From: Andy Lutomirski <luto@kernel.org> mainline inclusion from mainline-v5.3 commit dffb3f9db6b593f3ed6ab4c8d8f10e0aa6aa7a88 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5Q0UG?from=project-issue CVE: NA --------------------------- It's only used if !CONFIG_IA32_EMULATION, so disable it in normal configs. This will save a few bytes of text and reduce confusion. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "BaeChang Seok" <chang.seok.bae@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Bae, Chang Seok" <chang.seok.bae@intel.com> Link: https://lkml.kernel.org/r/0f7dafa72fe7194689de5ee8cfe5d83509fabcf5.156203542... Signed-off-by: tangbin <tangbin@cmss.chinamobile.com> --- arch/x86/entry/entry_64.S | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 323b395c9cd8..574edc97d5d9 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1732,11 +1732,17 @@ nmi_restore: iretq END(nmi) +#ifndef CONFIG_IA32_EMULATION +/* + * This handles SYSCALL from 32-bit code. There is no way to program + * MSRs to fully disable 32-bit SYSCALL. + */ ENTRY(ignore_sysret) UNWIND_HINT_EMPTY mov $-ENOSYS, %eax sysret END(ignore_sysret) +#endif ENTRY(rewind_stack_do_exit) UNWIND_HINT_FUNC -- 2.18.4