Subject: [PATCH RFC 3/7] powerpc/vdso: don't clear PG_reserved

From: David Hildenbrand <[email-masked]>
Date: Wed, 5 Dec 2018 13:28:47 +0100

The VDSO is part of the kernel image and therefore the struct pages are
marked as reserved during boot.

As we install a special mapping, the actual struct pages will never be
exposed to MM via the page tables. We can therefore leave the pages
marked as reserved.

Cc: Benjamin Herrenschmidt <[email-masked]>
Cc: Paul Mackerras <[email-masked]>
Cc: Michael Ellerman <[email-masked]>
Cc: Christophe Leroy <[email-masked]>
Cc: Kees Cook <[email-masked]>
Cc: Andrew Morton <[email-masked]>
Cc: Michal Hocko <[email-masked]>
Cc: Matthew Wilcox <[email-masked]>
Signed-off-by: David Hildenbrand <[email-masked]>
---
 arch/powerpc/kernel/vdso.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 65b3bdb99f0b..d59dc2e9a695 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -795,7 +795,6 @@ static int __init vdso_init(void)
 	BUG_ON(vdso32_pagelist == NULL);
 	for (i = 0; i < vdso32_pages; i++) {
 		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
-		ClearPageReserved(pg);
 		get_page(pg);
 		vdso32_pagelist[i] = pg;
 	}
@@ -809,7 +808,6 @@ static int __init vdso_init(void)
 	BUG_ON(vdso64_pagelist == NULL);
 	for (i = 0; i < vdso64_pages; i++) {
 		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
-		ClearPageReserved(pg);
 		get_page(pg);
 		vdso64_pagelist[i] = pg;
 	}
-- 
2.17.2