1 files changed, 5 insertions, 5 deletions

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 65a0c1b48696..a84ac7b570e6 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -231,25 +231,25 @@ static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end)
                         continue;
                 if (*ptr > text_end)
                         continue;
-                text_poke(*ptr, ((unsigned char []){0xf0}), 1); /* add lock prefix */
+                /* turn DS segment override prefix into lock prefix */
+                text_poke(*ptr, ((unsigned char []){0xf0}), 1);
         };
 }
 
 static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
 {
         u8 **ptr;
-        char insn[1];
 
         if (noreplace_smp)
                 return;
 
-        add_nops(insn, 1);
         for (ptr = start; ptr < end; ptr++) {
                 if (*ptr < text)
                         continue;
                 if (*ptr > text_end)
                         continue;
-                text_poke(*ptr, insn, 1);
+                /* turn lock prefix into DS segment override prefix */
+                text_poke(*ptr, ((unsigned char []){0x3E}), 1);
         };
 }
 
@@ -444,7 +444,7 @@ void __init alternative_instructions(void)
                                             _text, _etext);
 
                 /* Only switch to UP mode if we don't immediately boot others */
-                if (num_possible_cpus() == 1 || setup_max_cpus <= 1)
+                if (num_present_cpus() == 1 || setup_max_cpus <= 1)
                         alternatives_smp_switch(0);
         }
 #endif