From: Juergen Gross <jgross@suse.com>
Date: Mon, 2 Jul 2018 10:00:18 +0000 (+0200)
Subject: xen: remove global bit from __default_kernel_pte_mask for pv guests
X-Git-Tag: v4.19~613^2~1
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e69b5d308da72cbf4e7911c3979f9a46d28532af;p=platform%2Fkernel%2Flinux-rpi3.git

xen: remove global bit from __default_kernel_pte_mask for pv guests

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@vger.kernel.org> # 4.17
Reported-by: Michael Young <m.a.young@durham.ac.uk>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 8d4e2e1..4816b6f 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1229,6 +1229,7 @@ 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