From: Mark Wielaard <mjw@redhat.com>
Date: Fri, 9 Jul 2010 22:26:37 +0000 (+0200)
Subject: Fix usymbols.exp test for 32-on-64 (again). PR11722.
X-Git-Tag: release-1.3~52
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=6bc671114948b95f6eafaf62790f5a4a7c3ab350;p=systemtap.git

Fix usymbols.exp test for 32-on-64 (again). PR11722.

Bug introduced by commit 82ea0c. Add a comment why we need the same
"chopping" of addr in both _stp_umod_lookup and _stp_kallsyms_lookup.

* runtime/sym.c (_stp_kallsyms_lookup): Detect long used as 32bit address.
---

diff --git a/runtime/sym.c b/runtime/sym.c
index db58181bc..895ec8c4d 100644
--- a/runtime/sym.c
+++ b/runtime/sym.c
@@ -163,6 +163,13 @@ static const char *_stp_kallsyms_lookup(unsigned long addr,
 	  {
 	    unsigned long vm_start = 0;
 	    unsigned long vm_end = 0;
+#ifdef CONFIG_COMPAT
+        /* Handle 32bit signed values in 64bit longs, chop off top bits.
+           _stp_umod_lookup does the same, but we need it here for the
+           binary search on addr below. */
+        if (test_tsk_thread_flag(task, TIF_32BIT))
+          addr &= ((compat_ulong_t) ~0);
+#endif
 	    m = _stp_umod_lookup(addr, task, modname, &vm_start, &vm_end);
 	    if (m)
 	      {