Ping: [PATCH] radeon: avoid boot hang in Xen Dom0

[Jan Beulich]

>>> On 13.09.16 at 17:54,  wrote:
> While a hard hang in atom_asic_init() likely points at a deeper problem
> in the driver, restore the capability to boot a Xen Dom0 by simply
> avoiding the call there: Other than for Xen DomU, Dom0 owning a device
> does not really mean is has got passed through to it.
> 
> In case it is of interest for further investigation, lspci for the
> offending device says:
> 
> ATI Technologies Inc RS480 [Radeon Xpress 200G Series] [1002:5954]
> 
> Fixes: 05082b8bbd "drm/radeon: fix asic initialization for virtualized environments"

I may have overlooked a different fix dealing with the problem; if
so, I'd appreciate that fix being pointed out.

Thanks, Jan

> Signed-off-by: Jan Beulich <jbeulich at suse.com>
> ---
>  drivers/gpu/drm/radeon/radeon_device.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> --- 4.8-rc6/drivers/gpu/drm/radeon/radeon_device.c
> +++ 4.8-rc6-radeon-Xen-boot/drivers/gpu/drm/radeon/radeon_device.c
> @@ -34,6 +34,7 @@
>  #include <linux/vgaarb.h>
>  #include <linux/vga_switcheroo.h>
>  #include <linux/efi.h>
> +#include <xen/xen.h>
>  #include "radeon_reg.h"
>  #include "radeon.h"
>  #include "atom.h"
> @@ -642,7 +643,7 @@ void radeon_gtt_location(struct radeon_d
>  static bool radeon_device_is_virtual(void)
>  {
>  #ifdef CONFIG_X86
> -	return boot_cpu_has(X86_FEATURE_HYPERVISOR);
> +	return boot_cpu_has(X86_FEATURE_HYPERVISOR) && !xen_initial_domain();
>  #else
>  	return false;
>  #endif
> 
> 
>