From b24881e0b0b69155b092c525b7fded258d78a46d Mon Sep 17 00:00:00 2001
From: Xiong Zhang <xiong.y.zhang@intel.com>
Date: Mon, 26 Feb 2018 10:40:18 +0800
Subject: [PATCH] drm/i915/gvt: Add runtime_pm_get/put into gvt_switch_mmio
Git-commit: b24881e0b0b69155b092c525b7fded258d78a46d
Patch-mainline: v4.16-rc6
References: FATE#322643 bsc#1055900
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 <xiong.y.zhang@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/gvt/mmio_context.c | 2 ++
1 file changed, 2 insertions(+)
--- 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_
* 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);
}
/**