[PATCH] x86/msi: Fix msi message data shadow struct

Reto Buerki
2022-04-07T11:07:41Z

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@codelabs.ch>
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Reto Buerki <reet@codelabs.ch>
---
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 b85147d75626..d71c7e8b738d 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

--
2.30.2