-11-22 16:13:44 [+0100]:
Quoted 6 lines · * Light | 2013-10-26 12:35:54 [+0800]:
I am trying to build a RT kernel, however it cannot boot because it cannot mount /home, which is a subvolume of btrfs. This is the entry of it in
/etc/fstab:
/dev/sda3/home btrfs
subvol=gentoohome,defaults,compress=lzo,autodefrag 0 2
So I tried this myself. I've setup a FC19 box with btrfs with a root subvolume and a home subvolume. The etc/fstab
|[root@fc19-64 ~]# grep btrfs /etc/fstab |UUID=b5045733-8f7d-48e4-a4ad-a58bf44cb49f / btrfs subvol=root 1 1 |UUID=b5045733-8f7d-48e4-a4ad-a58bf44cb49f /home btrfs subvol=home 1 1
and it booted:
|[root@fc19-64 ~]# uname -a |Linux fc19-64.testing 3.12.8-rt10 #250 SMP PREEMPT RT Fri Jan 24 19:18:38 CET 2014 x86_64 x86_64 x86_64 GNU/Linux |[root@fc19-64 ~]# mount | grep btrfs |/dev/vda2 on / type btrfs (rw,relatime,seclabel,space_cache) |/dev/vda2 on /home type btrfs (rw,relatime,seclabel,space_cache)
except for the different mount opts (compress=lzo,autodefrag) I don't see what is different here.
Sebastian