[PATCH 1/3] efi: Defer freeing boot services memory until after ACPI init

Josh Triplett
2012-08-30T21:28:43Z

Some new ACPI 5.0 tables reference resources stored in boot services
memory, so keep that memory around until we have ACPI and can extract
data from it.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
---
arch/x86/platform/efi/efi.c | 31 ++++++++++++++++++-------------
include/linux/efi.h | 1 +
init/main.c | 5 +++++
3 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 92660eda..8af329f 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -419,10 +419,21 @@ void __init efi_reserve_boot_services(void)
}
}

-static void __init efi_free_boot_services(void)
+void __init efi_unmap_memmap(void)
+{
+ if (memmap.map) {
+ early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
+ memmap.map = NULL;
+ }
+}
+
+void __init efi_free_boot_services(void)
{
void *p;

+ if (!efi_native)
+ return;
+
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
efi_memory_desc_t *md = p;
unsigned long long start = md->phys_addr;
@@ -438,6 +449,8 @@ static void __init efi_free_boot_services(void)

free_bootmem_late(start, size);
}
+
+ efi_unmap_memmap();
}

static int __init efi_systab_init(void *phys)
@@ -787,8 +800,10 @@ void __init efi_enter_virtual_mode(void)
* non-native EFI
*/

- if (!efi_native)
- goto out;
+ if (!efi_native) {
+ efi_unmap_memmap();
+ return;
+ }

/* Merge contiguous regions of the same type and attribute */
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
@@ -878,13 +893,6 @@ void __init efi_enter_virtual_mode(void)
}

/*
- * Thankfully, it does seem that no runtime services other than
- * SetVirtualAddressMap() will touch boot services code, so we can
- * get rid of it all at this point
- */
- efi_free_boot_services();
-
- /*
* Now that EFI is in virtual mode, update the function
* pointers in the runtime service table to the new virtual addresses.
*
@@ -906,9 +914,6 @@ void __init efi_enter_virtual_mode(void)
if (__supported_pte_mask & _PAGE_NX)
runtime_code_page_mkexec();

-out:
- early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
- memmap.map = NULL;
kfree(new_memmap);
}

diff --git a/include/linux/efi.h b/include/linux/efi.h
index ec45ccd..00ec70f 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -496,6 +496,7 @@ extern void efi_map_pal_code (void);
extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg);
extern void efi_gettimeofday (struct timespec *ts);
extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if possible */
+extern void efi_free_boot_services(void);
extern u64 efi_get_iobase (void);
extern u32 efi_mem_type (unsigned long phys_addr);
extern u64 efi_mem_attributes (unsigned long phys_addr);
diff --git a/init/main.c b/init/main.c
index b286730..391a291 100644
--- a/init/main.c
+++ b/init/main.c
@@ -631,6 +631,11 @@ asmlinkage void __init start_kernel(void)
acpi_early_init(); /* before LAPIC and SMP init */
sfi_init_late();

+#ifdef CONFIG_X86
+ if (efi_enabled)
+ efi_free_boot_services();
+#endif
+
ftrace_init();

/* Do the rest non-__init'ed, we're now alive */
--
1.7.10.4