Commits
Hang Yuan committed 3fd34ac02ae
drm/i915/gvt: fix cleanup sequence in intel_gvt_clean_device Create one vGPU and then unbind IGD device from i915 driver. The following oops will happen. This patch will free vgpu resource first and then gvt resource to remove these oops. BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8 PGD 80000003c9d2c067 P4D 80000003c9d2c067 PUD 3c817c067 P MD 0 Oops: 0002 [#1] SMP PTI RIP: 0010:down_write+0x1b/0x40 Call Trace: debugfs_remove_recursive+0x46/0x1a0 intel_gvt_debugfs_remove_vgpu+0x15/0x30 [i915] intel_gvt_destroy_vgpu+0x2d/0xf0 [i915] intel_vgpu_remove+0x2c/0x30 [kvmgt] mdev_device_remove_ops+0x23/0x50 [mdev] mdev_device_remove+0xdb/0x190 [mdev] mdev_device_remove+0x190/0x190 [mdev] device_for_each_child+0x47/0x90 mdev_unregister_device+0xd5/0x120 [mdev] intel_gvt_clean_device+0x91/0x120 [i915] i915_driver_unload+0x9d/0x120 [i915] i915_pci_remove+0x15/0x20 [i915] pci_device_remove+0x3b/0xc0 device_release_driver_internal+0x157/0x230 unbind_store+0xfc/0x150 kernfs_fop_write+0x10f/0x180 __vfs_write+0x36/0x180 ? common_file_perm+0x41/0x130 ? _cond_resched+0x16/0x40 vfs_write+0xb3/0x1a0 ksys_write+0x52/0xc0 do_syscall_64+0x55/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 BUG: unable to handle kernel NULL pointer dereference at 0 000000000000038 PGD 8000000405bce067 P4D 8000000405bce067 PUD 405bcd067 PM D 0 Oops: 0000 [#1] SMP PTI RIP: 0010:hrtimer_active+0x5/0x40 Call Trace: hrtimer_try_to_cancel+0x25/0x120 ? tbs_sched_clean_vgpu+0x1f/0x50 [i915] hrtimer_cancel+0x15/0x20 intel_gvt_destroy_vgpu+0x4c/0xf0 [i915] intel_vgpu_remove+0x2c/0x30 [kvmgt] mdev_device_remove_ops+0x23/0x50 [mdev] mdev_device_remove+0xdb/0x190 [mdev] ? mdev_device_remove+0x190/0x190 [mdev] device_for_each_child+0x47/0x90 mdev_unregister_device+0xd5/0x120 [mdev] intel_gvt_clean_device+0x89/0x120 [i915] i915_driver_unload+0x9d/0x120 [i915] i915_pci_remove+0x15/0x20 [i915] pci_device_remove+0x3b/0xc0 device_release_driver_internal+0x157/0x230 unbind_store+0xfc/0x150 kernfs_fop_write+0x10f/0x180 __vfs_write+0x36/0x180 ? common_file_perm+0x41/0x130 ? _cond_resched+0x16/0x40 vfs_write+0xb3/0x1a0 ksys_write+0x52/0xc0 do_syscall_64+0x55/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: bc7b0be316ae("drm/i915/gvt: Add basic debugfs infrastructure") Fixes: afe04fbe6c52("drm/i915/gvt: create an idle vGPU") Signed-off-by: Hang Yuan <hang.yuan@linux.intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>