Windows 8 Physical Disk UEFI Linux Guest Problem

[maxexcloo]

Hello,
I'm on Windows 8 64 bit and trying to boot a Linux partition on the same physical disk as Windows.
I am using GPT and EFI/UEFI mode and while booting does work my EXT4 partition appears to be read only.
I have tried booting live CDs in the VM and mounting and while the partition appears to be mounted read/write I am unable to edit files, leading me to believe that the issue is with VirtualBox/Windows. I have attempted setting my ext4 volume offline with diskpart to no effect.

VirtualBox Logs (too large to paste here, haven't been a member long enough to post URLs :\)
pastebin. com/raw.php?i=fWFCwcCz

Windows DISKPART

Code: Select all

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
* Disk 0    Online          119 GB      0 B        *
  Disk 1    Online          931 GB      0 B        *

DISKPART> list volume

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0     C   Windows 8    NTFS   Partition     64 GB  Healthy    Boot
  Volume 1                             Partition     50 GB  Healthy    Offline
  Volume 2                      NTFS   Partition    300 MB  Healthy    Hidden
  Volume 3                      FAT32  Partition    100 MB  Healthy    System
  Volume 4     D   Data         NTFS   Partition    931 GB  Healthy

Linux dmesg (too large to paste here, haven't been a member long enough to post URLs :\)
pastebin. com/raw.php?i=RrvMQguB

Linux /proc/mounts

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rootfs / rootfs rw 0 0
proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
sys /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0
dev /dev devtmpfs rw,nosuid,relatime,size=1023896k,nr_inodes=255974,mode=755 0 0
run /run tmpfs rw,nosuid,nodev,relatime,mode=755 0 0
/dev/sda5 / ext4 ro,relatime,data=ordered 0 0
securityfs /sys/kernel/security securityfs rw,nosuid,nodev,noexec,relatime 0 0
tmpfs /dev/shm tmpfs rw,nosuid,nodev 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
tmpfs /sys/fs/cgroup tmpfs rw,nosuid,nodev,noexec,mode=755 0 0
cgroup /sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 0 0
pstore /sys/fs/pstore pstore rw,nosuid,nodev,noexec,relatime 0 0
efivarfs /sys/firmware/efi/efivars efivarfs rw,nosuid,nodev,noexec,relatime 0 0
cgroup /sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0
cgroup /sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0
cgroup /sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0
cgroup /sys/fs/cgroup/devices cgroup rw,nosuid,nodev,noexec,relatime,devices 0 0
cgroup /sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0
cgroup /sys/fs/cgroup/net_cls cgroup rw,nosuid,nodev,noexec,relatime,net_cls 0 0
cgroup /sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0
systemd-1 /proc/sys/fs/binfmt_misc autofs rw,relatime,fd=35,pgrp=1,timeout=300,minproto=5,maxproto=5,direct 0 0
debugfs /sys/kernel/debug debugfs rw,relatime 0 0
mqueue /dev/mqueue mqueue rw,relatime 0 0
hugetlbfs /dev/hugepages hugetlbfs rw,relatime 0 0
tmpfs /tmp tmpfs rw 0 0
configfs /sys/kernel/config configfs rw,relatime 0 0
fusectl /sys/fs/fuse/connections fusectl rw,relatime 0 0

Thanks for any assistance!

[noteirak]

Check this post, if you haven't already.

[maxexcloo]

Check this post, if you haven't already.

I can't offline the disk as I'm running Windows off it.

[noteirak]

Then I cannot help further I am afraid. Raw access is an expert feature and shouldn't be tried out on an important disk like the one where your system resides IMHO.
I personally cannot help further on this matter. Maybe others with more experience will be willing.

[mpack]

I doubt this can work. The drive is effectively owned by Windows (everything goes through a Windows low level disk driver), and if the drive is locked because Windows itself is on it, then obviously the driver isn't going to allow anything else to write to the drive. It's possible you can get read only access as an immutable drive, but I prefer to avoid raw disk access entirely.

[maxexcloo]

Oddly enough when using single partition mode in VMWare Workstation the disk does appear to work.
Unfortunately it appears that VirtualBox physical partition mode doesn't support GPT formatted disks (it crashes when I attempt to list partitions).

[mpack]

Yes, last I heard VirtualBox doesn't support GPT partitions, so "list partitions" etc won't work. However that by itself shouldn't prevent raw access to a partition provided the host is able to find that partition, and it allows access. Of course the guest can't boot from a partition image, so you'd need to provide a "virtual MBR" separately.

[maxexcloo]

Yes, last I heard VirtualBox doesn't support GPT partitions, so "list partitions" etc won't work. However that by itself shouldn't prevent raw access to a partition provided the host is able to find that partition, and it allows access. Of course the guest can't boot from a partition image, so you'd need to provide a "virtual MBR" separately.

It looks like I'll just have to use VMware Workstation for now as it seems to work well in that (although it's not open source or free :\)