On 02/23/2017 08:23 PM, Herongguang (Stephen) wrote:

On 2017/2/22 22:43, Paolo Bonzini wrote:

quoted

Hopefully Gaohuai and Rongguang can help with this too.

Paolo

.

Yes, we are looking into and testing this.

I think this can result in any memory corruption, if VM1 writes its
PML buffer into VM2’s VMCS (since sched_in/sched_out notifier of VM1
is not registered yet), then VM1 is destroyed (hence its PML buffer
is freed back to kernel), after that, VM2 starts migration, so CPU
logs VM2’s dirty GFNS into a freed memory, results in any memory corruption.

As its severity, this commit
(http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4e59516a12a6ef6dcb660cb3a3f70c64bd60cfec)

is eligible to back port to kernel stable.

Are we expecting that fix to resolve the original issue, or is it a separate 
issue that needs fixing in stable?

Chris