[2/4] ARM: mm: permit early_memremap() to be used in paging_init()

Commit Message

Ard Biesheuvel Dec. 10, 2018, 4:29 p.m. UTC

early_memremap() and early_ioremap() rely on early fixmap support,
which shares its virtual address space with kmap(), and so it is
taken down in paging_init().

In order to permit the EFI persistent memory reservation code to
use early_memremap() when called from paging_init(), move the call
to early_ioremap_reset() into paging_init(), right before the call
to early_fixmap_shutdown(), creating a window where we can add the
call to efi_apply_persistent_mem_reservations() in a subsequent patch.

Signed-off-by: Ard Biesheuvel <[e-mail]>
---
 arch/arm/kernel/setup.c | 2 --
 arch/arm/mm/mmu.c       | 2 ++
 2 files changed, 2 insertions(+), 2 deletions(-)

Patch

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 375b13f7e780..7e2a936a5ed0 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1124,8 +1124,6 @@  void __init setup_arch(char **cmdline_p)
 	/* Memory may have been removed so recalculate the bounds. */
 	adjust_lowmem_bounds();
 
-	early_ioremap_reset();
-
 	paging_init(mdesc);
 	request_standard_resources(mdesc);
 
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index f6bf6686559d..078f82f89fe5 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -22,6 +22,7 @@ 
 #include <asm/cputype.h>
 #include <asm/sections.h>
 #include <asm/cachetype.h>
+#include <asm/early_ioremap.h>
 #include <asm/fixmap.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
@@ -1628,6 +1629,7 @@  void __init paging_init(const struct machine_desc *mdesc)
 	memblock_set_current_limit(arm_lowmem_limit);
 	memblock_allow_resize();
 	dma_contiguous_remap();
+	early_ioremap_reset();
 	early_fixmap_shutdown();
 	devicemaps_init(mdesc);
 	kmap_init();