[kvm-unit-tests PATCH v3 15/18] arm64: efi: Don't map reserved regions

[Andrew Jones <andrew.jones@linux.dev>]

We shouldn't need to map all the regions that the EFI memory map
contains. Just map EFI_LOADER_CODE and EFI_LOADER_DATA, since
those are for the loaded unit test, and any region types which
could be used by the unit test for its own memory allocations. We
still map EFI_BOOT_SERVICES_DATA since the primary stack is on a
region of that type. In a later patch we'll switch to a stack we
allocate ourselves to drop that one too.

Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
---
 lib/arm/mmu.c    | 6 +-----
 lib/arm/setup.c  | 4 ++--
 lib/memregions.c | 8 ++++++++
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c
index eb5e82a95f06..9dce7da85709 100644
--- a/lib/arm/mmu.c
+++ b/lib/arm/mmu.c
@@ -221,12 +221,8 @@ void *setup_mmu(phys_addr_t phys_end, void *unused)
 		mmu_idmap = alloc_page();
 
 	for (r = mem_regions; r->end; ++r) {
-		if (r->flags & MR_F_IO) {
+		if (r->flags & (MR_F_IO | MR_F_RESERVED)) {
 			continue;
-		} else if (r->flags & MR_F_RESERVED) {
-			/* Reserved pages need to be writable for whatever reserved them */
-			mmu_set_range_ptes(mmu_idmap, r->start, r->start, r->end,
-					   __pgprot(PTE_WBWA));
 		} else if (r->flags & MR_F_CODE) {
 			/* armv8 requires code shared between EL1 and EL0 to be read-only */
 			mmu_set_range_ptes(mmu_idmap, r->start, r->start, r->end,
diff --git a/lib/arm/setup.c b/lib/arm/setup.c
index f5dbb48e721a..50a3bb65d865 100644
--- a/lib/arm/setup.c
+++ b/lib/arm/setup.c
@@ -309,8 +309,8 @@ static efi_status_t efi_mem_init(efi_bootinfo_t *efi_bootinfo)
 		data->flags &= ~MR_F_CODE;
 
 	for (struct mem_region *m = mem_regions; m->end; ++m) {
-		if (m != code && (m->flags & MR_F_CODE))
-			m->flags = MR_F_RESERVED;
+		if (m != code)
+			assert(!(m->flags & MR_F_CODE));
 
 		if (!(m->flags & MR_F_IO)) {
 			if (m->start < __phys_offset)
diff --git a/lib/memregions.c b/lib/memregions.c
index 9cdbb639ab62..3c6f751eb4f2 100644
--- a/lib/memregions.c
+++ b/lib/memregions.c
@@ -112,6 +112,14 @@ void memregions_efi_init(struct efi_boot_memmap *mem_map,
 		case EFI_LOADER_CODE:
 			r.flags = MR_F_CODE;
 			break;
+		case EFI_LOADER_DATA:
+			break;
+		case EFI_BOOT_SERVICES_DATA:
+			/*
+			 * FIXME: This would ideally be MR_F_RESERVED, but the
+			 * primary stack is in a region of this EFI type.
+			 */
+			break;
 		case EFI_PERSISTENT_MEMORY:
 			r.flags = MR_F_PERSISTENT;
 			break;
-- 
2.44.0