[ovs-dev] [patch v3 1/4] conntrack: Stop exporting internal datastructures.

[Ben Pfaff]

On Mon, Dec 10, 2018 at 07:18:43PM -0800, Darrell Ball wrote:
> On Mon, Dec 10, 2018 at 5:22 PM Ben Pfaff <blp at ovn.org> wrote:
> 
> > On Mon, Dec 10, 2018 at 03:47:17PM -0800, Ben Pfaff wrote:
> > > On Sun, Dec 02, 2018 at 09:17:16PM -0800, Darrell Ball wrote:
> > > > Remove the exporting of the main internal conntrack datastructure.
> > > > These are made static.  Also stop passing around a pointer parameter
> > > > to all the internal datastructures; only one or two is used
> > > > for a given code path and these can be referenced directly and passed
> > > > specifically where appropriate.
> > > >
> > > > Signed-off-by: Darrell Ball <dlu998 at gmail.com>
> > >
> > > Seems fine, I applied this to master.  Thank you!
> >
> > Actually I had to un-apply this because:
> >
> > 1099: dpctl - add-dp del-dp                           FAILED (
> > ovs-macros.at:193)
> > 1100: dpctl - add-if set-if del-if                    FAILED (
> > ovs-macros.at:193)
> >
> > due to the following Address Sanitizer reports.  The following is for
> > 1099 but the one for 1100 is almost identical:
> >
> > =================================================================
> > ==17824==ERROR: AddressSanitizer: SEGV on unknown address 0xeafffba8 (pc
> > 0xf657d67d bp 0x00000000 sp 0xffc65150 T0)
> > ==17824==The signal is caused by a READ memory access.
> >     #0 0xf657d67c in __GI___pthread_timedjoin_ex
> > (/lib/i386-linux-gnu/libpthread.so.0+0x767c)
> >     #1 0xf657d5c3 in pthread_join
> > (/lib/i386-linux-gnu/libpthread.so.0+0x75c3)
> >     #2 0xf7522c24 in conntrack_destroy ../lib/conntrack.c:378
> >
> 
> 
> I don't see this using the address sanitizer; I am using
> 
> *../configure** CFLAGS="-g -O2 **-march=native**  -fsanitize=address
> -fno-omit-frame-pointer -fno-common" **--with-linux=/lib/modules/`uname
> -r`/build CC=gcc **--enable-Werror*
> 
> Furthermore, I don't see a functional change here, but I'll double check.

When I apply the following patch:

diff --git a/lib/conntrack.c b/lib/conntrack.c
index a69026d6f32f..f9bdfb6c2aa3 100644
--- a/lib/conntrack.c
+++ b/lib/conntrack.c
@@ -338,6 +338,7 @@ ct_print_conn_info(const struct conn *c, const char *log_msg,
 void
 conntrack_init(void)
 {
+    VLOG_WARN("%s:%d", __FILE__, __LINE__);
     long long now = time_msec();
 
     ct_rwlock_init(&resources_lock);
@@ -374,6 +375,7 @@ conntrack_init(void)
 void
 conntrack_destroy(void)
 {
+    VLOG_WARN("%s:%d", __FILE__, __LINE__);
     latch_set(&clean_thread_exit);
     pthread_join(clean_thread, NULL);
     latch_destroy(&clean_thread_exit);

The test shows the following logging:

--- /dev/null   2018-11-19 11:45:05.360009223 -0800
+++ /home/blp/nicira/ovs/_build/tests/testsuite.dir/at-groups/1099/stdout       2018-12-11 08:50:04.623158278 -0800
@@ -0,0 +1,3 @@
+2018-12-11T16:50:04.582Z|00008|conntrack|WARN|../lib/conntrack.c:341
+2018-12-11T16:50:04.596Z|00031|conntrack|WARN|../lib/conntrack.c:341
+2018-12-11T16:50:04.613Z|00038|conntrack|WARN|../lib/conntrack.c:378

which indicates that conntrack_init() is being called more than once.