From 348aa3030096e61474a5537fed5bd69e70b755c0 Mon Sep 17 00:00:00 2001 From: Andreas Schwab Date: Sun, 4 Oct 2009 02:35:41 +0000 Subject: powerpc: Align vDSO base address The ABI specifies a 64K alignment, we need to map the vDSO accordingly Signed-off-by: Andreas Schwab Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/vdso.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c index 94e2df3cae07..137dc22afa42 100644 --- a/arch/powerpc/kernel/vdso.c +++ b/arch/powerpc/kernel/vdso.c @@ -50,6 +50,9 @@ /* Max supported size for symbol names */ #define MAX_SYMNAME 64 +/* The alignment of the vDSO */ +#define VDSO_ALIGNMENT (1 << 16) + extern char vdso32_start, vdso32_end; static void *vdso32_kbase = &vdso32_start; static unsigned int vdso32_pages; @@ -231,15 +234,21 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) * pick a base address for the vDSO in process space. We try to put it * at vdso_base which is the "natural" base for it, but we might fail * and end up putting it elsewhere. + * Add enough to the size so that the result can be aligned. */ down_write(&mm->mmap_sem); vdso_base = get_unmapped_area(NULL, vdso_base, - vdso_pages << PAGE_SHIFT, 0, 0); + (vdso_pages << PAGE_SHIFT) + + ((VDSO_ALIGNMENT - 1) & PAGE_MASK), + 0, 0); if (IS_ERR_VALUE(vdso_base)) { rc = vdso_base; goto fail_mmapsem; } + /* Add required alignment. */ + vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT); + /* * Put vDSO base into mm struct. We need to do this before calling * install_special_mapping or the perf counter mmap tracking code -- cgit v1.2.2