sysutils/xen-tools: fix build with clang 13.0.0

Sponsored by: Citrix Systems R&D
Approved by: bapt (implicit)

2 files changed, 109 insertions, 1 deletions

diff --git a/sysutils/xen-tools/Makefile b/sysutils/xen-tools/Makefile
index 64dcddc10a7d..1d2d3ec85c42 100644
--- a/sysutils/xen-tools/Makefile
+++ b/sysutils/xen-tools/Makefile
@@ -1,7 +1,7 @@
 PORTNAME=	xen
 PKGNAMESUFFIX=	-tools
 PORTVERSION=	4.15.0
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	sysutils emulators
 MASTER_SITES=	http://downloads.xenproject.org/release/xen/${PORTVERSION}/
 
@@ -59,6 +59,9 @@ DOCS_ALL_TARGET=	docs
 INSTALL_TARGET=		install-tools
 DOCS_INSTALL_TARGET=	install-docs
 
+# Fix pv shim build with clang 13.0.0
+EXTRA_PATCHES+=	${PATCHDIR}/0001-efi-fix-alignment-of-function-parameters-in-compat-m.patch:-p1
+
 .include <bsd.port.options.mk>
 
 .if ${OPSYS} != FreeBSD
diff --git a/sysutils/xen-tools/files/0001-efi-fix-alignment-of-function-parameters-in-compat-m.patch b/sysutils/xen-tools/files/0001-efi-fix-alignment-of-function-parameters-in-compat-m.patch
new file mode 100644
index 000000000000..1612c5a113a1
--- /dev/null
+++ b/sysutils/xen-tools/files/0001-efi-fix-alignment-of-function-parameters-in-compat-m.patch
@@ -0,0 +1,105 @@
+From be12fcca8b784e456df3adedbffe657d753c5ff9 Mon Sep 17 00:00:00 2001
+From: Roger Pau Monne <roger.pau@citrix.com>
+Date: Thu, 18 Nov 2021 09:28:06 +0100
+Subject: [PATCH] efi: fix alignment of function parameters in compat mode
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Currently the max_store_size, remain_store_size and max_size in
+compat_pf_efi_runtime_call are 4 byte aligned, which makes clang
+13.0.0 complain with:
+
+In file included from compat.c:30:
+./runtime.c:646:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 2 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
+            &op->u.query_variable_info.max_store_size,
+            ^
+./runtime.c:647:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 3 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
+            &op->u.query_variable_info.remain_store_size,
+            ^
+./runtime.c:648:13: error: passing 4-byte aligned argument to 8-byte aligned parameter 4 of 'QueryVariableInfo' may result in an unaligned pointer access [-Werror,-Walign-mismatch]
+            &op->u.query_variable_info.max_size);
+            ^
+Fix this by bouncing the variables on the stack in order for them to
+be 8 byte aligned.
+
+Note this could be done in a more selective manner to only apply to
+compat code calls, but given the overhead of making an EFI call doing
+an extra copy of 3 variables doesn't seem to warrant the special
+casing.
+
+Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
+Release-Acked-by: Ian Jackson <iwj@xenproject.org>
+Reviewed-by: Ian Jackson <iwj@xenproject.org>
+Signed-off-by: Ian Jackson <iwj@xenproject.org>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+
+---
+Changes since v3:
+ - Remove hard tabs.  Apply Jan's r-b as authorised in email.
+Changes since v2:
+ - Adjust the commentary as per discussion.
+Changes since v1:
+ - Copy back the results.
+---
+ xen/common/efi/runtime.c | 31 +++++++++++++++++++++++++++----
+ 1 file changed, 27 insertions(+), 4 deletions(-)
+
+diff --git a/xen/common/efi/runtime.c b/xen/common/efi/runtime.c
+index 375b94229e..d2fdc28df3 100644
+--- a/xen/common/efi/runtime.c
++++ b/xen/common/efi/runtime.c
+@@ -607,6 +607,9 @@ int efi_runtime_call(struct xenpf_efi_runtime_call *op)
+     break;
+ 
+     case XEN_EFI_query_variable_info:
++    {
++        uint64_t max_store_size, remain_store_size, max_size;
++
+         if ( op->misc & ~XEN_EFI_VARINFO_BOOT_SNAPSHOT )
+             return -EINVAL;
+ 
+@@ -638,16 +641,36 @@ int efi_runtime_call(struct xenpf_efi_runtime_call *op)
+ 
+         if ( !efi_enabled(EFI_RS) || (efi_rs->Hdr.Revision >> 16) < 2 )
+             return -EOPNOTSUPP;
++
++        /*
++         * Bounce the variables onto the stack to make them 8 byte aligned when
++         * called from the compat handler, as their placement in
++         * compat_pf_efi_runtime_call will make them 4 byte aligned instead and
++         * and compilers may validly complain.
++         *
++         * Note that while the function parameters are OUT only, copy the
++         * values here anyway just in case. This is done regardless of whether
++         * called from the compat handler or not, as it's not worth the extra
++         * logic to differentiate.
++         */
++        max_store_size = op->u.query_variable_info.max_store_size;
++        remain_store_size = op->u.query_variable_info.remain_store_size;
++        max_size = op->u.query_variable_info.max_size;
++
+         state = efi_rs_enter();
+         if ( !state.cr3 )
+             return -EOPNOTSUPP;
+         status = efi_rs->QueryVariableInfo(
+-            op->u.query_variable_info.attr,
+-            &op->u.query_variable_info.max_store_size,
+-            &op->u.query_variable_info.remain_store_size,
+-            &op->u.query_variable_info.max_size);
++            op->u.query_variable_info.attr, &max_store_size, &remain_store_size,
++            &max_size);
+         efi_rs_leave(&state);
++
++        op->u.query_variable_info.max_store_size = max_store_size;
++        op->u.query_variable_info.remain_store_size = remain_store_size;
++        op->u.query_variable_info.max_size = max_size;
++
+         break;
++    }
+ 
+     case XEN_EFI_query_capsule_capabilities:
+     case XEN_EFI_update_capsule:
+-- 
+2.33.0
+