1 files changed, 16 insertions, 6 deletions

diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 85a343e28937..356170262a93 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -343,10 +343,11 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
                                 int (*get_ucode_data)(void *, const void *, size_t))
 {
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-        u8 *ucode_ptr = data, *new_mc = NULL, *mc;
+        u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
         int new_rev = uci->cpu_sig.rev;
         unsigned int leftover = size;
         enum ucode_state state = UCODE_OK;
+        unsigned int curr_mc_size = 0;
 
         while (leftover) {
                 struct microcode_header_intel mc_header;
@@ -361,9 +362,15 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
                         break;
                 }
 
-                mc = vmalloc(mc_size);
-                if (!mc)
-                        break;
+                /* For performance reasons, reuse mc area when possible */
+                if (!mc || mc_size > curr_mc_size) {
+                        if (mc)
+                                vfree(mc);
+                        mc = vmalloc(mc_size);
+                        if (!mc)
+                                break;
+                        curr_mc_size = mc_size;
+                }
 
                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
                     microcode_sanity_check(mc) < 0) {
@@ -376,13 +383,16 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
                                 vfree(new_mc);
                         new_rev = mc_header.rev;
                         new_mc  = mc;
-                } else
-                        vfree(mc);
+                        mc = NULL;      /* trigger new vmalloc */
+                }
 
                 ucode_ptr += mc_size;
                 leftover  -= mc_size;
         }
 
+        if (mc)
+                vfree(mc);
+
         if (leftover) {
                 if (new_mc)
                         vfree(new_mc);