x86, 386 removal: Remove CONFIG_X86_POPAD_OK

The check_popad() routine tested for a 386-specific bug, and never
actually did anything useful with it anyway other than print a
message.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1354132230-21854-8-git-send-email-hpa@linux.intel.com

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index 159ee9c..423db71 100644 (file)
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -325,10 +325,6 @@ config X86_INVD_BUG
        def_bool y
        depends on M486
 
-config X86_POPAD_OK
-       def_bool y
-       depends on X86_32
-
 config X86_ALIGNMENT_16
        def_bool y
        depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2 || MGEODEGX1

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 0cd07cc..92dfec9 100644 (file)
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -106,33 +106,6 @@ static void __init check_hlt(void)
        pr_cont("OK\n");
 }
 
-/*
- *     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.
  *
@@ -157,7 +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();