b24881e0b0
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>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.