3.18-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 2aa958c99c7fd3162b089a1a56a34a0cdb778de1 ] Kexec-ing a kernel with "efi=noruntime" on the first kernel's command line causes the following null pointer dereference: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 #PF error: [normal kernel read fault] Call Trace: efi_runtime_map_copy+0x28/0x30 bzImage64_load+0x688/0x872 arch_kexec_kernel_image_load+0x6d/0x70 kimage_file_alloc_init+0x13e/0x220 __x64_sys_kexec_file_load+0x144/0x290 do_syscall_64+0x55/0x1a0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Just skip the EFI info setup if EFI runtime services are not enabled. [ bp: Massage commit message. ] Suggested-by: Dave Young <dyoung@xxxxxxxxxx> Signed-off-by: Kairui Song <kasong@xxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Acked-by: Dave Young <dyoung@xxxxxxxxxx> Cc: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: bhe@xxxxxxxxxx Cc: David Howells <dhowells@xxxxxxxxxx> Cc: erik.schmauss@xxxxxxxxx Cc: fanc.fnst@xxxxxxxxxxxxxx Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: kexec@xxxxxxxxxxxxxxxxxxx Cc: lenb@xxxxxxxxxx Cc: linux-acpi@xxxxxxxxxxxxxxx Cc: Philipp Rudo <prudo@xxxxxxxxxxxxxxxxxx> Cc: rafael.j.wysocki@xxxxxxxxx Cc: robert.moore@xxxxxxxxx Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: x86-ml <x86@xxxxxxxxxx> Cc: Yannik Sembritzki <yannik@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20190118111310.29589-2-kasong@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/kernel/kexec-bzimage64.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index ca05f86481aa..3e22751382c3 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -167,6 +167,9 @@ setup_efi_state(struct boot_params *params, unsigned long params_load_addr, struct efi_info *current_ei = &boot_params.efi_info; struct efi_info *ei = ¶ms->efi_info; + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return 0; + if (!current_ei->efi_memmap_size) return 0; -- 2.19.1
