diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index ec548e9..a46bcf4 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c

@@ -13,11 +13,14 @@
 #include <linux/linkage.h>
 #include <linux/init.h>
 #include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/swiotlb.h>
 
 #include <asm/tlbflush.h>
 #include <asm/fixmap.h>
 #include <asm/setup.h>
 #include <asm/bootparam.h>
+#include <asm/cacheflush.h>
 
 extern pmdval_t early_pmd_flags;
 int __init __early_make_pgtable(unsigned long, pmdval_t);

@@ -192,3 +195,22 @@ void __init sme_early_init(void)
 	for (i = 0; i < ARRAY_SIZE(protection_map); i++)
 		protection_map[i] = pgprot_encrypted(protection_map[i]);
 }
+
+/* Architecture __weak replacement functions */
+void __init mem_encrypt_init(void)
+{
+	if (!sme_me_mask)

+
+	/* Make the SWIOTLB buffer area decrypted */
+	set_memory_decrypted((unsigned long)vaddr, size >> PAGE_SHIFT);
+}

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 4ee479f..15e7160 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h

@@ -35,6 +35,7 @@ enum swiotlb_force {
 extern unsigned long swiotlb_nr_tbl(void);
 unsigned long swiotlb_size_or_default(void);
 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
+extern void __init swiotlb_update_mem_attributes(void);
 
 /*
  * Enumeration for sync targets

diff --git a/init/main.c b/init/main.c
index 8222caa..ba13f8f 100644
--- a/init/main.c
+++ b/init/main.c

@@ -466,6 +466,10 @@ void __init __weak thread_stack_cache_init(void)
 }
 #endif
 
+void __init __weak mem_encrypt_init(void)
+{
+}
+
 /*
  * Set up kernel memory allocators
  */

@@ -614,6 +618,15 @@ asmlinkage __visible void __init start_kernel(void)
 	 */
 	locking_selftest();
 
+	/*
+	 * This needs to be called before any devices perform DMA
+	 * operations that might use the swiotlb bounce buffers.

+	 * This call will mark the bounce buffers as decrypted so
+	 * that their usage will not cause "plain-text" data to be
+	 * decrypted when accessed.
+	 */
+	mem_encrypt_init();
+
 #ifdef CONFIG_BLK_DEV_INITRD
 	if (initrd_start && !initrd_below_start_ok &&
 	    page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index a8d74a7..c463067 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c

@@ -30,6 +30,7 @@
 #include <linux/highmem.h>
 #include <linux/gfp.h>
 #include <linux/scatterlist.h>
+#include <linux/mem_encrypt.h>
 
 #include <asm/io.h>
 #include <asm/dma.h>

@@ -155,6 +156,17 @@ unsigned long swiotlb_size_or_default(void)
 	return size ? size : (IO_TLB_DEFAULT_SIZE);
 }
 
+void __weak swiotlb_set_mem_attributes(void *vaddr, unsigned long size)
+{
+}
+
+/* For swiotlb, clear memory encryption mask from dma addresses */
+static dma_addr_t swiotlb_phys_to_dma(struct device *hwdev,
+				      phys_addr_t address)
+{
+	return phys_to_dma(hwdev, address) & ~sme_me_mask;
+}
+
 /* Note that this doesn't work with highmem page */
 static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
 				      volatile void *address)

@@ -183,6 +195,31 @@ void swiotlb_print_info(void)
 	       bytes >> 20, vstart, vend - 1);
 }
 
+/*
+ * Early SWIOTLB allocation may be to early to allow an architecture to