From: Jan Beulich <jbeulich@suse.com>
Date: Mon, 7 Sep 2020 08:34:03 +0000 (+0200)
Subject: Revert "x86: generalize padding field handling"
X-Git-Tag: archive/raspbian/4.16.0+51-g0941d6cb-1+rpi1~2^2~42^2~1696
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=e52716154da04967f9b9d7cf9a1655ea4bcd9e93;p=xen.git

Revert "x86: generalize padding field handling"

This reverts commit 696c273f3d9a169911308fb7e0a702a3eb6a150d.

I was based on the flase assumption that padding fields need no
copying: If native code checks such fields, they of course need
copying in. And if the ABI specifies them to be zero on
completion, we also need to copy them out.
---

diff --git a/xen/common/compat/memory.c b/xen/common/compat/memory.c
index 215b8f52d6..3851f756c7 100644
--- a/xen/common/compat/memory.c
+++ b/xen/common/compat/memory.c
@@ -354,13 +354,10 @@ int compat_memory_op(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) compat)
                 return -EFAULT;
 
 #define XLAT_vnuma_topology_info_HNDL_vdistance_h(_d_, _s_)		\
-            case XLAT_vnuma_topology_info_vdistance_pad:                \
             guest_from_compat_handle((_d_)->vdistance.h, (_s_)->vdistance.h)
 #define XLAT_vnuma_topology_info_HNDL_vcpu_to_vnode_h(_d_, _s_)		\
-            case XLAT_vnuma_topology_info_vcpu_to_vnode_pad:            \
             guest_from_compat_handle((_d_)->vcpu_to_vnode.h, (_s_)->vcpu_to_vnode.h)
 #define XLAT_vnuma_topology_info_HNDL_vmemrange_h(_d_, _s_)		\
-            case XLAT_vnuma_topology_info_vmemrange_pad:                \
             guest_from_compat_handle((_d_)->vmemrange.h, (_s_)->vmemrange.h)
 
             XLAT_vnuma_topology_info(nat.vnuma, &cmp.vnuma);
diff --git a/xen/tools/get-fields.sh b/xen/tools/get-fields.sh
index 753e37eb2e..002db2093f 100644
--- a/xen/tools/get-fields.sh
+++ b/xen/tools/get-fields.sh
@@ -218,7 +218,7 @@ for line in sys.stdin.readlines():
 				fi
 				;;
 			[\,\;])
-				if [ $level = 2 -a -n "$(echo $id | $SED 's,_\?pad[[:digit:]]*,,')" ]
+				if [ $level = 2 -a -n "$(echo $id | $SED 's,^_pad[[:digit:]]*,,')" ]
 				then
 					if [ $kind = union ]
 					then
@@ -347,7 +347,7 @@ build_body ()
 			fi
 			;;
 		[\,\;])
-			if [ $level = 2 -a -n "$(echo $id | $SED 's,_\?pad[[:digit:]]*,,')" ]
+			if [ $level = 2 -a -n "$(echo $id | $SED 's,^_pad[[:digit:]]*,,')" ]
 			then
 				if [ -z "$array" -a -z "$array_type" ]
 				then
@@ -437,7 +437,7 @@ check_field ()
 				id=$token
 				;;
 			[\,\;])
-				if [ $level = 2 -a -n "$(echo $id | $SED 's,_\?pad[[:digit:]]*,,')" ]
+				if [ $level = 2 -a -n "$(echo $id | $SED 's,^_pad[[:digit:]]*,,')" ]
 				then
 					check_field $1 $2 $3.$id "$fields"
 					test "$token" != ";" || fields= id=
@@ -491,7 +491,7 @@ build_check ()
 			test $level != 2 -o $arrlvl != 1 || id=$token
 			;;
 		[\,\;])
-			if [ $level = 2 -a -n "$(echo $id | $SED 's,_\?pad[[:digit:]]*,,')" ]
+			if [ $level = 2 -a -n "$(echo $id | $SED 's,^_pad[[:digit:]]*,,')" ]
 			then
 				check_field $kind $1 $id "$fields"
 				test "$token" != ";" || fields= id=