From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 415D5C4332F for ; Wed, 12 Oct 2022 22:04:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229715AbiJLWEg (ORCPT ); Wed, 12 Oct 2022 18:04:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229816AbiJLWDo (ORCPT ); Wed, 12 Oct 2022 18:03:44 -0400 Received: from mx0b-002e3701.pphosted.com (mx0b-002e3701.pphosted.com [148.163.143.35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC1F912C8A3; Wed, 12 Oct 2022 15:01:20 -0700 (PDT) Received: from pps.filterd (m0134423.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 29CKwflC006339; Wed, 12 Oct 2022 21:59:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hpe.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pps0720; bh=pkIjY3xNYdD7u0iVrBec5NLvLKLYByXvLSfeEAPzOWA=; b=H/+AVupIA0qT3WW+ZAU2dM2Gj2l3wqwR0WsAa/VfsVsS5iNMLJC7y8Ht8zY9f5OvhkBx 2yLbpwmj37y7COimS4bcYZXap7tWfA+f9jfIliFcbQ+513C5zXVqoqpMPMUKpaQZdv18 hktdM2YGYo3tRFTVAi7YV1xAMWnSW89cLVpbAz4A923DrH/GUDNRl5Ld07SqTiP+PXvj VO8N9e4AHFDwKfHaVK05G3rZ6EdQ3Am7Xvyz8NwOIvIN/3DX0mQtHBM0ONsISnk24f22 +trjHtXOEgf2mx27hfc02CqJehN6CTaOKRtBmoBwWIjCo4twBOe4dR3MxIan4xh9zojX PQ== Received: from p1lg14880.it.hpe.com (p1lg14880.it.hpe.com [16.230.97.201]) by mx0b-002e3701.pphosted.com (PPS) with ESMTPS id 3k653c8da7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 12 Oct 2022 21:59:50 +0000 Received: from p1lg14885.dc01.its.hpecorp.net (unknown [10.119.18.236]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by p1lg14880.it.hpe.com (Postfix) with ESMTPS id 8611C806B5C; Wed, 12 Oct 2022 21:59:49 +0000 (UTC) Received: from adevxp033-sys.us.rdlabs.hpecorp.net (unknown [16.231.227.36]) by p1lg14885.dc01.its.hpecorp.net (Postfix) with ESMTP id 28602808ECE; Wed, 12 Oct 2022 21:59:49 +0000 (UTC) From: Robert Elliott To: herbert@gondor.apana.org.au, davem@davemloft.net, tim.c.chen@linux.intel.com, ap420073@gmail.com, ardb@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Robert Elliott Subject: [PATCH v2 04/19] crypto: x86/sha - limit FPU preemption Date: Wed, 12 Oct 2022 16:59:16 -0500 Message-Id: <20221012215931.3896-5-elliott@hpe.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221012215931.3896-1-elliott@hpe.com> References: <20221006223151.22159-1-elliott@hpe.com> <20221012215931.3896-1-elliott@hpe.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-GUID: Uwyq1NOSShnQQpJzF5T27vXCpBPm0wlx X-Proofpoint-ORIG-GUID: Uwyq1NOSShnQQpJzF5T27vXCpBPm0wlx X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-10-12_11,2022-10-12_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 lowpriorityscore=0 clxscore=1015 impostorscore=0 mlxscore=0 spamscore=0 mlxlogscore=999 adultscore=0 bulkscore=0 priorityscore=1501 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2210120138 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As done by the ECB and CBC helpers in arch/x86/crypt/ecb_cbc_helpers.h, limit the number of bytes processed between kernel_fpu_begin() and kernel_fpu_end() calls. Those functions call preempt_disable() and preempt_enable(), so the CPU core is unavailable for scheduling while running. This leads to "rcu_preempt detected expedited stalls" with stack dumps pointing to the optimized hash function if the module is loaded and used a lot: rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: ... For example, that can occur during boot with the stack track pointing to the sha512-x86 function if the system set to use SHA-512 for module signing. The call trace includes: module_sig_check mod_verify_sig pkcs7_verify pkcs7_digest sha512_finup sha512_base_do_update Fixes: 66be89515888 ("crypto: sha1 - SSSE3 based SHA1 implementation for x86-64") Fixes: 8275d1aa6422 ("crypto: sha256 - Create module providing optimized SHA256 routines using SSSE3, AVX or AVX2 instructions.") Fixes: 87de4579f92d ("crypto: sha512 - Create module providing optimized SHA512 routines using SSSE3, AVX or AVX2 instructions.") Fixes: aa031b8f702e ("crypto: x86/sha512 - load based on CPU features") Suggested-by: Herbert Xu Reviewed-by: Tim Chen Signed-off-by: Robert Elliott --- arch/x86/crypto/sha1_ssse3_glue.c | 32 ++++++++++++++++++++++++----- arch/x86/crypto/sha256_ssse3_glue.c | 32 ++++++++++++++++++++++++----- arch/x86/crypto/sha512_ssse3_glue.c | 32 ++++++++++++++++++++++++----- 3 files changed, 81 insertions(+), 15 deletions(-) diff --git a/arch/x86/crypto/sha1_ssse3_glue.c b/arch/x86/crypto/sha1_ssse3_glue.c index 44340a1139e0..a9f5779b41ca 100644 --- a/arch/x86/crypto/sha1_ssse3_glue.c +++ b/arch/x86/crypto/sha1_ssse3_glue.c @@ -26,6 +26,8 @@ #include #include +#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */ + static int sha1_update(struct shash_desc *desc, const u8 *data, unsigned int len, sha1_block_fn *sha1_xform) { @@ -41,9 +43,18 @@ static int sha1_update(struct shash_desc *desc, const u8 *data, */ BUILD_BUG_ON(offsetof(struct sha1_state, state) != 0); - kernel_fpu_begin(); - sha1_base_do_update(desc, data, len, sha1_xform); - kernel_fpu_end(); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha1_base_do_update(desc, data, chunk, sha1_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); return 0; } @@ -54,9 +65,20 @@ static int sha1_finup(struct shash_desc *desc, const u8 *data, if (!crypto_simd_usable()) return crypto_sha1_finup(desc, data, len, out); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha1_base_do_update(desc, data, chunk, sha1_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); + kernel_fpu_begin(); - if (len) - sha1_base_do_update(desc, data, len, sha1_xform); sha1_base_do_finalize(desc, sha1_xform); kernel_fpu_end(); diff --git a/arch/x86/crypto/sha256_ssse3_glue.c b/arch/x86/crypto/sha256_ssse3_glue.c index 3a5f6be7dbba..322c8aa907af 100644 --- a/arch/x86/crypto/sha256_ssse3_glue.c +++ b/arch/x86/crypto/sha256_ssse3_glue.c @@ -40,6 +40,8 @@ #include #include +#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */ + asmlinkage void sha256_transform_ssse3(struct sha256_state *state, const u8 *data, int blocks); @@ -58,9 +60,18 @@ static int _sha256_update(struct shash_desc *desc, const u8 *data, */ BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0); - kernel_fpu_begin(); - sha256_base_do_update(desc, data, len, sha256_xform); - kernel_fpu_end(); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha256_base_do_update(desc, data, chunk, sha256_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); return 0; } @@ -71,9 +82,20 @@ static int sha256_finup(struct shash_desc *desc, const u8 *data, if (!crypto_simd_usable()) return crypto_sha256_finup(desc, data, len, out); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha256_base_do_update(desc, data, chunk, sha256_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); + kernel_fpu_begin(); - if (len) - sha256_base_do_update(desc, data, len, sha256_xform); sha256_base_do_finalize(desc, sha256_xform); kernel_fpu_end(); diff --git a/arch/x86/crypto/sha512_ssse3_glue.c b/arch/x86/crypto/sha512_ssse3_glue.c index 6d3b85e53d0e..fd5075a32613 100644 --- a/arch/x86/crypto/sha512_ssse3_glue.c +++ b/arch/x86/crypto/sha512_ssse3_glue.c @@ -39,6 +39,8 @@ #include #include +#define FPU_BYTES 4096U /* avoid kernel_fpu_begin/end scheduler/rcu stalls */ + asmlinkage void sha512_transform_ssse3(struct sha512_state *state, const u8 *data, int blocks); @@ -57,9 +59,18 @@ static int sha512_update(struct shash_desc *desc, const u8 *data, */ BUILD_BUG_ON(offsetof(struct sha512_state, state) != 0); - kernel_fpu_begin(); - sha512_base_do_update(desc, data, len, sha512_xform); - kernel_fpu_end(); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha512_base_do_update(desc, data, chunk, sha512_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); return 0; } @@ -70,9 +81,20 @@ static int sha512_finup(struct shash_desc *desc, const u8 *data, if (!crypto_simd_usable()) return crypto_sha512_finup(desc, data, len, out); + do { + unsigned int chunk = min(len, FPU_BYTES); + + if (chunk) { + kernel_fpu_begin(); + sha512_base_do_update(desc, data, chunk, sha512_xform); + kernel_fpu_end(); + } + + len -= chunk; + data += chunk; + } while (len); + kernel_fpu_begin(); - if (len) - sha512_base_do_update(desc, data, len, sha512_xform); sha512_base_do_finalize(desc, sha512_xform); kernel_fpu_end(); -- 2.37.3