From 47f71a8ccb0c881cf3d9e0b917ef5f0dc084b062 Mon Sep 17 00:00:00 2001 From: Eric Shelton Date: Thu, 23 May 2013 13:08:51 +0200 Subject: [PATCH] x86/EFI: fix boot for pre-UEFI systems efi/boot.c makes a call to QueryVariableInfo on all systems. However, as it is only promised for UEFI 2.0+ systems, pre-UEFI systems can hang or crash on this call. The below patch adds a version check, a technique used in other parts of the Xen EFI codebase. Signed-off-by: Eric Shelton Check runtime services version instead of EFI version (while generally they would be in sync, nothing requires them to be). Signed-off-by: Jan Beulich --- xen/arch/x86/efi/boot.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/efi/boot.c b/xen/arch/x86/efi/boot.c index 117a5cbe43..9718bd7df9 100644 --- a/xen/arch/x86/efi/boot.c +++ b/xen/arch/x86/efi/boot.c @@ -1241,12 +1241,14 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable) setup_efi_pci(); /* Get snapshot of variable store parameters. */ - status = efi_rs->QueryVariableInfo(EFI_VARIABLE_NON_VOLATILE | + status = (efi_rs->Hdr.Revision >> 16) >= 2 ? + efi_rs->QueryVariableInfo(EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS, &efi_boot_max_var_store_size, &efi_boot_remain_var_store_size, - &efi_boot_max_var_size); + &efi_boot_max_var_size) : + EFI_INCOMPATIBLE_VERSION; if ( EFI_ERROR(status) ) { efi_boot_max_var_store_size = 0; -- 2.30.2