| Message ID | 20230802151704.2147028-1-ardb@kernel.org |
|---|---|
| State | Accepted |
| Commit | aba7e066c738d4b349413a271b2a236aa55bacbc |
| Headers | show |
| Series | [v2] efi/x86: Ensure that EFI_RUNTIME_MAP is enabled for kexec | expand |
On Wed, Aug 02, 2023 at 05:17:04PM +0200, Ard Biesheuvel wrote: > CONFIG_EFI_RUNTIME_MAP needs to be enabled in order for kexec to be able > to provide the required information about the EFI runtime mappings to > the incoming kernel, regardless of whether kexec_load() or > kexec_file_load() is being used. Without this information, kexec boot in > EFI mode is not possible. > > The CONFIG_EFI_RUNTIME_MAP option is currently directly configurable if > CONFIG_EXPERT is enabled, so that it can be turned on for debugging > purposes even if KEXEC is. However, the upshot of this is that it can s/is/isn't/ ? > also be disabled even when it shouldn't. > > So tweak the Kconfig declarations to avoid this situation. > > Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
On Wed, 2 Aug 2023 at 18:46, Kirill A . Shutemov <kirill.shutemov@linux.intel.com> wrote: > > On Wed, Aug 02, 2023 at 05:17:04PM +0200, Ard Biesheuvel wrote: > > CONFIG_EFI_RUNTIME_MAP needs to be enabled in order for kexec to be able > > to provide the required information about the EFI runtime mappings to > > the incoming kernel, regardless of whether kexec_load() or > > kexec_file_load() is being used. Without this information, kexec boot in > > EFI mode is not possible. > > > > The CONFIG_EFI_RUNTIME_MAP option is currently directly configurable if > > CONFIG_EXPERT is enabled, so that it can be turned on for debugging > > purposes even if KEXEC is. However, the upshot of this is that it can > > s/is/isn't/ ? > indeed, will fix.
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7422db4097701c96..bfbf53b49fee95a3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1955,6 +1955,7 @@ config EFI select UCS2_STRING select EFI_RUNTIME_WRAPPERS select ARCH_USE_MEMREMAP_PROT + select EFI_RUNTIME_MAP if KEXEC_CORE help This enables the kernel to use EFI runtime services that are available (such as the EFI variable services). @@ -2030,7 +2031,6 @@ config EFI_MAX_FAKE_MEM config EFI_RUNTIME_MAP bool "Export EFI runtime maps to sysfs" if EXPERT depends on EFI - default KEXEC_CORE help Export EFI runtime memory regions to /sys/firmware/efi/runtime-map. That memory map is required by the 2nd kernel to set up EFI virtual
CONFIG_EFI_RUNTIME_MAP needs to be enabled in order for kexec to be able to provide the required information about the EFI runtime mappings to the incoming kernel, regardless of whether kexec_load() or kexec_file_load() is being used. Without this information, kexec boot in EFI mode is not possible. The CONFIG_EFI_RUNTIME_MAP option is currently directly configurable if CONFIG_EXPERT is enabled, so that it can be turned on for debugging purposes even if KEXEC is. However, the upshot of this is that it can also be disabled even when it shouldn't. So tweak the Kconfig declarations to avoid this situation. Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- v2: use simpler conditional 'select EFI_RUNTIME_MAP' in CONFIG_EFI arch/x86/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)