From 8e65f6e03a90927b8de16c15da976baa6c3fff69 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 18 Jan 2015 12:35:55 +0100 Subject: [PATCH] x86/entry_32: Convert X86_INVD_BUG to ALTERNATIVE macro Booting a 486 kernel on an AMD guest with this patch applied, says: apply_alternatives: feat: 0*32+25, old: (c160a475, len: 5), repl: (c19557d4, len: 5) c160a475: alt_insn: 68 10 35 00 c1 c19557d4: rpl_insn: 68 80 39 00 c1 which is: old insn VA: 0xc160a475, CPU feat: X86_FEATURE_XMM, size: 5 simd_coprocessor_error: c160a475: 68 10 35 00 c1 push $0xc1003510 repl insn: 0xc19557d4, size: 5 c160a475: 68 80 39 00 c1 push $0xc1003980 Signed-off-by: Borislav Petkov --- arch/x86/kernel/entry_32.S | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index d23c9a1d40e1..b910577d1ff9 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -816,15 +816,9 @@ ENTRY(simd_coprocessor_error) pushl_cfi $0 #ifdef CONFIG_X86_INVD_BUG /* AMD 486 bug: invd from userspace calls exception 19 instead of #GP */ -661: pushl_cfi $do_general_protection -662: -.section .altinstructions,"a" - altinstruction_entry 661b, 663f, X86_FEATURE_XMM, 662b-661b, 664f-663f, 0 -.previous -.section .altinstr_replacement,"ax" -663: pushl $do_simd_coprocessor_error -664: -.previous + ALTERNATIVE "pushl_cfi $do_general_protection", \ + "pushl $do_simd_coprocessor_error", \ + X86_FEATURE_XMM #else pushl_cfi $do_simd_coprocessor_error #endif