[OE-core] [PATCH v2 1/1] qemu: add wrapper for qemu-mips binary

[Laurentiu Palcu]

qemu-mips user emulation binary segfaults when running any kind of
binary. This is due to a MMU access fault in the virtual CPU. This
problem has been introduced in qemu when 4GB of vmem were reserved for
32-on-64 bit.

This workaround will need to be reverted once the proper fix is found.

[YOCTO #3143]

Signed-off-by: Laurentiu Palcu <laurentiu.palcu at intel.com>
---
 meta/recipes-devtools/qemu/qemu_1.2.0.bb |   16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/meta/recipes-devtools/qemu/qemu_1.2.0.bb b/meta/recipes-devtools/qemu/qemu_1.2.0.bb
index 191ee48..fa53e57 100644
--- a/meta/recipes-devtools/qemu/qemu_1.2.0.bb
+++ b/meta/recipes-devtools/qemu/qemu_1.2.0.bb
@@ -17,7 +17,7 @@ SRC_URI = "\
 SRC_URI[md5sum] = "78eb1e984f4532aa9f2bdd3c127b5b61"
 SRC_URI[sha256sum] = "c8b84420d9f4869397f84cad2dabd9a475b7723d619a924a873740353e9df936"
 
-PR = "r2"
+PR = "r3"
 
 SRC_URI_append_virtclass-nativesdk = "\
     file://relocatable_sdk.patch \
@@ -29,6 +29,20 @@ do_configure_prepend_virtclass-nativesdk() {
 		sed -i 's/-lX11//g' Makefile.target
 	fi
 }
+
+# The following fragment will create a wrapper for qemu-mips user emulation
+# binary in order to work around a segmentation fault issue. Basically, by
+# default, the reserved virtual address space for 32-on-64 bit is set to 4GB.
+# This will trigger a MMU access fault in the virtual CPU. With this change,
+# the qemu-mips works fine.
+# IMPORTANT: This piece needs to be removed once the root cause is fixed!
+inherit utils
+do_install_append() {
+	create_wrapper ${D}/${bindir}/qemu-mips \
+		QEMU_RESERVED_VA=0x0
+}
+# END of qemu-mips workaround
+
 do_configure_prepend_virtclass-native() {
 	# Undo the -lX11 added by linker-flags.patch, don't assume that host has libX11 installed
 	sed -i 's/-lX11//g' Makefile.target
-- 
1.7.9.5