| Message ID | 20201019101230.29860-1-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915: Force VT'd workarounds when running as a guest OS | expand |
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 1a5729932c81..02a3dac412d8 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -33,6 +33,8 @@ #include <uapi/drm/i915_drm.h> #include <uapi/drm/drm_fourcc.h> +#include <asm/hypervisor.h> + #include <linux/io-mapping.h> #include <linux/i2c.h> #include <linux/i2c-algo-bit.h> @@ -1760,6 +1762,13 @@ static inline bool intel_vtd_active(void) if (intel_iommu_gfx_mapped) return true; #endif + +#ifdef CONFIG_HYPERVISOR_GUEST + /* Running as a guest, we assume the host is enforcing VT'd */ + if (x86_hyper_type != X86_HYPER_NATIVE) + return true; +#endif + return false; }
If i915.ko is being used as a passthrough device, it does not know if the host is using intel_iommu. Mixing the iommu and gfx causing a few issues (such as scanout overfetch) which we need to workaround inside the driver, so if we detect we are running under a hypervisor, also assume the device access is being virtualised. Reported-by: Stefan Fritsch <sf@sfritsch.de> Suggested-by: Stefan Fritsch <sf@sfritsch.de> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Stefan Fritsch <sf@sfritsch.de> Cc: stable@vger.kernel.org --- drivers/gpu/drm/i915/i915_drv.h | 9 +++++++++ 1 file changed, 9 insertions(+)