The patch titled
     Allow boot-time disable of SMP altinstructions
has been added to the -mm tree.  Its filename is
     allow-boot-time-disable-of-smp-altinstructions.patch

*** Remember to use Documentation/SubmitChecklist when testing your code ***

See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this

------------------------------------------------------
Subject: Allow boot-time disable of SMP altinstructions
From: Jeremy Fitzhardinge <[EMAIL PROTECTED]>

Add "noreplace-smp" to disable SMP instruction replacement.

Signed-off-by: Jeremy Fitzhardinge <[EMAIL PROTECTED]>
Cc: Andi Kleen <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 Documentation/kernel-parameters.txt |    6 ++++++
 arch/i386/kernel/alternative.c      |   23 +++++++++++++++++++----
 2 files changed, 25 insertions(+), 4 deletions(-)

diff -puN 
Documentation/kernel-parameters.txt~allow-boot-time-disable-of-smp-altinstructions
 Documentation/kernel-parameters.txt
--- 
a/Documentation/kernel-parameters.txt~allow-boot-time-disable-of-smp-altinstructions
+++ a/Documentation/kernel-parameters.txt
@@ -1135,6 +1135,9 @@ and is between 256 and 4096 characters. 
 
        nomce           [IA-32] Machine Check Exception
 
+       noreplace-smp   [IA-32,SMP] Don't replace SMP instructions
+                       with UP alternatives
+
        noresidual      [PPC] Don't use residual data on PReP machines.
 
        noresume        [SWSUSP] Disables resume and restores original swap
@@ -1540,6 +1543,9 @@ and is between 256 and 4096 characters. 
        smart2=         [HW]
                        Format: <io1>[,<io2>[,...,<io8>]]
 
+       smp-alt-once    [IA-32,SMP] On a hotplug CPU system, only
+                       attempt to substitute SMP alternatives once at boot.
+
        snd-ad1816a=    [HW,ALSA]
 
        snd-ad1848=     [HW,ALSA]
diff -puN 
arch/i386/kernel/alternative.c~allow-boot-time-disable-of-smp-altinstructions 
arch/i386/kernel/alternative.c
--- 
a/arch/i386/kernel/alternative.c~allow-boot-time-disable-of-smp-altinstructions
+++ a/arch/i386/kernel/alternative.c
@@ -5,6 +5,7 @@
 #include <asm/alternative.h>
 #include <asm/sections.h>
 
+static int noreplace_smp     = 0;
 static int smp_alt_once      = 0;
 static int debug_alternative = 0;
 
@@ -13,15 +14,23 @@ static int __init bootonly(char *str)
        smp_alt_once = 1;
        return 1;
 }
+__setup("smp-alt-boot", bootonly);
+
 static int __init debug_alt(char *str)
 {
        debug_alternative = 1;
        return 1;
 }
-
-__setup("smp-alt-boot", bootonly);
 __setup("debug-alternative", debug_alt);
 
+static int __init setup_noreplace_smp(char *str)
+{
+       noreplace_smp = 1;
+       return 1;
+}
+__setup("noreplace-smp", setup_noreplace_smp);
+
+
 #define DPRINTK(fmt, args...) if (debug_alternative) \
        printk(KERN_DEBUG fmt, args)
 
@@ -185,6 +194,9 @@ static void alternatives_smp_unlock(u8 *
 {
        u8 **ptr;
 
+       if (noreplace_smp)
+               return;
+
        for (ptr = start; ptr < end; ptr++) {
                if (*ptr < text)
                        continue;
@@ -219,6 +231,9 @@ void alternatives_smp_module_add(struct 
        struct smp_alt_module *smp;
        unsigned long flags;
 
+       if (noreplace_smp)
+               return;
+
        if (smp_alt_once) {
                if (boot_cpu_has(X86_FEATURE_UP))
                        alternatives_smp_unlock(locks, locks_end,
@@ -253,7 +268,7 @@ void alternatives_smp_module_del(struct 
        struct smp_alt_module *item;
        unsigned long flags;
 
-       if (smp_alt_once)
+       if (smp_alt_once || noreplace_smp)
                return;
 
        spin_lock_irqsave(&smp_alt, flags);
@@ -284,7 +299,7 @@ void alternatives_smp_switch(int smp)
        return;
 #endif
 
-       if (smp_alt_once)
+       if (noreplace_smp || smp_alt_once)
                return;
        BUG_ON(!smp && (num_online_cpus() > 1));
 
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

re-enable-vdso-by-default-with-paravirt.patch
remove-noreplacement-option.patch
remove-smp_alt_instructions.patch
rename-the-parainstructions-symbols-to-be-consistent-with-the-others.patch
allow-boot-time-disable-of-smp-altinstructions.patch
allow-boot-time-disable-of-paravirt_ops-patching.patch
fixes-and-cleanups-for-earlyprintk-aka-boot-console.patch
ignore-stolen-time-in-the-softlockup-watchdog.patch
add-touch_all_softlockup_watchdogs.patch
clean-up-elf-note-generation.patch

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