Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Reto Buerki <reet@codelabs.ch>
To:     tglx@linutronix.de, dwmw2@infradead.org
Cc:     x86@kernel.org, kvm@vger.kernel.org,
        iommu@lists.linux-foundation.org, joro@8bytes.org,
        pbonzini@redhat.com, linux-kernel@vger.kernel.org,
        linux-hyperv@vger.kernel.org, maz@misterjones.org,
        decui@microsoft.com
Subject: [PATCH] x86/msi: Fix msi message data shadow struct
Date:   Thu,  7 Apr 2022 13:06:47 +0200
Message-Id: <20220407110647.67372-1-reet@codelabs.ch>
In-Reply-To: <87pmltzwtr.ffs@tglx>
References: <87pmltzwtr.ffs@tglx>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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