| Message ID | 20190226142856.35527-1-alan.hayward@arm.com |
|---|---|
| State | New |
| Headers | show |
On Tuesday, February 26 2019, Alan Hayward wrote: > [This is a replacement for the patch "gdbserver: Add option to ignore > SO_REUSEADDR". The issue is the same, but the root cause is different]. > > When launching gdbserver, the testsuite checks for binding failure but > does not check for failure to listen to socket error (which can happen > due to another gdbserver binding to the socket at the same time). > > When this error occurs, the test will ignore the error and connect GDB > to the failed port. This may succeed and GDB will now be connected to > the gdbserver from another test. This eventually causes both tests to > fail. > > When running the tests suite with native-gdbserver across many cores, > this issue may happen once or twice, each causing random failures for > two .exp testscripts. I remember having to touch this code when I was implementing the IPv6 feature, and I think your patch makes perfect sense. It LGTM, but I'm not a global maintainer. > Example gdb.log output for the failure: > > The testsuite sucessfully notices a failure to connect to port 2348. > It launches again with port 2349, which also fails. The testsuite > ignores this error and uses gdb to connect to the port - which succeeds. > > spawn /work/build/gdb/testsuite/../gdbserver/gdbserver --once localhost:2348 /work/build/gdb/testsuite/outputs/gdb.ada/arrayidx/p^M > Can't bind address: Address already in use.^M > Exiting^M > Port 2348 is already in use. > spawn /work/build/gdb/testsuite/../gdbserver/gdbserver --once localhost:2349 /work/build/gdb/testsuite/outputs/gdb.ada/arrayidx/p^M > Can't listen on socket: Address already in use.^M > Exiting^M > target remote localhost:2349^M > Remote debugging using localhost:2349^M > Reading /lib/ld-linux-aarch64.so.1 from remote target...^M > warning: File transfers from remote targets can be slow. Use "set sysroot" to access files locally instead.^M > Reading /lib/ld-linux-aarch64.so.1 from remote target...^M > Reading symbols from target:/lib/ld-linux-aarch64.so.1...^M > Reading /lib/ld-2.23.so from remote target...^M > Reading /lib/.debug/ld-2.23.so from remote target...^M > Reading /work/build/install/lib/debug//lib/ld-2.23.so from remote target...^M > Reading /work/build/install/lib/debug/lib//ld-2.23.so from remote target...^M > Reading target:/work/build/install/lib/debug/lib//ld-2.23.so from remote target...^M > (No debugging symbols found in target:/lib/ld-linux-aarch64.so.1)^M > 0x0000ffffbf6d2cc0 in ?? () from target:/lib/ld-linux-aarch64.so.1^M > (gdb) continue^M > Continuing.^M > Reading /lib/aarch64-linux-gnu/libc.so.6 from remote target...^M > Reading /lib/aarch64-linux-gnu/libc-2.23.so from remote target...^M > Reading /lib/aarch64-linux-gnu/.debug/libc-2.23.so from remote target...^M > Reading /work/build/install/lib/debug//lib/aarch64-linux-gnu/libc-2.23.so from remote target...^M > Reading /work/build/install/lib/debug/lib/aarch64-linux-gnu//libc-2.23.so from remote target...^M > Reading target:/work/build/install/lib/debug/lib/aarch64-linux-gnu//libc-2.23.so from remote target...^M > [Inferior 1 (process 35351) exited normally]^M > (gdb) FAIL: gdb.ada/arrayidx.exp: can't run to main > > Meanwhile, at the same time, in another test, gdbserver successfully > connects to port 2349. GDB then trys to connect to the port, but it > times out because the GDB in the test above has already connected to it. > > spawn /work/build/gdb/testsuite/../gdbserver/gdbserver --once localhost:2348 /work/build/gdb/testsuite/outputs/gdb.ada/rdv_wait/foo^M > Can't bind address: Address already in use.^M > Exiting^M > Port 2348 is already in use. > spawn /work/build/gdb/testsuite/../gdbserver/gdbserver --once localhost:2349 /work/build/gdb/testsuite/outputs/gdb.ada/rdv_wait/foo^M > Process /work/build/gdb/testsuite/outputs/gdb.ada/rdv_wait/foo created; pid = 65162^M > Listening on port 2349^M > Remote debugging from host 127.0.0.1, port 45154^M > target remote localhost:2349^M > localhost:2349: Connection timed out.^M > (gdb) ^CQuit^M > (gdb) task 2^M > Cannot inspect Ada tasks when program is not running^M > > 2019-02-26 Alan Hayward <alan.hayward@arm.com> > > * lib/gdbserver-support.exp (gdbserver_start): Check for listen > failure. > --- > gdb/testsuite/lib/gdbserver-support.exp | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/gdb/testsuite/lib/gdbserver-support.exp b/gdb/testsuite/lib/gdbserver-support.exp > index 05234c43bd..dbd885aa22 100644 > --- a/gdb/testsuite/lib/gdbserver-support.exp > +++ b/gdb/testsuite/lib/gdbserver-support.exp > @@ -317,7 +317,7 @@ proc gdbserver_start { options arguments } { > -timeout 120 > -notransfer > -re "Listening on" { } > - -re "Can't bind address: Address already in use\\.\r\n" { > + -re "Can't (bind address|listen on socket): Address already in use\\.\r\n" { > verbose -log "Port $portnum is already in use." > if ![target_info exists gdb,socketport] { > # Bump the port number to avoid the conflict. > -- > 2.17.2 (Apple Git-113)
On 02/26/2019 02:28 PM, Alan Hayward wrote: > [This is a replacement for the patch "gdbserver: Add option to ignore > SO_REUSEADDR". The issue is the same, but the root cause is different]. Great, I was scratching my head over that one. > Meanwhile, at the same time, in another test, gdbserver successfully > connects to port 2349. GDB then trys to connect to the port, but it Typo: "tries" :-D Patch is OK. Thanks, Pedro Alves
diff --git a/gdb/testsuite/lib/gdbserver-support.exp b/gdb/testsuite/lib/gdbserver-support.exp index 05234c43bd..dbd885aa22 100644 --- a/gdb/testsuite/lib/gdbserver-support.exp +++ b/gdb/testsuite/lib/gdbserver-support.exp @@ -317,7 +317,7 @@ proc gdbserver_start { options arguments } { -timeout 120 -notransfer -re "Listening on" { } - -re "Can't bind address: Address already in use\\.\r\n" { + -re "Can't (bind address|listen on socket): Address already in use\\.\r\n" { verbose -log "Port $portnum is already in use." if ![target_info exists gdb,socketport] { # Bump the port number to avoid the conflict.