Merge tag 'tpmdd-next-20190625' of git://git.infradead.org/users/jjs/linux-tpmdd

[linux-2.6-microblaze.git] / drivers / firmware / efi / efi.c

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index a449e64..ad3b1f4 100644 (file)
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -1011,14 +1011,16 @@ 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 */
@@ -1026,7 +1028,13 @@ 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;