From b24881e0b0b69155b092c525b7fded258d78a46d Mon Sep 17 00:00:00 2001 From: Xiong Zhang Date: Mon, 26 Feb 2018 10:40:18 +0800 Subject: [PATCH] drm/i915/gvt: Add runtime_pm_get/put into gvt_switch_mmio If user continuously create vgpu, boot guest, shoutdown guest and destroy vgpu from remote, the following calltrace exists in dmesg sometimes: [ 6412.954721] RPM wakelock ref not held during HW access [ 6412.954795] WARNING: CPU: 7 PID: 11941 at linux/drivers/gpu/drm/i915/intel_drv.h:1800 intel_uncore_forcewake_get.part.7+0x96/0xa0 [i915] [ 6412.954915] Call Trace: [ 6412.954951] intel_uncore_forcewake_get+0x18/0x20 [i915] [ 6412.954989] intel_gvt_switch_mmio+0x8e/0x770 [i915] [ 6412.954996] ? __slab_free+0x14d/0x2c0 [ 6412.955001] ? __slab_free+0x14d/0x2c0 [ 6412.955006] ? __slab_free+0x14d/0x2c0 [ 6412.955041] intel_vgpu_stop_schedule+0x92/0xd0 [i915] [ 6412.955073] intel_gvt_deactivate_vgpu+0x48/0x60 [i915] [ 6412.955078] __intel_vgpu_release+0x55/0x260 [kvmgt] when this happens, gvt_switch_mmio is called at vgpu destroy, host i915 is idle and doesn't hold RPM wakelock, igd is in powersave mode, but gvt_switch_mmio require igd power on to access register, so intel_runtime_pm_get should be added to make sure igd power on before gvt_switch_mmio. v2: Move runtime_pm_get/put into gvt_switch_mmio.(Zhenyu) Signed-off-by: Xiong Zhang Signed-off-by: Zhi Wang --- drivers/gpu/drm/i915/gvt/mmio_context.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/gvt/mmio_context.c b/drivers/gpu/drm/i915/gvt/mmio_context.c index 256f1bb5..152df3d 100644 --- a/drivers/gpu/drm/i915/gvt/mmio_context.c +++ b/drivers/gpu/drm/i915/gvt/mmio_context.c @@ -394,9 +394,11 @@ void intel_gvt_switch_mmio(struct intel_vgpu *pre, * performace for batch mmio read/write, so we need * handle forcewake mannually. */ + intel_runtime_pm_get(dev_priv); intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL); switch_mmio(pre, next, ring_id); intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL); + intel_runtime_pm_put(dev_priv); } /** -- 2.7.4