Re: [PATCH v1 3/9] powerpc/vdso: don't clear PG_reserved
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2018-12-17 11:38:49
Also in:
linux-arm-kernel, linux-mediatek, linux-mm, linux-riscv, linux-s390, lkml
David Hildenbrand [off-list ref] 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 <redacted> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Christophe Leroy <redacted> Cc: Kees Cook <redacted> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: David Hildenbrand <redacted> --- arch/powerpc/kernel/vdso.c | 2 -- 1 file changed, 2 deletions(-)
Thanks. Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) cheers
quoted hunk ↗ jump to hunk
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