mm: enhance free_reserved_area() to support poisoning memory with zero

Address more review comments from last round of code review.
1) Enhance free_reserved_area() to support poisoning freed memory with
   pattern '0'. This could be used to get rid of poison_init_mem()
   on ARM64.
2) A previous patch has disabled memory poison for initmem on s390
   by mistake, so restore to the original behavior.
3) Remove redundant PAGE_ALIGN() when calling free_reserved_area().

Signed-off-by: Jiang Liu <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: David Howells <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Cc: Jianguo Wu <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Kamezawa Hiroyuki <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Michel Lespinasse <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Tang Chen <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Wen Congyang <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yasuaki Ishimatsu <[email protected]>
Cc: Yinghai Lu <[email protected]>
Cc: Russell King <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 4 insertions, 4 deletions

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 7fae391caf86..2070651c1bb4 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -601,7 +601,7 @@ void __init mem_init(void)
 
 #ifdef CONFIG_SA1111
 	/* now that our DMA memory is actually so designated, we can free it */
-	free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, 0, NULL);
+	free_reserved_area(__va(PHYS_PFN_OFFSET), swapper_pg_dir, -1, NULL);
 #endif
 
 	free_highpages();
@@ -729,12 +729,12 @@ void free_initmem(void)
 	extern char __tcm_start, __tcm_end;
 
 	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
-	free_reserved_area(&__tcm_start, &__tcm_end, 0, "TCM link");
+	free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
 #endif
 
 	poison_init_mem(__init_begin, __init_end - __init_begin);
 	if (!machine_is_integrator() && !machine_is_cintegrator())
-		free_initmem_default(0);
+		free_initmem_default(-1);
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -745,7 +745,7 @@ void free_initrd_mem(unsigned long start, unsigned long end)
 {
 	if (!keep_initrd) {
 		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
-		free_reserved_area((void *)start, (void *)end, 0, "initrd");
+		free_reserved_area((void *)start, (void *)end, -1, "initrd");
 	}
 }