On Thu, Apr 01, 2021, Maxim Levitsky wrote:
> Use 'pending_exception' and 'injected_exception' fields
> to store the pending and the injected exceptions.
>
> After this patch still only one is active, but
> in the next patch both could co-exist in some cases.
Please explain _why_.
> Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 25 ++++--
> arch/x86/kvm/svm/nested.c | 26 +++---
> arch/x86/kvm/svm/svm.c | 6 +-
> arch/x86/kvm/vmx/nested.c | 36 ++++----
> arch/x86/kvm/vmx/vmx.c | 12 +--
> arch/x86/kvm/x86.c | 145 ++++++++++++++++++--------------
> arch/x86/kvm/x86.h | 6 +-
> 7 files changed, 143 insertions(+), 113 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index a52f973bdff6..3b2fd276e8d5 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -547,6 +547,14 @@ struct kvm_vcpu_xen {
> u64 runstate_times[4];
> };
>
> +struct kvm_queued_exception {
> + bool valid;
> + u8 nr;
If we're refactoring all this code anyways, maybe change "nr" to something a
bit more descriptive? E.g. vector.
> + bool has_error_code;
> + u32 error_code;
> +};
> +
> +
> struct kvm_vcpu_arch {
> /*
> * rip and regs accesses must go through
> @@ -645,16 +653,15 @@ struct kvm_vcpu_arch {
>
> u8 event_exit_inst_len;
>
> - struct kvm_queued_exception {
> - bool pending;
> - bool injected;
> - bool has_error_code;
> - u8 nr;
> - u32 error_code;
> - unsigned long payload;
> - bool has_payload;
> + struct kvm_queued_exception pending_exception;
> +
> + struct kvm_exception_payload {
> + bool valid;
> + unsigned long value;
> u8 nested_apf;
> - } exception;
> + } exception_payload;
Hmm, even if it's dead code at this time, I think the exception payload should
be part of 'struct kvm_queued_exception'. The payload is very much tied to a
single exception.
> +
> + struct kvm_queued_exception injected_exception;
Any objection to keeping the current syntax, arch.exception.{pending,injected}?
Maybe it's fear of change, but I like the current style, I think because the
relevant info is condensed at the end, e.g. I can ignore "vcpu->arch.exception"
and look at "pending.vector" or whatever. E.g.
struct {
struct kvm_queued_exception pending;
struct kvm_queued_exception injected;
} exception;
>
> struct kvm_queued_interrupt {
> bool injected;
