@@ -587,6 +587,12 @@ static void xen_p4d_walk(struct mm_struct *mm, p4d_t *p4d,
xen_pud_walk(mm, pud, func, last, limit);
}
+#ifdef CONFIG_X86_VSYSCALL_EMULATION
+#define __KERNEL_MAP_TOP (VSYSCALL_ADDR + PAGE_SIZE)
+#else
+#define __KERNEL_MAP_TOP FIXADDR_TOP
+#endif
+
/*
* (Yet another) pagetable walker. This one is intended for pinning a
* pagetable. This means that it walks a pagetable and calls the
@@ -594,7 +600,7 @@ static void xen_p4d_walk(struct mm_struct *mm, p4d_t *p4d,
* at every level. It walks the entire pagetable, but it only bothers
* pinning pte pages which are below limit. In the normal case this
* will be STACK_TOP_MAX, but at boot we need to pin up to
- * FIXADDR_TOP.
+ * __KERNEL_MAP_TOP.
*
* We must skip the Xen hole in the middle of the address space, just after
* the big x86-64 virtual hole.
@@ -609,7 +615,7 @@ static void __xen_pgd_walk(struct mm_struct *mm, pgd_t *pgd,
/* The limit is the last byte to be touched */
limit--;
- BUG_ON(limit >= FIXADDR_TOP);
+ BUG_ON(limit >= __KERNEL_MAP_TOP);
/*
* 64-bit has a great big hole in the middle of the address
@@ -797,7 +803,7 @@ static void __init xen_after_bootmem(void)
#ifdef CONFIG_X86_VSYSCALL_EMULATION
SetPagePinned(virt_to_page(level3_user_vsyscall));
#endif
- xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP);
+ xen_pgd_walk(&init_mm, xen_mark_pinned, __KERNEL_MAP_TOP);
}
static void xen_unpin_page(struct mm_struct *mm, struct page *page,
If vsyscall page is moved out of fixmap area, then FIXADDR_TOP would be below vsyscall page. So it should pin up to VSYSCALL_ADDR if vsyscall is enabled. Suggested-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com> Cc: Thomas Garnier <thgarnie@chromium.org> Cc: Kees Cook <keescook@chromium.org> --- arch/x86/xen/mmu_pv.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)