# kernel 3.7.1 menuconfig missing option large block devices?

## duby2291

"Support for large (2TB+) block devices and files" seems to be missing in this kernel version... Am I just missing something obvious? Without that option I cant get ext4 to mount r/w... so I'm kinda stuck....

Its supposed to be available under the "Enable the block layer" meny in menuconfig, but it isnt there.

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## aCOSwt

 *duby2291 wrote:*   

> Its supposed to be available under the "Enable the block layer" meny in menuconfig, but it isnt there.

 

It depends if you build a 64 bit kernel or not : 

```
Depends on: BLOCK [=y] && !64BIT [=y]
```

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## duby2291

ok.... hmmm well then if that option isnt required for 64bit, then I have no idea why my / partition is mounting ro

I cant even get to the kernel log, because its mounting ro it isnt writing them to disk.......

EDIT: This is the exact error message I get from dmesg

```
 EXT4-fs (sdd3): mounted filesystem with ordered data mode

VFS: Mounted root (ext4 filesystem) readonly on device
```

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## duby2291

here is some info if it helps at all....

/dev/sdd1 /boot ext2 defaults 1 2

/dev/sdd3 / ext4 defaults 0 1

/dev/sdd2 none swap sw 0 0

default 0

timeout 0

title Gentoo Linux

root (hd0,0)

kernel /boot/vmlinuz root=/dev/sdd3 rootfstype=ext4

Really this should be all thats required to boot. I dont understand why its mounting / ro

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## Jaglover

In case of corrupted filesystem it is mounted ro. I'd try booting from a USB stick or CD and run fsck.

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## duby2291

root@Microknoppix:/mnt# fsck /dev/sdd3

fsck from util-linux 2.20.1

e2fsck 1.42.4 (12-Jun-2012)

/dev/sdd3: clean, 295901/14761984 files, 1964096/59017423 blocks

took less than 3s to finish though, so I dont know how much to trust it......

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## wcg

I think that the implication was that you need CONFIG_BLOCK *and*

CONFIG_64BIT in addition to the option itself. Why the option would

not show up in make menuconfig without make oldconfig complaining

I have no idea.

As for the fsck, try:

```

e2fsk -fp /dev/[root partition]

```

edit:

```

e2fsck -fp /dev/[root partition]

```

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## duby2291

 *Quote:*   

> root@Microknoppix:/mnt# fsck -fp /dev/sdd3
> 
> fsck from util-linux 2.20.1
> 
> /dev/sdd3: 295901/14761984 files (0.1% non-contiguous), 1964096/59017423 blocks
> ...

 

still no errors with fsck.

After doing a google search I confirmed that large block devices isnt needed on 64bit installs because since the cpu is 64bit it already has enough address space that it doesnt need that option.

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## Jaglover

Well, then I'd boot up, remount / rw and go from there.

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## duby2291

 *Jaglover wrote:*   

> Well, then I'd boot up, remount / rw and go from there.

 

I'm afraid it isnt that simple.... due to the fact that / is ro none of the startup scripts work. Simply put I'm better off booting to a livecd and chrooting into the environment... which is what I'm doing But that doesnt solve the problem of why it is mounting ro on bootup. I'm at the point know where I'm considering dumping ext4 in favor of ext3, at least I know that mounts properly. But that requires a re-install and I'm not ready to give up on it just yet. This is gentoo linux after all, there IS a solution. I just have to discover the underlying cause of why it is mounting ro......

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## Jaglover

Right, after you remount rw you should start scripts by hand. That's the part of troubleshooting.

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## duby2291

scripts in the boot runlevel arent capable of being restarted. unfortunately the way gentoo works scripts in the boot runlevel are only able to start at boot.

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## NeddySeagoon

duby2291,

dmesg should still be present even if the filesystem is read only.

I suspect your fs is corrupt and can't be fixed by fsck.

dmesg will tell more.  As you say, investigation is difficult.  I have a case like this on a remote server.

Luckily, I don't use extents or barriers or any ext4 only features so mountings as ext3 works.

Is that an option for you?

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## duby2291

when I created the filesystem I used the command mkfs.ext4, so whatever the default options are is what was used. I'm in the process now of running an emerge -e --buildpkgonly world. Then I'll reinstall using the binaries i'm making. I dont know if that is the best option, but it is all i can think of doing.

EDIT: should I try again with ext4, or should I just use the tried and true ext3? should I use mkfs.ext3 or mke2fs -j?

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