From: roland <roland>
Date: Wed, 20 Feb 2008 02:44:10 +0000 (+0000)
Subject: 2008-02-19  Roland McGrath  <roland@redhat.com>
X-Git-Tag: release-0.6.2~45
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=f9331b2988dce35aa72bd92fa69ecda45066211b;p=systemtap.git

2008-02-19  Roland McGrath  <roland@redhat.com>

	* tapsets.cxx (query_module): Use dwfl_module_getdwarf rather
	than dwfl_module_getelf for e_machine check.
	(dwarf_query::get_blacklist_section): Likewise for section search.
	Ignore non-SHF_ALLOC sections.
---

diff --git a/tapsets.cxx b/tapsets.cxx
index 52a75e59f..2f24129ce 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -2615,10 +2615,15 @@ dwarf_query::blacklisted_p(const string& funcname,
 
 string dwarf_query::get_blacklist_section(Dwarf_Addr addr)
 {
-       Dwarf_Addr baseaddr;
        string blacklist_section;
-       Elf* elf = dwfl_module_getelf (dw.module, & baseaddr);
-       Dwarf_Addr offset = addr - baseaddr;
+       Dwarf_Addr bias;
+       // We prefer dwfl_module_getdwarf to dwfl_module_getelf here,
+       // because dwfl_module_getelf can force costly section relocations
+       // we don't really need, while either will do for this purpose.
+       Elf* elf = (dwarf_getelf (dwfl_module_getdwarf (dw.module, &bias))
+		   ?: dwfl_module_getelf (dw.module, &bias));
+
+       Dwarf_Addr offset = addr - bias;
        if (elf)
         {
           Elf_Scn* scn = 0;
@@ -2630,6 +2635,9 @@ string dwarf_query::get_blacklist_section(Dwarf_Addr addr)
               GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
               if (! shdr) continue; // XXX error?
 
+	      if (!(shdr->sh_flags & SHF_ALLOC))
+		continue;
+
               GElf_Addr start = shdr->sh_addr;
               GElf_Addr end = start + shdr->sh_size;
               if (! (offset >= start && offset < end))