|
From: <sv...@va...> - 2011-06-15 21:35:46
|
Author: sewardj
Date: 2011-06-15 22:30:55 +0100 (Wed, 15 Jun 2011)
New Revision: 11818
Log:
Fix safe_fd exhaustion in fork chain caused by non closing of shared_mem_fd
Patch that fixes the problem reported by Christian Borntraeger.
The problem was created by keeping the shared memory mapped file opened
without reason till the process does an exec.
In case of a chain of forked processes (without exec), the range of safe_fd
reserved for Valgrind own usage becomes exhausted.
* coregrind/m_gdbserver/remote-utils.c :
do not VG_(safe_fd) shared_mem_fd (as it is now closed directly)
close shared_mem_fd once file is mmap-ed and written.
* gdbserver_tests/nlfork_chain.stderr.exp,nlfork_chain.vgtest,
fork_chain.c,nlfork_chain.stdout.exp:
new files
* gdbserver_tests/Makefile.am:
modified for new nlfork_chain test
(patch from #214909 c 103,
Philippe Waroquiers, phi...@sk...)
Added:
trunk/gdbserver_tests/fork_chain.c
trunk/gdbserver_tests/nlfork_chain.stderr.exp
trunk/gdbserver_tests/nlfork_chain.stdout.exp
trunk/gdbserver_tests/nlfork_chain.vgtest
Modified:
trunk/coregrind/m_gdbserver/remote-utils.c
trunk/gdbserver_tests/Makefile.am
Modified: trunk/coregrind/m_gdbserver/remote-utils.c
===================================================================
--- trunk/coregrind/m_gdbserver/remote-utils.c 2011-06-15 19:07:26 UTC (rev 11817)
+++ trunk/coregrind/m_gdbserver/remote-utils.c 2011-06-15 21:30:55 UTC (rev 11818)
@@ -279,10 +279,6 @@
fatal("error writing %d bytes to shared mem %s\n",
(int) sizeof(VgdbShared), shared_mem);
}
- shared_mem_fd = VG_(safe_fd)(shared_mem_fd);
- if (shared_mem_fd == -1) {
- fatal("safe_fd for vgdb shared_mem %s failed\n", shared_mem);
- }
{
SysRes res = VG_(am_shared_mmap_file_float_valgrind)
(sizeof(VgdbShared), VKI_PROT_READ|VKI_PROT_WRITE,
@@ -295,6 +291,7 @@
addr_shared = sr_Res (res);
}
shared = (VgdbShared*) addr_shared;
+ VG_(close) (shared_mem_fd);
}
/* we open the read side FIFO in non blocking mode
Modified: trunk/gdbserver_tests/Makefile.am
===================================================================
--- trunk/gdbserver_tests/Makefile.am 2011-06-15 19:07:26 UTC (rev 11817)
+++ trunk/gdbserver_tests/Makefile.am 2011-06-15 21:30:55 UTC (rev 11818)
@@ -72,10 +72,14 @@
nlcontrolc.stderr.exp \
nlcontrolc.stdinB.gdb \
nlcontrolc.stdoutB.exp \
- nlcontrolc.vgtest
+ nlcontrolc.vgtest \
+ nlfork_chain.stderr.exp \
+ nlfork_chain.stdout.exp \
+ nlfork_chain.vgtest
check_PROGRAMS = \
clean_after_fork \
+ fork_chain \
sleepers \
t \
watchpoints
Added: trunk/gdbserver_tests/fork_chain.c
===================================================================
--- trunk/gdbserver_tests/fork_chain.c (rev 0)
+++ trunk/gdbserver_tests/fork_chain.c 2011-06-15 21:30:55 UTC (rev 11818)
@@ -0,0 +1,37 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/wait.h>
+void fork_chain(int level)
+{
+ int pid;
+
+ printf ("forking level %d\n", level);
+ fflush (stdout);
+ pid = fork();
+ if (pid == -1) {
+ perror("fork");
+ exit(1);
+ }
+
+ if (pid == 0) {
+ if (level > 0) {
+ fork_chain (level - 1);
+ }
+ } else {
+ int ret;
+ int status;
+ while((ret = waitpid(pid, &status, 0)) != pid) {
+ if (errno != EINTR) {
+ perror("waitpid");
+ exit(1);
+ }
+ }
+ }
+}
+int main()
+{
+ fork_chain (20);
+ return 0;
+}
Added: trunk/gdbserver_tests/nlfork_chain.stderr.exp
===================================================================
--- trunk/gdbserver_tests/nlfork_chain.stderr.exp (rev 0)
+++ trunk/gdbserver_tests/nlfork_chain.stderr.exp 2011-06-15 21:30:55 UTC (rev 11818)
@@ -0,0 +1,24 @@
+Nulgrind, the minimal Valgrind tool
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
Added: trunk/gdbserver_tests/nlfork_chain.stdout.exp
===================================================================
--- trunk/gdbserver_tests/nlfork_chain.stdout.exp (rev 0)
+++ trunk/gdbserver_tests/nlfork_chain.stdout.exp 2011-06-15 21:30:55 UTC (rev 11818)
@@ -0,0 +1,21 @@
+forking level 20
+forking level 19
+forking level 18
+forking level 17
+forking level 16
+forking level 15
+forking level 14
+forking level 13
+forking level 12
+forking level 11
+forking level 10
+forking level 9
+forking level 8
+forking level 7
+forking level 6
+forking level 5
+forking level 4
+forking level 3
+forking level 2
+forking level 1
+forking level 0
Added: trunk/gdbserver_tests/nlfork_chain.vgtest
===================================================================
--- trunk/gdbserver_tests/nlfork_chain.vgtest (rev 0)
+++ trunk/gdbserver_tests/nlfork_chain.vgtest 2011-06-15 21:30:55 UTC (rev 11818)
@@ -0,0 +1,4 @@
+# test that gdbserver properly cleans up its resources in a chain
+# of forked processes.
+prog: fork_chain
+vgopts: --tool=none --vgdb=yes --trace-children=yes --vgdb-prefix=./vgdb-prefix-nlfork_chain
|