id summary reporter owner description type status component version resolution keywords cc guest host 8664 vboxsf causing kernel panic with mounted loopback file system after restore from suspend Greg McLearn "My CentOS 5.5 guest O/S uses a read/write NTFS shared folder from my Windows XP Pro SP3 host operating system drive. This shared folder is automatically mounted on boot via /etc/fstab to /mnt/host. Within that shared folder is a 100MB file that functions as a loopback filesystem which was created like this: {{{ dd if=/dev/zero of=/mnt/host/my-loopback-fs.img bs=1M count=100 && mke2fs -F -j /mnt/host/my-loopback-fs.img }}} It can be mounted like: {{{ mount /mnt/host/my-loopback-fs.img -o loop /mnt/lo-fs }}} Once mounted, I close the VM and save the state. I then bring the VM back to life. A kernel panic usually sets in seconds after the VM is reloaded. Sometimes it takes 2 minutes, sometimes it is immediate. Odd things appear with the mounted loopback filesystem if I try to use it such as I/O errors. I've managed to unmount it and remount it before the kernel panic sets in, but I cannot seem to get around the fact that it will eventually occur. Here's uname -a: {{{ Linux ffm-023631-vm1.example.tld 2.6.18-194.32.1.el5 #1 SMP Wed Jan 5 17:53:09 EST 2011 i686 i686 i386 GNU/Linux }}} I've attached the kernel panic screen and a compiled version of vboxsf.ko." defect new shared folders VirtualBox 4.0.4 panic vboxsf loopback other other