Merge branch 'x86-nuke386-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull "Nuke 386-DX/SX support" from Ingo Molnar:
 "This tree removes ancient-386-CPUs support and thus zaps quite a bit
  of complexity:

    24 files changed, 56 insertions(+), 425 deletions(-)

  ... which complexity has plagued us with extra work whenever we wanted
  to change SMP primitives, for years.

  Unfortunately there's a nostalgic cost: your old original 386 DX33
  system from early 1991 won't be able to boot modern Linux kernels
  anymore.  Sniff."

I'm not sentimental.  Good riddance.

* 'x86-nuke386-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, 386 removal: Document Nx586 as a 386 and thus unsupported
  x86, cleanups: Simplify sync_core() in the case of no CPUID
  x86, 386 removal: Remove CONFIG_X86_POPAD_OK
  x86, 386 removal: Remove CONFIG_X86_WP_WORKS_OK
  x86, 386 removal: Remove CONFIG_INVLPG
  x86, 386 removal: Remove CONFIG_BSWAP
  x86, 386 removal: Remove CONFIG_XADD
  x86, 386 removal: Remove CONFIG_CMPXCHG
  x86, 386 removal: Remove CONFIG_M386 from Kconfig

1 files changed, 2 insertions, 39 deletions

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index d0e910da16c5..92dfec986a48 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -107,53 +107,17 @@ static void __init check_hlt(void)
 }
 
 /*
- *	Most 386 processors have a bug where a POPAD can lock the
- *	machine even from user space.
- */
-
-static void __init check_popad(void)
-{
-#ifndef CONFIG_X86_POPAD_OK
-	int res, inp = (int) &res;
-
-	pr_info("Checking for popad bug... ");
-	__asm__ __volatile__(
-	  "movl $12345678,%%eax; movl $0,%%edi; pusha; popa; movl (%%edx,%%edi),%%ecx "
-	  : "=&a" (res)
-	  : "d" (inp)
-	  : "ecx", "edi");
-	/*
-	 * If this fails, it means that any user program may lock the
-	 * CPU hard. Too bad.
-	 */
-	if (res != 12345678)
-		pr_cont("Buggy\n");
-	else
-		pr_cont("OK\n");
-#endif
-}
-
-/*
  * Check whether we are able to run this kernel safely on SMP.
  *
- * - In order to run on a i386, we need to be compiled for i386
- *   (for due to lack of "invlpg" and working WP on a i386)
+ * - i386 is no longer supported.
  * - In order to run on anything without a TSC, we need to be
  *   compiled for a i486.
  */
 
 static void __init check_config(void)
 {
-/*
- * We'd better not be a i386 if we're configured to use some
- * i486+ only features! (WP works in supervisor mode and the
- * new "invlpg" and "bswap" instructions)
- */
-#if defined(CONFIG_X86_WP_WORKS_OK) || defined(CONFIG_X86_INVLPG) || \
-	defined(CONFIG_X86_BSWAP)
-	if (boot_cpu_data.x86 == 3)
+	if (boot_cpu_data.x86 < 4)
 		panic("Kernel requires i486+ for 'invlpg' and other features");
-#endif
 }
 
 
@@ -166,7 +130,6 @@ void __init check_bugs(void)
 #endif
 	check_config();
 	check_hlt();
-	check_popad();
 	init_utsname()->machine[1] =
 		'0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86);
 	alternative_instructions();