[PATCH] xen: remove global bit from __default_kernel_pte_mask for pv guests

From: Juergen Gross
Date: Mon Jul 02 2018 - 06:00:28 EST


When removing the global bit from __supported_pte_mask do the same for
__default_kernel_pte_mask in order to avoid the WARN_ONCE() in
check_pgprot() when setting a kernel pte before having called
init_mem_mapping().

Cc: <stable@xxxxxxxxxxxxxxx> # 4.17
Reported-by: Michael Young <m.a.young@xxxxxxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
arch/x86/xen/enlighten_pv.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 0f4cd9e5bed4..cf7b13d3e911 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1230,6 +1230,7 @@ asmlinkage __visible void __init xen_start_kernel(void)

/* Prevent unwanted bits from being set in PTEs. */
__supported_pte_mask &= ~_PAGE_GLOBAL;
+ __default_kernel_pte_mask &= ~_PAGE_GLOBAL;

/*
* Prevent page tables from being allocated in highmem, even
--
2.13.7