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From:   Pankaj Gupta <pankaj.gupta@amd.com>
To:     <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>
CC:     <dan.j.williams@intel.com>, <thomas.lendacky@amd.com>,
        <pankaj.gupta@amd.com>
Subject: [PATCH] mm/memremap.c: map FS_DAX device memory as decrypted
Date:   Wed, 2 Nov 2022 11:07:28 -0500
Message-ID: <20221102160728.3184016-1-pankaj.gupta@amd.com>
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virtio_pmem use devm_memremap_pages() to map the device memory.
By default this memory is mapped as encrypted with SEV. Guest
reboot changes the current encryption key and guest no longer
properly decrypts the FSDAX device meta data.

Mark the corresponding device memory region for FSDAX devices
(mapped with memremap_pages) as decrypted to retain the persistent
memory property.

Signed-off-by: Pankaj Gupta <pankaj.gupta@amd.com>
---
 mm/memremap.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/memremap.c b/mm/memremap.c
index 421bec3a29ee..08cbf54fe037 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -335,6 +335,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
 			WARN(1, "File system DAX not supported\n");
 			return ERR_PTR(-EINVAL);
 		}
+		params.pgprot = pgprot_decrypted(params.pgprot);
 		break;
 	case MEMORY_DEVICE_GENERIC:
 		break;
-- 
2.34.1