7 files changed, 39 insertions, 14 deletions

diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index 388a929baf95..1a6a77df8a5e 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -265,6 +265,10 @@ void __init efi_init(void)
                                     (params.mmap & ~PAGE_MASK)));
 
         init_screen_info();
+
+        /* ARM does not permit early mappings to persist across paging_init() */
+        if (IS_ENABLED(CONFIG_ARM))
+                efi_memmap_unmap();
 }
 
 static int __init register_gop_device(void)
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 922cfb813109..a00934d263c5 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -110,7 +110,7 @@ static int __init arm_enable_runtime_services(void)
 {
         u64 mapsize;
 
-        if (!efi_enabled(EFI_BOOT) || !efi_enabled(EFI_MEMMAP)) {
+        if (!efi_enabled(EFI_BOOT)) {
                 pr_info("EFI services will not be available.\n");
                 return 0;
         }
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 249eb70691b0..fad7c62cfc0e 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -592,7 +592,11 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
 
                 early_memunmap(tbl, sizeof(*tbl));
         }
+        return 0;
+}
 
+int __init efi_apply_persistent_mem_reservations(void)
+{
         if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) {
                 unsigned long prsv = efi.mem_reserve;
 
@@ -963,36 +967,43 @@ bool efi_is_table_address(unsigned long phys_addr)
 }
 
 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
+static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
 
 int efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
 {
-        struct linux_efi_memreserve *rsv, *parent;
+        struct linux_efi_memreserve *rsv;
 
-        if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR)
+        if (!efi_memreserve_root)
                 return -ENODEV;
 
-        rsv = kmalloc(sizeof(*rsv), GFP_KERNEL);
+        rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC);
         if (!rsv)
                 return -ENOMEM;
 
-        parent = memremap(efi.mem_reserve, sizeof(*rsv), MEMREMAP_WB);
-        if (!parent) {
-                kfree(rsv);
-                return -ENOMEM;
-        }
-
         rsv->base = addr;
         rsv->size = size;
 
         spin_lock(&efi_mem_reserve_persistent_lock);
-        rsv->next = parent->next;
-        parent->next = __pa(rsv);
+        rsv->next = efi_memreserve_root->next;
+        efi_memreserve_root->next = __pa(rsv);
         spin_unlock(&efi_mem_reserve_persistent_lock);
 
-        memunmap(parent);
+        return 0;
+}
 
+static int __init efi_memreserve_root_init(void)
+{
+        if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR)
+                return -ENODEV;
+
+        efi_memreserve_root = memremap(efi.mem_reserve,
+                                       sizeof(*efi_memreserve_root),
+                                       MEMREMAP_WB);
+        if (!efi_memreserve_root)
+                return -ENOMEM;
         return 0;
 }
+early_initcall(efi_memreserve_root_init);
 
 #ifdef CONFIG_KEXEC
 static int update_efi_random_seed(struct notifier_block *nb,
diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 30ac0c975f8a..3d36142cf812 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -75,6 +75,9 @@ void install_memreserve_table(efi_system_table_t *sys_table_arg)
         efi_guid_t memreserve_table_guid = LINUX_EFI_MEMRESERVE_TABLE_GUID;
         efi_status_t status;
 
+        if (IS_ENABLED(CONFIG_ARM))
+                return;
+
         status = efi_call_early(allocate_pool, EFI_LOADER_DATA, sizeof(*rsv),
                                 (void **)&rsv);
         if (status != EFI_SUCCESS) {
diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 8830fa601e45..0c0d2312f4a8 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -158,6 +158,10 @@ static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
                         return efi_status;
                 }
         }
+
+        /* shrink the FDT back to its minimum size */
+        fdt_pack(fdt);
+
         return EFI_SUCCESS;
 
 fdt_set_fail:
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index fa2904fb841f..38b686c67b17 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -118,6 +118,9 @@ int __init efi_memmap_init_early(struct efi_memory_map_data *data)
 
 void __init efi_memmap_unmap(void)
 {
+        if (!efi_enabled(EFI_MEMMAP))
+                return;
+
         if (!efi.memmap.late) {
                 unsigned long size;
 
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
index a19d845bdb06..8903b9ccfc2b 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -67,7 +67,7 @@ struct efi_runtime_work efi_rts_work;
         }                                                               \
                                                                         \
         init_completion(&efi_rts_work.efi_rts_comp);                    \
-        INIT_WORK_ONSTACK(&efi_rts_work.work, efi_call_rts);            \
+        INIT_WORK(&efi_rts_work.work, efi_call_rts);                    \
         efi_rts_work.arg1 = _arg1;                                      \
         efi_rts_work.arg2 = _arg2;                                      \
         efi_rts_work.arg3 = _arg3;                                      \