Commit 348aa303 authored by Andreas Schwab's avatar Andreas Schwab Committed by Benjamin Herrenschmidt
Browse files

powerpc: Align vDSO base address 



The ABI specifies a 64K alignment, we need to map the vDSO accordingly

Signed-off-by: default avatarAndreas Schwab <schwab@linux-m68k.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 7de80284

arch/powerpc/kernel/vdso.c

+10 −1
Original line number Diff line number Diff line
@@ -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