Dmitry,
Thank you for the details!
I have a couple of comments so far.
+ if (word[5][0] == '[') {
+ // not a shared library entry. ignore.
+ if (strncmp(word[5],"[stack",6) == 0) {
+ continue;
+ }
+ if (strncmp(word[5],"[heap]",6) == 0) {
+ continue;
+ }
+
+ // SA don't handle VDSO
+ if (strncmp(word[5],"[vdso]",6) == 0) {
+ continue;
+ }
+ if (strncmp(word[5],"[vsyscall]",6) == 0) {
+ continue;
+ }
+ }
I'd suggest to simplify the fragment above to something like thus:
+ // SA does not handle the lines with patterns:
+ // "[stack]", "[heap]", "[vdso]","[vsyscall]", etc.
+ if (word[5][0] == '[') {
+ continue;// not a shared library entry, ignore
+ }
This fragment does not look correct:
+ if (nwords > 6) {
+ // prelink altered mapfile when the program is running.
+ // Entries like one below have to be skipped
+ // /lib64/libc-2.15.so (deleted)
+ // SO name in entries like one below have to be stripped.
+ // /lib64/libpthread-2.15.so.#prelink#.EECVts
+ char *s = strstr(word[5],".#prelink#");
+ if (s == NULL) {
+ // No prelink keyword. skip deleted library
+ print_debug("skip shared object %s deleted by prelink\n", word[5]);
+ continue;
+ }
+
+ // Fall through
+ print_debug("rectifing shared object name %s changed by prelink\n",
word[5]);
+ *s = 0;
+ }
The line with the pattern "(deleted)" has 7 words, but the line like:
<addr> /lib64/libpthread-2.15.so.#prelink#.EECVts
has only 6 words, and so, your code will not process it properly.
I'd expect something like this:
+ if (nwords > 6) {
+ // prelink altered mapfile when the program is running.
+ // Entries like one below have to be skipped:
+ // /lib64/libc-2.15.so (deleted)
+ print_debug("skip shared object %s deleted by prelink\n", word[5]);
+ continue;
+ } else {
+ char *s = strstr(word[5],".#prelink#");
+ if (s != NULL) {
+ // There is the prelink keyword
+ print_debug("rectifying shared object name %s changed by prelink\n",
word[5]);
+ *s = 0;
+ }
+ }
Is it hard to add a unit test for this issue?
Thanks,
Serguei
On 6/12/14 3:10 AM, Dmitry Samersoff wrote:
Serguei,
*The problem:*
If someone run prelink utility while Java program is running DSO's
mappings in it's /proc/<pid>/maps become messy.
After prelink it contains entry like
<addr> /lib64/libc-2.15.so (deleted)
<addr> /lib64/libpthread-2.15.so.#prelink#.EECVts
instead of normal
<addr> /lib64/libc-2.15.so
Here is the letter from Carlos, describing the problem in details:
https://bugs.openjdk.java.net/browse/JDK-8038392
*The fix:*
The fix allows SA to handle situation above.
Also I fix longstanding issue - maps file parser in SA doesn't skip
[stack*, [heap] etc entry and attempts to open it as a DSO
*Testing:*
I tested it manually with a different of prelink options (no prelink,
prelink all, prelink some libraries only)
-Dmitry
On 2014-06-12 13:50, serguei.spit...@oracle.com wrote:
Hi Dmitry,
There is no description of the fix.
Could you, please, provide one?
What did you basically wanted to achieve?
Also, how did the fix been tested?
It seems, a unit test would be nice to have.
Thanks,
Serguei
On 6/5/14 12:08 AM, Dmitry Samersoff wrote:
http://cr.openjdk.java.net/~dsamersoff/JDK-8038392/webrev.02/
On 2014-05-20 17:47, Dmitry Samersoff wrote:
On 2014-04-07 16:56, Dmitry Samersoff wrote:
Hi Everybody,
Please review the patch
http://cr.openjdk.java.net/~dsamersoff/JDK-8038392/webrev.02/
it's based on the patch contributed by Carlos Santos (see CR) and all
credentials belong to him.
-Dmitry
