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

jgross1 · Ingo Molnar · commit 357d291ce035 · 2018-10-10T10:44:21.000+02:00
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
@@ -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;
