[tip:x86/boot] x86/xen: Supply RSDP address in boot params for PVH guests

[tip-bot for Juergen Gross <tipbot@zytor.com>]

Commit-ID:  930ba49b2ce7b09a5eddc21385fd944ba6b4e829
Gitweb:     https://git.kernel.org/tip/930ba49b2ce7b09a5eddc21385fd944ba6b4e829
Author:     Juergen Gross <jgross@suse.com>
AuthorDate: Fri, 8 Dec 2017 16:11:39 +0100
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Mon, 11 Dec 2017 15:14:21 +0100

x86/xen: Supply RSDP address in boot params for PVH guests

When booted via the special PVH entry save the RSDP address set in the
boot information block in struct boot_params. This will enable Xen to
locate the RSDP at an arbitrary address.

Signed-off-by: Juergen Gross <jgross@suse.com>
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: corbet@lwn.net
Cc: lenb@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: rjw@rjwysocki.net
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20171208151139.30213-5-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/xen/enlighten_pvh.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index 6e6430c..e85e6da 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -68,9 +68,12 @@ 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).
+	 * The RSDP address is available from version 2.14 on.
 	 */
-	pvh_bootparams.hdr.version = (2 << 8) | 12;
+	pvh_bootparams.hdr.version = (2 << 8) | 14;
 	pvh_bootparams.hdr.type_of_loader = (9 << 4) | 0; /* Xen loader */
+
+	pvh_bootparams.hdr.acpi_rsdp_addr = pvh_start_info.rsdp_paddr;
 }
 
 /*