Re: [PATCH v4 18/18] hw/arm/virt: Disable LPA2 for -machine virt-6.2

[Peter Maydell]

On Tue, 1 Mar 2022 at 22:00, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> There is a Linux kernel bug present until v5.12 that prevents
> booting with FEAT_LPA2 enabled.  As a workaround for TCG,
> disable this feature for machine versions prior to 7.0.
>
> Cc: Daniel P. Berrangé <berrange@redhat.com>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  include/hw/arm/virt.h | 1 +
>  hw/arm/virt.c         | 7 +++++++
>  2 files changed, 8 insertions(+)

Is it not possible to implement this in the usual "change
property for older versioned machines" way of adding to
the hw_compat arrays?

diff --git a/hw/core/machine.c b/hw/core/machine.c
index d856485cb4d..dac82a709ba 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -37,7 +37,9 @@
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/virtio-pci.h"

-GlobalProperty hw_compat_6_2[] = {};
+GlobalProperty hw_compat_6_2[] = {
+    { "arm-cpu-max", "lpa2", "false" },
+};
 const size_t hw_compat_6_2_len = G_N_ELEMENTS(hw_compat_6_2);

 GlobalProperty hw_compat_6_1[] = {

thanks
-- PMM