From 156408c0edaacbea1137f58b28fd6ec341064310 Mon Sep 17 00:00:00 2001 From: Vishnu Pratap Singh Date: Tue, 8 Sep 2015 15:01:19 -0700 Subject: [PATCH] lib/show_mem.c: correct reserved memory calculation CMA reserved memory is not part of total reserved memory. Currently when we print the total reserve memory it considers cma as part of reserve memory and do minus of totalcma_pages from reserved, which is wrong. In cases where total reserved is less than cma reserved we will get negative values & while printing we print as unsigned and we will get a very large value. Below is the show mem output on X86 ubuntu based system where CMA reserved is 100MB (25600 pages) & total reserved is ~40MB(10316 pages). And reserve memory shows a large value because of this bug. Before: [ 127.066430] 898908 pages RAM [ 127.066432] 671682 pages HighMem/MovableOnly [ 127.066434] 4294952012 pages reserved [ 127.066436] 25600 pages cma reserved After: [ 44.663129] 898908 pages RAM [ 44.663130] 671682 pages HighMem/MovableOnly [ 44.663130] 10316 pages reserved [ 44.663131] 25600 pages cma reserved Signed-off-by: Vishnu Pratap Singh Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Joonsoo Kim Cc: Laurent Pinchart Cc: Sasha Levin Cc: Danesh Petigara Cc: Laura Abbott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/show_mem.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/lib/show_mem.c b/lib/show_mem.c index adc98e1825ba..1feed6a2b12a 100644 --- a/lib/show_mem.c +++ b/lib/show_mem.c @@ -38,11 +38,9 @@ void show_mem(unsigned int filter) printk("%lu pages RAM\n", total); printk("%lu pages HighMem/MovableOnly\n", highmem); -#ifdef CONFIG_CMA - printk("%lu pages reserved\n", (reserved - totalcma_pages)); - printk("%lu pages cma reserved\n", totalcma_pages); -#else printk("%lu pages reserved\n", reserved); +#ifdef CONFIG_CMA + printk("%lu pages cma reserved\n", totalcma_pages); #endif #ifdef CONFIG_QUICKLIST printk("%lu pages in pagetable cache\n",