On Wed, Aug 16, 2017 at 12:10:53PM +0100, Marc Zyngier wrote:

On 16/08/17 11:54, Dave Martin wrote:

quoted

On Tue, Aug 15, 2017 at 05:37:55PM +0100, Marc Zyngier wrote:

quoted

On 09/08/17 13:05, Dave Martin wrote:

[...]

quoted

quoted

quoted

+	if (id == SYS_ID_AA64PFR0_EL1) {
+		static bool printed;
+
+		if ((val & (0xfUL << ID_AA64PFR0_SVE_SHIFT)) && !printed) {
+			kvm_info("SVE unsupported for guests, suppressing\n");
+			printed = true;
+		}

Ideally, this should be a vcpu_unimpl_once(). But:
- it doesn't exist
- vcpu_unimpl looks hopelessly x86 specific

Yeah, I looked for an appropriate function and didn't find one ... and
writing one just for this seemed overkill.

quoted

How about turning it into a pr_err_once() instead?

Can do, though should it be an err?

No error has occurred here, rather I want people who discover that their
guest mysteriously doesn't see SVE gets a clue about why.

An "err" is a good way to make it appear on the console. If you want to
make it noticed, that's the way.

OK, I was concerned that overuse of err might be frowned upon.

If this is the preferred way to signal such things, I'm happy to that.

Cheers
---Dave