From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cyril Hrubis Date: Tue, 3 Sep 2019 10:58:14 +0200 Subject: [LTP] [PATCH v4 0/4] Basic eBPF tests In-Reply-To: <494040796.9629252.1567489841971.JavaMail.zimbra@redhat.com> References: <20190826111024.19053-1-chrubis@suse.cz> <1492475067.8173800.1566829761941.JavaMail.zimbra@redhat.com> <20190902145524.GB10860@rei.lan> <494040796.9629252.1567489841971.JavaMail.zimbra@redhat.com> Message-ID: <20190903085814.GA23372@rei.lan> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Hi! > > > There's one EPERM I can reproduce reliably with bpf_map test, which appears > > > to originate from "bpf_charge_memlock". > > > > > > There's a deferred component to map freeing, and unchange appears to be > > > part of it: > > > bpf_map_release > > > bpf_map_put > > > INIT_WORK(&map->work, bpf_map_free_deferred); > > > (deferred) bpf_uncharge_memlock > > > > > > When I lower max locked memory, it's easy to hit: > > > # ulimit -l 128; ./bpf_map01 -i 100 > > > ... > > > bpf_map01.c:52: CONF: bpf() requires CAP_SYS_ADMIN on this system: EPERM > > > > > > Can you try bumping max locked memory to some high value and check > > > if that helps your case? > > > > Looks like this was the case, with high enough value the tests works > > without a problem. The question is if and/or what should be done about > > this... > > We can try asking on bpf@vger.kernel.org, if they see it as bug. Let's start with this, it would be a bit nicer if it returned EAGAIN instead of EPERM at least. Will you send the email or should I? > I'd push tests with a comment. Or setup() that bumps the limit: whatever > current limit is, add 2MB to it, so single/few iteration(s) should always work. Let's go with a comment for now, we can add code later on once we are clear on what is the expected outcome. -- Cyril Hrubis chrubis@suse.cz