lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Wed,  5 Aug 2020 04:40:45 -0400
From:   Willem de Bruijn <>
        Willem de Bruijn <>,
        Colin Ian King <>
Subject: [PATCH net] selftests/net: relax cpu affinity requirement in msg_zerocopy test

From: Willem de Bruijn <>

The msg_zerocopy test pins the sender and receiver threads to separate
cores to reduce variance between runs.

But it hardcodes the cores and skips core 0, so it fails on machines
with the selected cores offline, or simply fewer cores.

The test mainly gives code coverage in automated runs. The throughput
of zerocopy ('-z') and non-zerocopy runs is logged for manual

Continue even when sched_setaffinity fails. Just log to warn anyone
interpreting the data.

Fixes: 07b65c5b31ce ("test: add msg_zerocopy test")
Reported-by: Colin Ian King <>
Signed-off-by: Willem de Bruijn <>
 tools/testing/selftests/net/msg_zerocopy.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/net/msg_zerocopy.c b/tools/testing/selftests/net/msg_zerocopy.c
index 4b02933cab8a..bdc03a2097e8 100644
--- a/tools/testing/selftests/net/msg_zerocopy.c
+++ b/tools/testing/selftests/net/msg_zerocopy.c
@@ -125,9 +125,8 @@ static int do_setcpu(int cpu)
 	CPU_SET(cpu, &mask);
 	if (sched_setaffinity(0, sizeof(mask), &mask))
-		error(1, 0, "setaffinity %d", cpu);
-	if (cfg_verbose)
+		fprintf(stderr, "cpu: unable to pin, may increase variance.\n");
+	else if (cfg_verbose)
 		fprintf(stderr, "cpu: %u\n", cpu);
 	return 0;

Powered by blists - more mailing lists