[PATCH 4.14 055/159] x86/entry/64: Shorten TEST instructions
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2017-12-22 09:37:11
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4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Borislav Petkov <redacted> commit 1e4c4f610f774df6088d7c065b2dd4d22adba698 upstream. Convert TESTL to TESTB and save 3 bytes per callsite. No functionality change. Signed-off-by: Borislav Petkov <redacted> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <redacted> Cc: Dave Hansen <redacted> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <redacted> Link: http://lkml.kernel.org/r/20171102120926.4srwerqrr7g72e2k@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- arch/x86/entry/entry_64.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S@@ -621,7 +621,7 @@ GLOBAL(retint_user) GLOBAL(swapgs_restore_regs_and_return_to_usermode) #ifdef CONFIG_DEBUG_ENTRY /* Assert that pt_regs indicates user mode. */ - testl $3, CS(%rsp) + testb $3, CS(%rsp) jnz 1f ud2 1:
@@ -654,7 +654,7 @@ retint_kernel: GLOBAL(restore_regs_and_return_to_kernel) #ifdef CONFIG_DEBUG_ENTRY /* Assert that pt_regs indicates kernel mode. */ - testl $3, CS(%rsp) + testb $3, CS(%rsp) jz 1f ud2 1: