Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull EFI fixes from Ingo Molnar:
 "Four fixes:
   - fix a kexec crash on arm64
   - fix a reboot crash on some Android platforms
   - future-proof the code for upcoming ACPI 6.2 changes
   - fix a build warning on x86"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efibc: Replace variable set function in notifier call
  x86/efi: fix a -Wtype-limits compilation warning
  efi/bgrt: Drop BGRT status field reserved bits check
  efi/memreserve: deal with memreserve entries in unmapped memory

3 files changed, 17 insertions, 12 deletions

diff --git a/drivers/firmware/efi/efi-bgrt.c b/drivers/firmware/efi/efi-bgrt.c
index a2384184a7de..b07c17643210 100644
--- a/drivers/firmware/efi/efi-bgrt.c
+++ b/drivers/firmware/efi/efi-bgrt.c
@@ -47,11 +47,6 @@ void __init efi_bgrt_init(struct acpi_table_header *table)
                        bgrt->version);
                 goto out;
         }
-        if (bgrt->status & 0xfe) {
-                pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n",
-                       bgrt->status);
-                goto out;
-        }
         if (bgrt->image_type != 0) {
                 pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n",
                        bgrt->image_type);
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 16b2137d117c..4b7cf7bc0ded 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -1009,14 +1009,16 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
 
         /* first try to find a slot in an existing linked list entry */
         for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) {
-                rsv = __va(prsv);
+                rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
                 index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
                 if (index < rsv->size) {
                         rsv->entry[index].base = addr;
                         rsv->entry[index].size = size;
 
+                        memunmap(rsv);
                         return 0;
                 }
+                memunmap(rsv);
         }
 
         /* no slot found - allocate a new linked list entry */
@@ -1024,7 +1026,13 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
         if (!rsv)
                 return -ENOMEM;
 
-        rsv->size = EFI_MEMRESERVE_COUNT(PAGE_SIZE);
+        /*
+         * The memremap() call above assumes that a linux_efi_memreserve entry
+         * never crosses a page boundary, so let's ensure that this remains true
+         * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
+         * using SZ_4K explicitly in the size calculation below.
+         */
+        rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
         atomic_set(&rsv->count, 1);
         rsv->entry[0].base = addr;
         rsv->entry[0].size = size;
diff --git a/drivers/firmware/efi/efibc.c b/drivers/firmware/efi/efibc.c
index 61e099826cbb..35dccc88ac0a 100644
--- a/drivers/firmware/efi/efibc.c
+++ b/drivers/firmware/efi/efibc.c
@@ -43,11 +43,13 @@ static int efibc_set_variable(const char *name, const char *value)
         efibc_str_to_str16(value, (efi_char16_t *)entry->var.Data);
         memcpy(&entry->var.VendorGuid, &guid, sizeof(guid));
 
-        ret = efivar_entry_set(entry,
-                               EFI_VARIABLE_NON_VOLATILE
-                               | EFI_VARIABLE_BOOTSERVICE_ACCESS
-                               | EFI_VARIABLE_RUNTIME_ACCESS,
-                               size, entry->var.Data, NULL);
+        ret = efivar_entry_set_safe(entry->var.VariableName,
+                                    entry->var.VendorGuid,
+                                    EFI_VARIABLE_NON_VOLATILE
+                                    | EFI_VARIABLE_BOOTSERVICE_ACCESS
+                                    | EFI_VARIABLE_RUNTIME_ACCESS,
+                                    false, size, entry->var.Data);
+
         if (ret)
                 pr_err("failed to set %s EFI variable: 0x%x\n",
                        name, ret);