Re: [Xen-devel] [PATCH v3] SVM: Add union intstat_t for offset 68h in vmcb struct

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 26/03/2020 13:44, Pu Wen wrote:
> According to chapter "Appendix B Layout of VMCB" in the new version
> (v3.32) AMD64 APM[1], bit 1 of the VMCB offset 68h is defined as
> GUEST_INTERRUPT_MASK.
>
> In current xen codes, it use whole u64 interrupt_shadow to setup
> interrupt shadow, which will misuse other bit in VMCB offset 68h
> as part of interrupt_shadow, causing svm_get_interrupt_shadow() to
> mistake the guest having interrupts enabled as being in an interrupt
> shadow.  This has been observed to cause SeaBIOS to hang on boot.
>
> Add union intstat_t for VMCB offset 68h and fix codes to only use
> bit 0 as intr_shadow according to the new APM description.
>
> Reference:
> [1] https://www.amd.com/system/files/TechDocs/24593.pdf
>
> Signed-off-by: Pu Wen <puwen@xxxxxxxx>

Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Although thinking about it, renaming irq_stat to irq_state would
probably be a good move.  I can fix this on commit - no need to send a v4.

~Andrew