On Wed, Feb 15, 2023 at 10:03:27AM +0000, Jonathan Cameron wrote:
On Tue, 14 Feb 2023 16:54:02 -0500 Gregory Price gregory.price@memverge.com wrote:
Just clarifying one thing: Even with the patch, KVM blows up. Disabling KVM fixes this entirely. I haven't tested without KVM but with the patch, i will do that now.
yup. The patch only fixes TCG so that's expected behavior.
Fingers crossed on this 'working'.
I'm open to suggestions on how to work around the problem with KVM or indeed allow TCG to cache the instructions (right not it has to fetch and emulate each instruction on it's own).
I can envision how we might do it for KVM with userspace page fault handling used to get a fault up to QEMU which can then stitch in a cache of the underlying memory as a stage 2 translation to the page (a little bit like how post migration copy works) though I've not prototyped anything...
Just following up. With the patch applied and KVM turned off, no crash. I've been working with this for a while.
We should move the instruction alignment issue into a separate discussion thread.