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From:   David Woodhouse <dwmw2@infradead.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Tom Lendacky <thomas.lendacky@amd.com>,
        Borislav Petkov <bp@alien8.de>, linux-kernel@vger.kernel.org,
        x86 <x86@kernel.org>, Qian Cai <cai@redhat.com>,
        Joerg Roedel <joro@8bytes.org>
Subject: [PATCH 2/3] iommu/amd: Fix union of bitfields in intcapxt support
Date:   Wed, 11 Nov 2020 14:43:21 +0000
Message-Id: <20201111144322.1659970-2-dwmw2@infradead.org>
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 <20201111144322.1659970-1-dwmw2@infradead.org>
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From: David Woodhouse <dwmw@amazon.co.uk>

All the bitfields in here are overlaid on top of each other since
they're a union. Change the second u64 to be in a struct so it does
the intended thing.

Fixes: b5c3786ee3704 ("iommu/amd: Use msi_msg shadow structs")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
 drivers/iommu/amd/init.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 90a8add186e0..a94b96f1e13a 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -1969,13 +1969,15 @@ static int iommu_setup_msi(struct amd_iommu *iommu)
 
 union intcapxt {
 	u64	capxt;
-	u64	reserved_0		:  2,
-		dest_mode_logical	:  1,
-		reserved_1		:  5,
-		destid_0_23		: 24,
-		vector			:  8,
-		reserved_2		: 16,
-		destid_24_31		:  8;
+	struct {
+		u64	reserved_0		:  2,
+			dest_mode_logical	:  1,
+			reserved_1		:  5,
+			destid_0_23		: 24,
+			vector			:  8,
+			reserved_2		: 16,
+			destid_24_31		:  8;
+	};
 } __attribute__ ((packed));
 
 /*
-- 
2.26.2