x86/kaslr: Eliminate 'start_orig' local variable from __process_mem_region()

Set the region.size within the loop, which removes the need for
start_orig.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-8-nivedita@alum.mit.edu

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index f2454ee..e978c35 100644 (file)
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -623,7 +623,7 @@ static void __process_mem_region(struct mem_vector *entry,
                                 unsigned long image_size)
 {
        struct mem_vector region, overlap;
-       unsigned long start_orig, end;
+       unsigned long end;
 
        /* Ignore entries entirely below our minimum. */
        if (entry->start + entry->size < minimum)
@@ -635,12 +635,9 @@ static void __process_mem_region(struct mem_vector *entry,
                return;
 
        region.start = entry->start;
-       region.size = end - entry->start;
 
        /* Give up if slot area array is full. */
        while (slot_area_index < MAX_SLOT_AREA) {
-               start_orig = region.start;
-
                /* Potentially raise address to minimum location. */
                if (region.start < minimum)
                        region.start = minimum;
@@ -653,7 +650,7 @@ static void __process_mem_region(struct mem_vector *entry,
                        return;
 
                /* Reduce size by any delta from the original address. */
-               region.size -= region.start - start_orig;
+               region.size = end - region.start;
 
                /* Return if region can't contain decompressed kernel */
                if (region.size < image_size)
@@ -679,7 +676,6 @@ static void __process_mem_region(struct mem_vector *entry,
                        return;
 
                /* Clip off the overlapping region and start over. */
-               region.size -= overlap.start - region.start + overlap.size;
                region.start = overlap.start + overlap.size;
        }
 }