[PATCH] x86/trapnr: Add event type macros to <asm/trapnr.h>

[PATCH] x86/trapnr: Add event type macros to <asm/trapnr.h>

[Xin Li]

Intel VT-x classifies events into eight different types, which is
inherited by FRED for event identification. As such, event type
becomes a common x86 concept, and should be defined in a common x86
header.

Add event type macros to <asm/trapnr.h>, and use it in <asm/vmx.h>.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
---
 arch/x86/include/asm/trapnr.h | 18 ++++++++++++++++++
 arch/x86/include/asm/vmx.h    | 17 +++++++++--------
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/trapnr.h b/arch/x86/include/asm/trapnr.h
index f5d2325aa0b7..356af7ceab4d 100644
--- a/arch/x86/include/asm/trapnr.h
+++ b/arch/x86/include/asm/trapnr.h
@@ -2,6 +2,24 @@
 #ifndef _ASM_X86_TRAPNR_H
 #define _ASM_X86_TRAPNR_H
 
+/*
+ * Event type codes used by both Intel VT-x and FRED
+ */
+/* Maskable external interrupt */
+#define EVENT_TYPE_HWINT	0
+#define EVENT_TYPE_RESERVED	1
+#define EVENT_TYPE_NMI		2
+/* Hardware exceptions (e.g., page fault) */
+#define EVENT_TYPE_HWFAULT	3
+/* Software interrupt (INT n) */
+#define EVENT_TYPE_SWINT	4
+/* INT1 (ICEBP) */
+#define EVENT_TYPE_PRIVSW	5
+/* Software exception (INT3 or INTO) */
+#define EVENT_TYPE_SWFAULT	6
+/* VT-x MTF or FRED SYSCALL/SYSENTER */
+#define EVENT_TYPE_OTHER	7
+
 /* Interrupts/Exceptions */
 
 #define X86_TRAP_DE		 0	/* Divide-by-zero */
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 0d02c4aafa6f..15a096fceb1d 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -17,6 +17,7 @@
 #include <linux/types.h>
 
 #include <uapi/asm/vmx.h>
+#include <asm/trapnr.h>
 #include <asm/vmxfeatures.h>
 
 #define VMCS_CONTROL_BIT(x)	BIT(VMX_FEATURE_##x & 0x1f)
@@ -374,14 +375,14 @@ enum vmcs_field {
 #define VECTORING_INFO_DELIVER_CODE_MASK    	INTR_INFO_DELIVER_CODE_MASK
 #define VECTORING_INFO_VALID_MASK       	INTR_INFO_VALID_MASK
 
-#define INTR_TYPE_EXT_INTR              (0 << 8) /* external interrupt */
-#define INTR_TYPE_RESERVED              (1 << 8) /* reserved */
-#define INTR_TYPE_NMI_INTR		(2 << 8) /* NMI */
-#define INTR_TYPE_HARD_EXCEPTION	(3 << 8) /* processor exception */
-#define INTR_TYPE_SOFT_INTR             (4 << 8) /* software interrupt */
-#define INTR_TYPE_PRIV_SW_EXCEPTION	(5 << 8) /* ICE breakpoint - undocumented */
-#define INTR_TYPE_SOFT_EXCEPTION	(6 << 8) /* software exception */
-#define INTR_TYPE_OTHER_EVENT           (7 << 8) /* other event */
+#define INTR_TYPE_EXT_INTR		(EVENT_TYPE_HWINT << 8)		/* external interrupt */
+#define INTR_TYPE_RESERVED		(EVENT_TYPE_RESERVED << 8)	/* reserved */
+#define INTR_TYPE_NMI_INTR		(EVENT_TYPE_NMI << 8)		/* NMI */
+#define INTR_TYPE_HARD_EXCEPTION	(EVENT_TYPE_HWFAULT << 8)	/* processor exception */
+#define INTR_TYPE_SOFT_INTR		(EVENT_TYPE_SWINT << 8)		/* software interrupt */
+#define INTR_TYPE_PRIV_SW_EXCEPTION	(EVENT_TYPE_PRIVSW << 8)	/* ICE breakpoint - undocumented */
+#define INTR_TYPE_SOFT_EXCEPTION	(EVENT_TYPE_SWFAULT << 8)	/* software exception */
+#define INTR_TYPE_OTHER_EVENT		(EVENT_TYPE_OTHER << 8)		/* other event */
 
 /* GUEST_INTERRUPTIBILITY_INFO flags. */
 #define GUEST_INTR_STATE_STI		0x00000001
-- 
2.34.1

Re: [PATCH] x86/trapnr: Add event type macros to <asm/trapnr.h>

[Peter Zijlstra]

On Wed, Jul 05, 2023 at 10:14:43PM -0700, Xin Li wrote:

> +/*
> + * Event type codes used by both Intel VT-x and FRED
> + */
> +/* Maskable external interrupt */
> +#define EVENT_TYPE_HWINT	0
> +#define EVENT_TYPE_RESERVED	1
> +#define EVENT_TYPE_NMI		2
> +/* Hardware exceptions (e.g., page fault) */
> +#define EVENT_TYPE_HWFAULT	3
> +/* Software interrupt (INT n) */
> +#define EVENT_TYPE_SWINT	4
> +/* INT1 (ICEBP) */
> +#define EVENT_TYPE_PRIVSW	5
> +/* Software exception (INT3 or INTO) */
> +#define EVENT_TYPE_SWFAULT	6
> +/* VT-x MTF or FRED SYSCALL/SYSENTER */
> +#define EVENT_TYPE_OTHER	7

So I know tglx hates on tail comments, but I find the below *MUCH* more
readable than the above horror show.

> -#define INTR_TYPE_EXT_INTR              (0 << 8) /* external interrupt */
> -#define INTR_TYPE_RESERVED              (1 << 8) /* reserved */
> -#define INTR_TYPE_NMI_INTR		(2 << 8) /* NMI */
> -#define INTR_TYPE_HARD_EXCEPTION	(3 << 8) /* processor exception */
> -#define INTR_TYPE_SOFT_INTR             (4 << 8) /* software interrupt */
> -#define INTR_TYPE_PRIV_SW_EXCEPTION	(5 << 8) /* ICE breakpoint - undocumented */
> -#define INTR_TYPE_SOFT_EXCEPTION	(6 << 8) /* software exception */
> -#define INTR_TYPE_OTHER_EVENT           (7 << 8) /* other event */

RE: [PATCH] x86/trapnr: Add event type macros to <asm/trapnr.h>

[Li, Xin3]

> > +/*
> > + * Event type codes used by both Intel VT-x and FRED  */
> > +/* Maskable external interrupt */
> > +#define EVENT_TYPE_HWINT	0
> > +#define EVENT_TYPE_RESERVED	1
> > +#define EVENT_TYPE_NMI		2
> > +/* Hardware exceptions (e.g., page fault) */
> > +#define EVENT_TYPE_HWFAULT	3
> > +/* Software interrupt (INT n) */
> > +#define EVENT_TYPE_SWINT	4
> > +/* INT1 (ICEBP) */
> > +#define EVENT_TYPE_PRIVSW	5
> > +/* Software exception (INT3 or INTO) */
> > +#define EVENT_TYPE_SWFAULT	6
> > +/* VT-x MTF or FRED SYSCALL/SYSENTER */
> > +#define EVENT_TYPE_OTHER	7
> 
> So I know tglx hates on tail comments, but I find the below *MUCH* more readable
> than the above horror show.

Agree, sometimes a tail comment looks much better.

Maybe tglx could give more specific directions on when it's okay to use
tail comments.

Thanks!
  Xin