drm/amdgpu: Fix general protection fault in amdgpu_vm_bo_reset_state_machine

After GPU reset with VRAM loss, a general protection fault occurs
during user queue restoration when accessing vm_bo->vm after
spinlock release in amdgpu_vm_bo_reset_state_machine.

The root cause is that vm_bo points to the last entry from the
list_for_each_entry loop, but this becomes invalid after the
spinlock is released. Accessing vm_bo->vm at this point leads
to memory corruption.

Crash log shows:
[  326.981811] Oops: general protection fault, probably for non-canonical address 0x4156415741e58ac8: 0000 [#1] SMP NOPTI
[  326.981820] CPU: 13 UID: 0 PID: 1035 Comm: kworker/13:3 Tainted: G            E       6.16.0+ #25 PREEMPT(voluntary)
[  326.981826] Tainted: [E]=UNSIGNED_MODULE
[  326.981827] Hardware name: Gigabyte Technology Co., Ltd. X870E AORUS PRO ICE/X870E AORUS PRO ICE, BIOS F3i 12/19/2024
[  326.981831] Workqueue: events amdgpu_userq_restore_worker [amdgpu]
[  326.981999] RIP: 0010:amdgpu_vm_assert_locked+0x16/0x70 [amdgpu]
[  326.982094] Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 85 ff 74 45 48 8b 87 80 03 00 00 48 85 c0 74 40 <48> 8b b8 80 01 00 00 48 85 ff 74 3b 8b 05 0c b7 0e f0 85 c0 75 05
[  326.982098] RSP: 0018:ffffaa91c2a6bc20 EFLAGS: 00010206
[  326.982100] RAX: 4156415741e58948 RBX: ffff9e8f013e8330 RCX: 0000000000000000
[  326.982102] RDX: 0000000000000005 RSI: 000000001d254e88 RDI: ffffffffc144814a
[  326.982104] RBP: ffffaa91c2a6bc68 R08: 0000004c21a25674 R09: 0000000000000001
[  326.982106] R10: 0000000000000001 R11: dccaf3f2f82863fc R12: ffff9e8f013e8000
[  326.982108] R13: ffff9e8f013e8000 R14: 0000000000000000 R15: ffff9e8f09980000
[  326.982110] FS:  0000000000000000(0000) GS:ffff9e9e79995000(0000) knlGS:0000000000000000
[  326.982112] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  326.982114] CR2: 000055ed6c9caa80 CR3: 0000000797060000 CR4: 0000000000750ef0
[  326.982116] PKRU: 55555554

Reviewed-by: Christian König <[email protected]>
Signed-off-by: Jesse Zhang <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

Author: Jie1zhang

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

@@ -265,7 +265,7 @@ static void amdgpu_vm_bo_reset_state_machine(struct amdgpu_vm *vm)
 		vm_bo->moved = true;
 	spin_unlock(&vm->invalidated_lock);
 
-	amdgpu_vm_assert_locked(vm_bo->vm);
+	amdgpu_vm_assert_locked(vm);
 	list_for_each_entry_safe(vm_bo, tmp, &vm->idle, vm_status) {
 		struct amdgpu_bo *bo = vm_bo->bo;