From 0a1b60d76b0abcc2a0de4eb96d5dd379cd855f30 Mon Sep 17 00:00:00 2001 From: Zhenyu Wang Date: Fri, 31 Aug 2018 10:58:52 +0800 Subject: [PATCH 1/2] drm/i915/gvt: Fix life cycle reference on KVM mm Handle guest mm access life cycle properly with mmget()/mmput(). As noted by Linus, use_mm() depends on valid live page table but KVM's mmgrab() doesn't guarantee that. As vGPU usage depends on guest VM life cycle, need to make sure to use mmget()/mmput() to guarantee VM address access. v3: fix build v2: v1 caused a weird dependence issue which failed for vfio device release, which result invalid mdev vgpu and kvm state without proper release taken. This trys to put right reference around VM address space access instead. Cc: Linus Torvalds Cc: Paolo Bonzini Cc: Zhi Wang Reviewed-by: Zhi Wang Signed-off-by: Zhenyu Wang --- drivers/gpu/drm/i915/gvt/kvmgt.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index a45f46d8537f1..c7afee37b2b8c 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include #include @@ -1792,16 +1793,21 @@ static int kvmgt_rw_gpa(unsigned long handle, unsigned long gpa, info = (struct kvmgt_guest_info *)handle; kvm = info->kvm; - if (kthread) + if (kthread) { + if (!mmget_not_zero(kvm->mm)) + return -EFAULT; use_mm(kvm->mm); + } idx = srcu_read_lock(&kvm->srcu); ret = write ? kvm_write_guest(kvm, gpa, buf, len) : kvm_read_guest(kvm, gpa, buf, len); srcu_read_unlock(&kvm->srcu, idx); - if (kthread) + if (kthread) { unuse_mm(kvm->mm); + mmput(kvm->mm); + } return ret; } From 792fab2c0d45758ad3d187bd252570d2bb627fa9 Mon Sep 17 00:00:00 2001 From: Weinan Li Date: Tue, 4 Sep 2018 14:13:43 +0800 Subject: [PATCH 2/2] drm/i915/gvt: Fix the incorrect length of child_device_config issue GVT-g emualte the opregion for guest with bdb version as '186' which child_device_config length should be '33'. v2: split into 2 patch. 1st for issue fix, 2nd for code clean up.(Zhenyu) v3: add fixes tag.(Zhenyu) Fixes: 4023f301d28f ("drm/i915/gvt: opregion virtualization for win") CC: Xiaolin Zhang Reviewed-by: Xiaolin Zhang Signed-off-by: Weinan Li Signed-off-by: Zhenyu Wang --- drivers/gpu/drm/i915/gvt/opregion.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/i915/gvt/opregion.c b/drivers/gpu/drm/i915/gvt/opregion.c index fa75a2eead907..b0d3a43ccd033 100644 --- a/drivers/gpu/drm/i915/gvt/opregion.c +++ b/drivers/gpu/drm/i915/gvt/opregion.c @@ -42,8 +42,6 @@ #define DEVICE_TYPE_EFP3 0x20 #define DEVICE_TYPE_EFP4 0x10 -#define DEV_SIZE 38 - struct opregion_header { u8 signature[16]; u32 size; @@ -63,6 +61,10 @@ struct bdb_data_header { u16 size; /* data size */ } __packed; +/* For supporting windows guest with opregion, here hardcode the emulated + * bdb header version as '186', and the corresponding child_device_config + * length should be '33' but not '38'. + */ struct efp_child_device_config { u16 handle; u16 device_type; @@ -109,12 +111,6 @@ struct efp_child_device_config { u8 mipi_bridge_type; /* 171 */ u16 device_class_ext; u8 dvo_function; - u8 dp_usb_type_c:1; /* 195 */ - u8 skip6:7; - u8 dp_usb_type_c_2x_gpio_index; /* 195 */ - u16 dp_usb_type_c_2x_gpio_pin; /* 195 */ - u8 iboost_dp:4; /* 196 */ - u8 iboost_hdmi:4; /* 196 */ } __packed; struct vbt { @@ -155,7 +151,7 @@ static void virt_vbt_generation(struct vbt *v) v->header.bdb_offset = offsetof(struct vbt, bdb_header); strcpy(&v->bdb_header.signature[0], "BIOS_DATA_BLOCK"); - v->bdb_header.version = 186; /* child_dev_size = 38 */ + v->bdb_header.version = 186; /* child_dev_size = 33 */ v->bdb_header.header_size = sizeof(v->bdb_header); v->bdb_header.bdb_size = sizeof(struct vbt) - sizeof(struct vbt_header) @@ -169,11 +165,13 @@ static void virt_vbt_generation(struct vbt *v) /* child device */ num_child = 4; /* each port has one child */ + v->general_definitions.child_dev_size = + sizeof(struct efp_child_device_config); v->general_definitions_header.id = BDB_GENERAL_DEFINITIONS; /* size will include child devices */ v->general_definitions_header.size = - sizeof(struct bdb_general_definitions) + num_child * DEV_SIZE; - v->general_definitions.child_dev_size = DEV_SIZE; + sizeof(struct bdb_general_definitions) + + num_child * v->general_definitions.child_dev_size; /* portA */ v->child0.handle = DEVICE_TYPE_EFP1;