aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/entry
diff options
context:
space:
mode:
authorAndy Lutomirski <luto@kernel.org>2019-07-01 20:43:20 -0700
committerThomas Gleixner <tglx@linutronix.de>2019-07-02 08:45:20 +0200
commitdffb3f9db6b593f3ed6ab4c8d8f10e0aa6aa7a88 (patch)
tree8f1baa91d005525e4a44c52886801e8978e3b54c /arch/x86/entry
parent9402eaf4c11f0b892eda7b2bcb4654ab34ce34f9 (diff)
downloadlinux-stericsson-dffb3f9db6b593f3ed6ab4c8d8f10e0aa6aa7a88.tar.gz
x86/entry/64: Don't compile ignore_sysret if 32-bit emulation is enabled
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/0f7dafa72fe7194689de5ee8cfe5d83509fabcf5.1562035429.git.luto@kernel.org
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/entry_64.S6
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 7f9f5119d6b1..54b1b0468b2b 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1743,11 +1743,17 @@ 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