From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out01.mta.xmission.com (out01.mta.xmission.com [166.70.13.231]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1C9917F for ; Tue, 29 Jun 2021 15:29:00 +0000 (UTC) Received: from in02.mta.xmission.com ([166.70.13.52]) by out01.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lyFIN-008dtP-NA; Tue, 29 Jun 2021 09:05:03 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95]:58984 helo=email.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lyFIM-001WCn-AL; Tue, 29 Jun 2021 09:05:03 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds Cc: Alexey Gladkov , Linux Kernel Mailing List , Linux Containers References: <87fsx1vcr9.fsf@disp2133> Date: Tue, 29 Jun 2021 10:04:19 -0500 In-Reply-To: (Linus Torvalds's message of "Mon, 28 Jun 2021 20:47:12 -0700") Message-ID: <87r1gku2z0.fsf@disp2133> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) Precedence: bulk X-Mailing-List: containers@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1lyFIM-001WCn-AL;;;mid=<87r1gku2z0.fsf@disp2133>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX192t3ZGKJh38+xv4Fmewi8hlGXzg4wt6Nc= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: ** X-Spam-Status: No, score=2.8 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TM2_M_HEADER_IN_MSG,XMSubLong,XMSubMetaSxObfu_03, XMSubMetaSx_00 autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.4997] * 0.7 XMSubLong Long Subject * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 1397; Body=1 Fuz1=1 Fuz2=1] * 1.0 XMSubMetaSx_00 1+ Sexy Words * 1.2 XMSubMetaSxObfu_03 Obfuscated Sexy Noun-People X-Spam-DCC: XMission; sa07 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: **;Linus Torvalds X-Spam-Relay-Country: X-Spam-Timing: total 689 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 12 (1.8%), b_tie_ro: 11 (1.6%), parse: 1.24 (0.2%), extract_message_metadata: 20 (2.9%), get_uri_detail_list: 2.2 (0.3%), tests_pri_-1000: 15 (2.1%), tests_pri_-950: 1.15 (0.2%), tests_pri_-900: 1.04 (0.2%), tests_pri_-90: 307 (44.6%), check_bayes: 296 (43.0%), b_tokenize: 6 (0.8%), b_tok_get_all: 102 (14.8%), b_comp_prob: 3.4 (0.5%), b_tok_touch_all: 182 (26.4%), b_finish: 0.92 (0.1%), tests_pri_0: 315 (45.8%), check_dkim_signature: 0.50 (0.1%), check_dkim_adsp: 2.7 (0.4%), poll_dns_idle: 0.55 (0.1%), tests_pri_10: 3.3 (0.5%), tests_pri_500: 9 (1.3%), rewrite_mail: 0.00 (0.0%) Subject: Re: [GIT PULL] ucounts: Count rlimits in each user namespace X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Linus Torvalds writes: > On Mon, Jun 28, 2021 at 3:35 PM Eric W. Biederman wrote: >> >> This is the work mainly by Alexey Gladkov to limit rlimits to the >> rlimits of the user that created a user namespace, and to allow users to >> have stricter limits on the resources created within a user namespace. > > I guess all the performance issues got sorted, since I haven't seen > any reports from the test robots. Yes. The structure was made to not change anything unnecessarily (such as the ordering in sigqueue_alloc) and the performances differences went away. With the code in linux-next the entire cycle I think that is a reliable result. There are probably some things we could do to further optimize things but we did not need them to avoid regressions. > I do end up with two questions, mainly because of looking at the > result of the conflict resolution. > > In particular, in __sigqueue_alloc(), two oddities.. > > Why the "sigpending < LONG_MAX" test in that > > if (override_rlimit || (sigpending < LONG_MAX && sigpending <= > task_rlimit(t, RLIMIT_SIGPENDING))) { > > thing? > And why test for "ucounts" being non-NULL in > > if (ucounts && dec_rlimit_ucounts(ucounts, > UCOUNT_RLIMIT_SIGPENDING, 1)) > put_ucounts(ucounts); > > when afaik both of those should be happy with a NULL 'ucounts' pointer > (if it was NULL, we certainly already used it for the reverse > operations for get_ucounts() and inc_rlimit_ucounts()..) > > Hmm? Yes. I suspect that those tests are left over from a previous version of the change. Alex do you remember why those tests are there? > And somebody should verify that I didn't screw anything up in my merge > resolution. It all looked very straightforward, but mistakes happen.. Just reading through the resolution looks correct. Eric