systemtap: support --sysroot option in variety of situations in cross build

For details on issues fixed please look at commit message of individual
patches.

Upstream-Status: Backport [systemtap@sourceware.org]
(From OE-Core rev: 5aa93de3a79c8691e74e982d3d4b0099b04f5555)

Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/meta/recipes-kernel/systemtap/systemtap/0001-sysroot-fix-short-release-r-option-handling.patch b/meta/recipes-kernel/systemtap/systemtap/0001-sysroot-fix-short-release-r-option-handling.patch
new file mode 100644
index 0000000000..b31d6274e2
--- /dev/null
+++ b/meta/recipes-kernel/systemtap/systemtap/0001-sysroot-fix-short-release-r-option-handling.patch
@@ -0,0 +1,53 @@
+From a9ce89bcd2d78728faef59bda60e75510972cd56 Mon Sep 17 00:00:00 2001
+From: Victor Kamensky <kamensky@cisco.com>
+Date: Wed, 14 Mar 2018 17:09:44 -0500
+Subject: [PATCH] sysroot: fix short release -r option handling
+
+* setupdwfl.cxx (debuginfo_path_insert_sysroot): Add a '/' to the end of
+  the sysroot for path_insert_sysroot().
+  (setup_dwfl_kernel): Simplify logic when finding the kernel path to send
+  to elfutils.
+
+Upstream-Status: Backport
+Signed-off-by: Victor Kamensky <kamensky@cisco.com>
+---
+ setupdwfl.cxx | 19 ++++++++++++-------
+ 1 file changed, 12 insertions(+), 7 deletions(-)
+
+diff --git a/setupdwfl.cxx b/setupdwfl.cxx
+index 2a87982..f6c3157 100644
+--- a/setupdwfl.cxx
++++ b/setupdwfl.cxx
+@@ -339,6 +339,13 @@ static char * path_insert_sysroot(string sysroot, string path)
+ 
+ void debuginfo_path_insert_sysroot(string sysroot)
+ {
++  // FIXME: This is a short-term fix, until we expect sysroot paths to
++  // always end with a '/' (and never be empty).
++  //
++  // The path_insert_sysroot() function assumes that sysroot has a '/'
++  // on the end. Make sure that is true.
++  if (sysroot.back() != '/')
++    sysroot.push_back('/');
+   debuginfo_path = path_insert_sysroot(sysroot, debuginfo_path);
+   debuginfo_usr_path = path_insert_sysroot(sysroot, debuginfo_usr_path);
+ }
+@@ -358,13 +365,11 @@ setup_dwfl_kernel (unsigned *modules_found, systemtap_session &s)
+   // no way to set the dwfl_callback.debuginfo_path and always
+   // passs the plain kernel_release here.  So instead we have to
+   // hard-code this magic here.
+-   string lib_path = "/lib/modules/" + s.kernel_release + "/build";
+-   if (s.kernel_build_tree == string(s.sysroot + lib_path) ||
+-       (s.kernel_build_tree == lib_path
+-       && s.sysroot == "/"))
+-      elfutils_kernel_path = s.kernel_release;
+-   else
+-      elfutils_kernel_path = s.kernel_build_tree;
++  string lib_path = s.sysroot + "/lib/modules/" + s.kernel_release + "/build";
++  if (s.kernel_build_tree == lib_path)
++    elfutils_kernel_path = s.kernel_release;
++  else
++    elfutils_kernel_path = s.kernel_build_tree;
+   offline_modules_found = 0;
+ 
+   // First try to report full path modules.