3.5.7.7 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Matt Fleming <[email protected]> commit fb834c7acc5e140cf4f9e86da93a66de8c0514da upstream. commit 1de63d60cd5b ("efi: Clear EFI_RUNTIME_SERVICES rather than EFI_BOOT by "noefi" boot parameter") attempted to make "noefi" true to its documentation and disable EFI runtime services to prevent the bricking bug described in commit e0094244e41c ("samsung-laptop: Disable on EFI hardware"). However, it's not possible to clear EFI_RUNTIME_SERVICES from an early param function because EFI_RUNTIME_SERVICES is set in efi_init() *after* parse_early_param(). This resulted in "noefi" effectively becoming a no-op and no longer providing users with a way to disable EFI, which is bad for those users that have buggy machines. Reported-by: Walt Nelson Jr <[email protected]> Cc: Satoru Takeuchi <[email protected]> Signed-off-by: Matt Fleming <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: H. Peter Anvin <[email protected]> Signed-off-by: Luis Henriques <[email protected]> --- arch/x86/platform/efi/efi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 3705bb0..1e40637 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -84,9 +84,10 @@ int efi_enabled(int facility) } EXPORT_SYMBOL(efi_enabled); +static bool disable_runtime = false; static int __init setup_noefi(char *arg) { - clear_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility); + disable_runtime = true; return 0; } early_param("noefi", setup_noefi); @@ -733,7 +734,7 @@ void __init efi_init(void) if (!efi_is_native()) pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n"); else { - if (efi_runtime_init()) + if (disable_runtime || efi_runtime_init()) return; set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility); } -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
