Section 1.9 of TLFS v6.0b says: "All structures are padded in such a way that fields are aligned naturally (that is, an 8-byte field is aligned to an offset of 8 bytes and so on)". 'struct enlightened_vmcs' has a glitch: ... struct { u32 nested_flush_hypercall:1; /* 836: 0 4 */ u32 msr_bitmap:1; /* 836: 1 4 */ u32 reserved:30; /* 836: 2 4 */ } hv_enlightenments_control; /* 836 4 */ u32 hv_vp_id; /* 840 4 */ u64 hv_vm_id; /* 844 8 */ u64 partition_assist_page; /* 852 8 */ ... And the observed values in 'partition_assist_page' make no sense at all. Fix the layout by padding the structure properly. Fixes: 68d1eb72ee99 ("x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits") Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> --- arch/x86/include/asm/hyperv-tlfs.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h index 5225a85c08c3..e7ddae8e02c6 100644 --- a/arch/x86/include/asm/hyperv-tlfs.h +++ b/arch/x86/include/asm/hyperv-tlfs.h @@ -548,7 +548,7 @@ struct hv_enlightened_vmcs { u64 guest_rip; u32 hv_clean_fields; - u32 hv_padding_32; + u32 padding32_1; u32 hv_synthetic_controls; struct { u32 nested_flush_hypercall:1; @@ -556,7 +556,7 @@ struct hv_enlightened_vmcs { u32 reserved:30; } __packed hv_enlightenments_control; u32 hv_vp_id; - + u32 padding32_2; u64 hv_vm_id; u64 partition_assist_page; u64 padding64_4[4]; -- 2.35.3