Linus,
Please pull the latest efi-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus
# HEAD: c8f325a59cfc718d13a50fbc746ed9b415c25e92 efi/fdt: Avoid FDT manipulation after ExitBootServices()
Two EFI boot fixes, one for arm64 and one for x86 systems with certain firmware
versions.
Thanks,
Ingo
------------------>
Ard Biesheuvel (1):
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Jiri Kosina (1):
x86/efi: Always map the first physical page into the EFI pagetables
arch/x86/platform/efi/efi_64.c | 16 ++++++++++++++++
drivers/firmware/efi/libstub/fdt.c | 14 +++-----------
2 files changed, 19 insertions(+), 11 deletions(-)
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 319148bd4b05..2f25a363068c 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -269,6 +269,22 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
efi_scratch.use_pgd = true;
/*
+ * Certain firmware versions are way too sentimential and still believe
+ * they are exclusive and unquestionable owners of the first physical page,
+ * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
+ * (but then write-access it later during SetVirtualAddressMap()).
+ *
+ * Create a 1:1 mapping for this page, to avoid triple faults during early
+ * boot with such firmware. We are free to hand this page to the BIOS,
+ * as trim_bios_range() will reserve the first page and isolate it away
+ * from memory allocators anyway.
+ */
+ if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, _PAGE_RW)) {
+ pr_err("Failed to create 1:1 mapping for the first page!\n");
+ return 1;
+ }
+
+ /*
* When making calls to the firmware everything needs to be 1:1
* mapped and addressable with 32-bit pointers. Map the kernel
* text and allocate a new stack because we can't rely on the
diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 921dfa047202..260c4b4b492e 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -187,6 +187,7 @@ static efi_status_t update_fdt_memmap(void *fdt, struct efi_boot_memmap *map)
struct exit_boot_struct {
efi_memory_desc_t *runtime_map;
int *runtime_entry_count;
+ void *new_fdt_addr;
};
static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
@@ -202,7 +203,7 @@ static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
efi_get_virtmap(*map->map, *map->map_size, *map->desc_size,
p->runtime_map, p->runtime_entry_count);
- return EFI_SUCCESS;
+ return update_fdt_memmap(p->new_fdt_addr, map);
}
/*
@@ -300,22 +301,13 @@ efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
priv.runtime_map = runtime_map;
priv.runtime_entry_count = &runtime_entry_count;
+ priv.new_fdt_addr = (void *)*new_fdt_addr;
status = efi_exit_boot_services(sys_table, handle, &map, &priv,
exit_boot_func);
if (status == EFI_SUCCESS) {
efi_set_virtual_address_map_t *svam;
- status = update_fdt_memmap((void *)*new_fdt_addr, &map);
- if (status != EFI_SUCCESS) {
- /*
- * The kernel won't get far without the memory map, but
- * may still be able to print something meaningful so
- * return success here.
- */
- return EFI_SUCCESS;
- }
-
/* Install the new virtual address map */
svam = sys_table->runtime->set_virtual_address_map;
status = svam(runtime_entry_count * desc_size, desc_size,
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