From 279ebed98bb26c3182c10a4c9340808008fbf318 Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Mon, 19 Mar 2018 10:31:54 -0400 Subject: x86/vsyscall/64: Use proper accessor to update P4D entry commit 31ad7f8e7dc94d3b85ccf9b6141ce6dfd35a1781 upstream. Writing to it directly does not work for Xen PV guests. Fixes: 49275fef986a ("x86/vsyscall/64: Explicitly set _PAGE_USER in the pagetable hierarchy") Signed-off-by: Boris Ostrovsky Signed-off-by: Thomas Gleixner Reviewed-by: Juergen Gross Acked-by: Andy Lutomirski Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180319143154.3742-1-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 577fa8adb785..542392b6aab6 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -355,7 +355,7 @@ void __init set_vsyscall_pgtable_user_bits(pgd_t *root) set_pgd(pgd, __pgd(pgd_val(*pgd) | _PAGE_USER)); p4d = p4d_offset(pgd, VSYSCALL_ADDR); #if CONFIG_PGTABLE_LEVELS >= 5 - p4d->p4d |= _PAGE_USER; + set_p4d(p4d, __p4d(p4d_val(*p4d) | _PAGE_USER)); #endif pud = pud_offset(p4d, VSYSCALL_ADDR); set_pud(pud, __pud(pud_val(*pud) | _PAGE_USER)); -- cgit v1.2.3