From: "Richard W.M. Jones" Subject: [PATCH v3] crypto: Add a flag allowing the self-tests to be disabled at runtime. Date: Tue, 3 May 2016 10:00:16 +0100 Message-ID: <1462266017-28022-1-git-send-email-rjones@redhat.com> Cc: linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, corbet@lwn.net, herbert@gondor.apana.org.au, davem@davemloft.net, sm@eperm.de To: linux-kernel@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:34295 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751131AbcECJAX (ORCPT ); Tue, 3 May 2016 05:00:23 -0400 Sender: linux-crypto-owner@vger.kernel.org List-ID: v2 -> v3: - Ignore the flag if FIPS mode is enabled. v1 -> v2: - Use printk_once. Because the serial console is so slow, printing the message multiple times actually consumed about 6ms extra later on during the boot. - - - I'm trying to reduce the time taken in the kernel in initcalls, with my aim being to reduce the current ~700ms spent in initcalls before userspace, down to something like 100ms. All times on my Broadwell-U laptop, under virtualization. The purpose of this is to be able to launch VMs around containers with minimal overhead, like Intel Clear Containers, but using standard distro kernels and qemu. Currently the kernel spends 28ms (on my laptop) running crypto algorithm self-tests. Although it's possibe to disable these at compile time, Fedora kernel maintainers want to maintain a single kernel image for all uses. So this commit adds a runtime flag which callers can set to skip the self-tests in the fast container/virtualization case. Rich.