From patchwork Thu Nov 29 23:02:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 10705493 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EF45017F0 for ; Thu, 29 Nov 2018 23:03:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E137E2B491 for ; Thu, 29 Nov 2018 23:03:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D57192B697; Thu, 29 Nov 2018 23:03:44 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8E0C92B491 for ; Thu, 29 Nov 2018 23:03:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726966AbeK3KKf (ORCPT ); Fri, 30 Nov 2018 05:10:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:44908 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726403AbeK3KKe (ORCPT ); Fri, 30 Nov 2018 05:10:34 -0500 Received: from ebiggers.mtv.corp.google.com (unknown [104.132.1.85]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 91A482146F; Thu, 29 Nov 2018 23:03:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543532606; bh=XvF/lMOC0lL0Q4e5HLcoOSHhmcyW66zlM9QPCJmkwGc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kJ6UH4llFo77x1Xs8xsh/XitHtePx9VfWwpnyfi3Hkfpn4Me4x5YHFOobgQzqs/s2 /EvxmYrqeKpdBHR++5CbxSpmhrE28tIor2YwBkz/G6W26nubptjzY8XZ5nKPKXnfGQ //B2xYA1wKEaGCtHe0HPIdmLuqsmZRzuLicGKXu8= From: Eric Biggers To: linux-crypto@vger.kernel.org Cc: Paul Crowley , Martin Willi , Milan Broz , "Jason A . Donenfeld" , linux-kernel@vger.kernel.org Subject: [PATCH v2 3/6] crypto: x86/chacha20 - limit the preemption-disabled section Date: Thu, 29 Nov 2018 15:02:14 -0800 Message-Id: <20181129230217.158038-4-ebiggers@kernel.org> X-Mailer: git-send-email 2.20.0.rc0.387.gc7a69e6b6c-goog In-Reply-To: <20181129230217.158038-1-ebiggers@kernel.org> References: <20181129230217.158038-1-ebiggers@kernel.org> MIME-Version: 1.0 Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Eric Biggers To improve responsiveness, disable preemption for each step of the walk (which is at most PAGE_SIZE) rather than for the entire encryption/decryption operation. Signed-off-by: Eric Biggers --- arch/x86/crypto/chacha20_glue.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/arch/x86/crypto/chacha20_glue.c b/arch/x86/crypto/chacha20_glue.c index 773d075a1483..036de144aab6 100644 --- a/arch/x86/crypto/chacha20_glue.c +++ b/arch/x86/crypto/chacha20_glue.c @@ -135,26 +135,24 @@ static int chacha20_simd(struct skcipher_request *req) if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) return crypto_chacha_crypt(req); - err = skcipher_walk_virt(&walk, req, true); + err = skcipher_walk_virt(&walk, req, false); crypto_chacha_init(state, ctx, walk.iv); - kernel_fpu_begin(); - while (walk.nbytes > 0) { unsigned int nbytes = walk.nbytes; if (nbytes < walk.total) nbytes = round_down(nbytes, walk.stride); + kernel_fpu_begin(); chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr, nbytes); + kernel_fpu_end(); err = skcipher_walk_done(&walk, walk.nbytes - nbytes); } - kernel_fpu_end(); - return err; }