kvm: emulating exchange as write
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BUG: KMSAN: uninit-value in assign_eip_near arch/x86/kvm/emulate.c:829 [inline]
BUG: KMSAN: uninit-value in em_ret+0x124/0x130 arch/x86/kvm/emulate.c:2238
 assign_eip_near arch/x86/kvm/emulate.c:829 [inline]
 em_ret+0x124/0x130 arch/x86/kvm/emulate.c:2238
 x86_emulate_insn+0x1d87/0x5880 arch/x86/kvm/emulate.c:5292
 x86_emulate_instruction+0x13c9/0x30a0 arch/x86/kvm/x86.c:9181
 kvm_mmu_page_fault+0x1026/0x1140 arch/x86/kvm/mmu/mmu.c:5897
 handle_ept_violation+0x4ef/0x7f0 arch/x86/kvm/vmx/vmx.c:5796
 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6575 [inline]
 vmx_handle_exit+0x1b05/0x2140 arch/x86/kvm/vmx/vmx.c:6592
 vcpu_enter_guest arch/x86/kvm/x86.c:11077 [inline]
 vcpu_run arch/x86/kvm/x86.c:11181 [inline]
 kvm_arch_vcpu_ioctl_run+0x91e9/0xb890 arch/x86/kvm/x86.c:11407
 kvm_vcpu_ioctl+0xbfc/0x1770 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4447
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0x225/0x410 fs/ioctl.c:857
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Local variable eip created at:
 em_ret+0x37/0x130 arch/x86/kvm/emulate.c:2234
 x86_emulate_insn+0x1d87/0x5880 arch/x86/kvm/emulate.c:5292

CPU: 0 PID: 6007 Comm: syz-executor.4 Not tainted 6.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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