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Date: Thu, 06 Jun 2024 08:32:55 +0300
Message-Id: <D1SOT40TEXMI.A5J72PR5IWSP@kernel.org>
Subject: Re: [PATCH v14 14/14] selftests/sgx: Add scripts for EPC cgroup
 testing
From: "Jarkko Sakkinen" <jarkko@kernel.org>
To: "Haitao Huang" <haitao.huang@linux.intel.com>,
 <dave.hansen@linux.intel.com>, <kai.huang@intel.com>, <tj@kernel.org>,
 <mkoutny@suse.com>, <linux-kernel@vger.kernel.org>,
 <linux-sgx@vger.kernel.org>, <x86@kernel.org>, <cgroups@vger.kernel.org>,
 <tglx@linutronix.de>, <mingo@redhat.com>, <bp@alien8.de>, <hpa@zytor.com>,
 <sohil.mehta@intel.com>, <tim.c.chen@linux.intel.com>
Cc: <zhiquan1.li@intel.com>, <kristen@linux.intel.com>, <seanjc@google.com>,
 <zhanb@microsoft.com>, <anakrish@microsoft.com>,
 <mikko.ylinen@linux.intel.com>, <yangjie@microsoft.com>,
 <chrisyan@microsoft.com>
References: <20240531222630.4634-1-haitao.huang@linux.intel.com>
 <20240531222630.4634-15-haitao.huang@linux.intel.com>
 <D1RKK8CENNXI.1KMNDADV9C1YM@kernel.org>
 <op.2owf5xiwwjvjmi@hhuan26-mobl.amr.corp.intel.com>
In-Reply-To: <op.2owf5xiwwjvjmi@hhuan26-mobl.amr.corp.intel.com>

On Wed Jun 5, 2024 at 6:33 PM EEST, Haitao Huang wrote:

> sgx_cgroup_try_charge() expects sgx_cg_wq, so it would break unless we =
=20
> check and return 0 which was the initially implemented in v12. But then =
=20
> Kai had some concern on that we expose all the interface files to allow =
=20
> user to set limits but we don't enforce. To keep it simple we settled dow=
n =20
                                              ~~~~~~~~~~~~~~

Sure:

"Keep it simple and corpse"

> back to BUG_ON(). This would only happen rarely and user can add =20
> command-line to disable SGX if s/he really wants to start kernel in this =
=20
> case, just can't do SGX.

Even disabling all of SGX would be a less catastrophical measure.

> Yes I had a comment but Kai thought it was too obvious and I can't think =
=20
> of a better one that's not obvious so I removed:

Not great advice given. Please just document it. In patch, which
BUG_ON() I don't want to see my R-by in it, until I've reviewed an
updated version.

BR, Jarkko