On Wed, Jul 21, 2021 at 08:37:21AM +0100, Fuad Tabba wrote: > On Tue, Jul 20, 2021 at 3:53 PM Andrew Jones <drjones@xxxxxxxxxx> wrote: > > > > On Mon, Jul 19, 2021 at 05:03:37PM +0100, Fuad Tabba wrote: > > > On deactivating traps, restore the value of mdcr_el2 from the > > > newly created and preserved host value vcpu context, rather than > > > directly reading the hardware register. > > > > > > Up until and including this patch the two values are the same, > > > i.e., the hardware register and the vcpu one. A future patch will > > > be changing the value of mdcr_el2 on activating traps, and this > > > ensures that its value will be restored. > > > > > > No functional change intended. > > > > I'm probably missing something, but I can't convince myself that the host > > will end up with the same mdcr_el2 value after deactivating traps after > > this patch as before. We clearly now restore whatever we had when > > activating traps (presumably whatever we configured at init_el2_state > > time), but is that equivalent to what we had before with the masking and > > ORing that this patch drops? > > You're right. I thought that these were actually being initialized to > the same values, but having a closer look at the code the mdcr values > are not the same as pre-patch. I will fix this. Can you elaborate on the issue here, please? I was just looking at this but aren't you now relying on __init_el2_debug to configure this, which should be fine? Will _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
