diff mbox series

[v1,3/9] powerpc/vdso: don't clear PG_reserved

Message ID 20181214111014.15672-4-david@redhat.com (mailing list archive)
State New, archived
Headers show
Series [v1,1/9] agp: efficeon: no need to set PG_reserved on GATT tables | expand

Commit Message

David Hildenbrand Dec. 14, 2018, 11:10 a.m. UTC
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 <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
 arch/powerpc/kernel/vdso.c | 2 --
 1 file changed, 2 deletions(-)

Comments

Michael Ellerman Dec. 17, 2018, 11:38 a.m. UTC | #1
David Hildenbrand <david@redhat.com> writes:

> 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 <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Michal Hocko <mhocko@kernel.org>
> Cc: Matthew Wilcox <willy@infradead.org>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  arch/powerpc/kernel/vdso.c | 2 --
>  1 file changed, 2 deletions(-)

Thanks.

Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

cheers

> 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
diff mbox series

Patch

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;
 	}