id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
14746	vboxsf Linux guest - File Cache -> Fixed in SVN / 6.0.6	Tom B		"I'm using a Linux guest using a basic Arch Linux install (default kernel, very few packages)

I have a problem with file caching in shared folders. Steps to reproduce:

1) GUEST: mount a shared directory: `mount -t vboxsf share_name /media/share`

2) GUEST: `cat /media/share/existing.file` <-- Works perfectly, displays the contents of the file from HOST

3) HOST: Write new.file into the shared folder:

4) GUEST: `cat /media/share/new.file` <-- Works perfectly, displays contents of newly created file

5) GUEST: `stat /media/share/non-existing.file` <-- As expected displays ""no such file or directory""

6) HOST: Write non-existing.file to the shared directory

7) GUEST: `cat /media/share/non-existing.file` <-- THIS SHOULD WORK NOW AS THE FILE EXISTS BUT INSTEAD SHOWS ""No such file or directory""


When typing `ls /media-share` it shows the  file with ??? for permissions, dates, etc.

If the file is written on the host BEFORE trying to access it on the guest it works as expected. If the guest tries to read the file prior to it's existence, the fact it doesn't exist is cached and the guest cannot see the file after it's been created.

This is the same for both windows and linux hosts with this guest.


Running `echo 3 > /proc/sys/vm/drop_caches` to clear the file cache seems to fix it.

As far as I can tell it's an issue with the file cache. I've tried recompiling the guest's kernel with various options for CONFIG_FSCACHE (arch defaults to =m and the module is not loaded on the guest) 

Is there a fix for this?

4) GUEST: cat new.file"	defect	closed	shared folders	VirtualBox 5.0.6	fixed	vboxsf shared file cache		Linux	all