x86/xen: Fix boot loader version reported for PVH guests

The boot loader version reported via sysfs is wrong in case of the
kernel being booted via the Xen PVH boot entry. it should be 2.12
(0x020c), but it is reported to be 2.18 (0x0212).

As the current way to set the version is error prone use the more
readable variant (2 << 8) | 12.

Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 4.12
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boris.ostrovsky@oracle.com
Cc: bp@alien8.de
Cc: corbet@lwn.net
Cc: linux-doc@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181010061456.22238-2-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index c85d1a88f47693232369411588cfc19084086b25..f7f77023288ab3e614d96fcb7c1b2e413bde9436 100644 (file)
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -75,7 +75,7 @@ static void __init init_pvh_bootparams(void)
         * Version 2.12 supports Xen entry point but we will use default x86/PC
         * environment (i.e. hardware_subarch 0).
         */
-       pvh_bootparams.hdr.version = 0x212;
+       pvh_bootparams.hdr.version = (2 << 8) | 12;
        pvh_bootparams.hdr.type_of_loader = (9 << 4) | 0; /* Xen loader */
 
        x86_init.acpi.get_root_pointer = pvh_get_root_pointer;