From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tommi Rantala Date: Wed, 30 Jan 2019 17:00:47 +0200 Subject: [LTP] [PATCH] syscalls/setrlimit03.c: read /proc/sys/fs/nr_open for RLIMIT_NOFILE limit Message-ID: <20190130150047.26307-1-tt.rantala@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it From: Tommi Rantala Since kernel v2.6.25 RLIMIT_NOFILE limit is no longer hardcoded to NR_OPEN, but can be set via /proc/sys/fs/nr_open, see kernel commit 9cfe015aa424b3c003baba3841a60dd9b5ad319b ("get rid of NR_OPEN and introduce a sysctl_nr_open"). nr_open default value is 1024*1024, so setrlimit03 has been passing fine on new kernels, only "unexpectedly succeeding" if nr_open is set to some larger value. Signed-off-by: Tommi Rantala --- testcases/kernel/syscalls/setrlimit/setrlimit03.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/testcases/kernel/syscalls/setrlimit/setrlimit03.c b/testcases/kernel/syscalls/setrlimit/setrlimit03.c index 29b52aa7f..643432bb4 100644 --- a/testcases/kernel/syscalls/setrlimit/setrlimit03.c +++ b/testcases/kernel/syscalls/setrlimit/setrlimit03.c @@ -36,6 +36,7 @@ #endif static struct rlimit rlim1, rlim2; +static unsigned int nr_open; static struct tcase { struct rlimit *rlimt; @@ -51,7 +52,10 @@ static void verify_setrlimit(unsigned int n) TEST(setrlimit(RLIMIT_NOFILE, tc->rlimt)); if (TST_RET != -1) { - tst_res(TFAIL, "call succeeded unexpectedly"); + tst_res(TFAIL, "call succeeded unexpectedly " + "(nr_open=%u rlim_cur=%lu rlim_max=%lu)", nr_open, + (unsigned long)(tc->rlimt->rlim_cur), + (unsigned long)(tc->rlimt->rlim_max)); return; } @@ -65,10 +69,16 @@ static void verify_setrlimit(unsigned int n) static void setup(void) { + if (tst_kvercmp(2, 6, 25) < 0) { + nr_open = NR_OPEN; + } else { + SAFE_FILE_SCANF("/proc/sys/fs/nr_open", "%u", &nr_open); + } + SAFE_GETRLIMIT(RLIMIT_NOFILE, &rlim1); rlim2.rlim_max = rlim1.rlim_cur; rlim2.rlim_cur = rlim1.rlim_max + 1; - rlim1.rlim_max = NR_OPEN + 1; + rlim1.rlim_max = nr_open + 1; } static struct tst_test test = { -- 2.19.2