x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'

Since 'run_size' is now calculated in misc.c, the old script and associated
argument passing is no longer needed. This patch removes them, and renames
'run_size' to the more descriptive 'kernel_total_size'.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog, renamed 'run_size' to 'kernel_total_size' ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-6-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index cda93d1..bee6238 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -340,9 +340,9 @@
 				  unsigned char *input_data,
 				  unsigned long input_len,
 				  unsigned char *output,
-				  unsigned long output_len,
-				  unsigned long run_size)
+				  unsigned long output_len)
 {
+	const unsigned long kernel_total_size = VO__end - VO__text;
 	unsigned char *output_orig = output;
 
 	/* Retain x86 boot parameters pointer passed from startup_32/64. */
@@ -364,8 +364,6 @@
 	lines = boot_params->screen_info.orig_video_lines;
 	cols = boot_params->screen_info.orig_video_cols;
 
-	run_size = VO__end - VO__text;
-
 	console_init();
 	debug_putstr("early console in extract_kernel\n");
 
@@ -377,7 +375,7 @@
 	debug_putaddr(input_len);
 	debug_putaddr(output);
 	debug_putaddr(output_len);
-	debug_putaddr(run_size);
+	debug_putaddr(kernel_total_size);
 
 	/*
 	 * The memory hole needed for the kernel is the larger of either
@@ -385,8 +383,7 @@
 	 * entire decompressed kernel plus .bss and .brk sections.
 	 */
 	output = choose_random_location(input_data, input_len, output,
-					output_len > run_size ? output_len
-							      : run_size);
+					max(output_len, kernel_total_size));
 
 	/* Validate memory location choices. */
 	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))