summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorBoris Ostrovsky <boris.ostrovsky@oracle.com>2018-03-19 10:31:54 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-03-28 18:23:02 +0200
commit279ebed98bb26c3182c10a4c9340808008fbf318 (patch)
tree709caa8c4b7f5024ddfab9140b439b0f01c7a55a
parent1e4ed1727e2a13f108037add6b08e2872125d19f (diff)
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 <boris.ostrovsky@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180319143154.3742-1-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/entry/vsyscall/vsyscall_64.c2
1 files changed, 1 insertions, 1 deletions
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));