[tip: x86/urgent] x86/msi: Fix msi message data shadow struct

[tip-bot2 for Reto Buerki]

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     59b18a1e65b7a2134814106d0860010e10babe18
Gitweb:        https://git.kernel.org/tip/59b18a1e65b7a2134814106d0860010e10babe18
Author:        Reto Buerki <reet@xxxxxxxxxxx>
AuthorDate:    Thu, 07 Apr 2022 13:06:47 +02:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 07 Apr 2022 15:19:32 +02:00

x86/msi: Fix msi message data shadow struct

The x86 MSI message data is 32 bits in total and is either in
compatibility or remappable format, see Intel Virtualization Technology
for Directed I/O, section 5.1.2.

Fixes: 6285aa50736 ("x86/msi: Provide msi message shadow structs")
Co-developed-by: Adrian-Ken Rueegsegger <ken@xxxxxxxxxxx>
Signed-off-by: Adrian-Ken Rueegsegger <ken@xxxxxxxxxxx>
Signed-off-by: Reto Buerki <reet@xxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20220407110647.67372-1-reet@xxxxxxxxxxx
---
 arch/x86/include/asm/msi.h | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/msi.h b/arch/x86/include/asm/msi.h
index b85147d..d71c7e8 100644
--- a/arch/x86/include/asm/msi.h
+++ b/arch/x86/include/asm/msi.h
@@ -12,14 +12,17 @@ int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
 /* Structs and defines for the X86 specific MSI message format */
 
 typedef struct x86_msi_data {
-	u32	vector			:  8,
-		delivery_mode		:  3,
-		dest_mode_logical	:  1,
-		reserved		:  2,
-		active_low		:  1,
-		is_level		:  1;
-
-	u32	dmar_subhandle;
+	union {
+		struct {
+			u32	vector			:  8,
+				delivery_mode		:  3,
+				dest_mode_logical	:  1,
+				reserved		:  2,
+				active_low		:  1,
+				is_level		:  1;
+		};
+		u32	dmar_subhandle;
+	};
 } __attribute__ ((packed)) arch_msi_msg_data_t;
 #define arch_msi_msg_data	x86_msi_data