diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | Documentation/x86/x86_64/uefi.txt | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/efi.c | 16 |
3 files changed, 21 insertions, 2 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index da13d6d1b2b0..795c487af8e4 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2150,6 +2150,9 @@ and is between 256 and 4096 characters. It is defined in the file usbhid.mousepoll= [USBHID] The interval which mice are to be polled at. + add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in + kernel's map of available physical RAM. + vdso= [X86-32,SH,x86-64] vdso=2: enable compat VDSO (default with COMPAT_VDSO) vdso=1: enable VDSO (default) diff --git a/Documentation/x86/x86_64/uefi.txt b/Documentation/x86/x86_64/uefi.txt index 7d77120a5184..a5e2b4fdb170 100644 --- a/Documentation/x86/x86_64/uefi.txt +++ b/Documentation/x86/x86_64/uefi.txt @@ -36,3 +36,7 @@ Mechanics: services. noefi turn off all EFI runtime services reboot_type=k turn off EFI reboot runtime service +- If the EFI memory map has additional entries not in the E820 map, + you can include those entries in the kernels memory map of available + physical RAM by using the following kernel command line parameter. + add_efi_memmap include EFI memory map of available physical RAM diff --git a/arch/x86/kernel/efi.c b/arch/x86/kernel/efi.c index a03ca36a302c..94382faeadb6 100644 --- a/arch/x86/kernel/efi.c +++ b/arch/x86/kernel/efi.c @@ -64,6 +64,17 @@ static int __init setup_noefi(char *arg) } early_param("noefi", setup_noefi); +int add_efi_memmap; +EXPORT_SYMBOL(add_efi_memmap); + +static int __init setup_add_efi_memmap(char *arg) +{ + add_efi_memmap = 1; + return 0; +} +early_param("add_efi_memmap", setup_add_efi_memmap); + + static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc) { return efi_call_virt2(get_time, tm, tc); @@ -219,7 +230,7 @@ unsigned long efi_get_time(void) * (zeropage) memory map. */ -static void __init add_efi_memmap(void) +static void __init do_add_efi_memmap(void) { void *p; @@ -406,7 +417,8 @@ void __init efi_init(void) if (memmap.desc_size != sizeof(efi_memory_desc_t)) printk(KERN_WARNING "Kernel-defined memdesc" "doesn't match the one from EFI!\n"); - add_efi_memmap(); + if (add_efi_memmap) + do_add_efi_memmap(); /* Setup for EFI runtime service */ reboot_type = BOOT_EFI; |