From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id E131445DB9 for ; Wed, 27 Nov 2024 18:22:00 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id DD91E402E4; Wed, 27 Nov 2024 18:22:00 +0100 (CET) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mails.dpdk.org (Postfix) with ESMTP id EF8F84066C for ; Wed, 27 Nov 2024 18:21:58 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1732728118; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=S+o6ZHxqlRqpYH/Cfmg486uVvZu6AAhNoIj4jDATmZk=; b=N0MRr1MAUvuVz61XocI1cMqablAWtrHYC8ie3+HpoQPP89sqaCMt/HdXen+nxv4YCelEJN rSrXUtND9x6BnLH4LCgPx4XAUvzYOtPchLPBvZlNhT3wAjHB2wPMwrBiKRns5kcG+UVgQF gUQElf8Sbeg2MfCpJwlzny0bpz2rYMo= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-175-vo5xOGAMNtesih7wQj7Ojg-1; Wed, 27 Nov 2024 12:21:54 -0500 X-MC-Unique: vo5xOGAMNtesih7wQj7Ojg-1 X-Mimecast-MFC-AGG-ID: vo5xOGAMNtesih7wQj7Ojg Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (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 mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 99FE61956095; Wed, 27 Nov 2024 17:21:53 +0000 (UTC) Received: from rh.redhat.com (unknown [10.39.192.52]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 75AA0300019E; Wed, 27 Nov 2024 17:21:52 +0000 (UTC) From: Kevin Traynor To: Vladimir Medvedkin Cc: dpdk stable Subject: patch 'hash: fix thash LFSR initialization' has been queued to stable release 21.11.9 Date: Wed, 27 Nov 2024 17:18:14 +0000 Message-ID: <20241127171916.690404-67-ktraynor@redhat.com> In-Reply-To: <20241127171916.690404-1-ktraynor@redhat.com> References: <20241127171916.690404-1-ktraynor@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: L5UC7AJRmdGaPRPWeez7qJN_Qvj-xp8faYSFWBX4lbI_1732728113 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true X-BeenThere: stable@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: patches for DPDK stable branches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: stable-bounces@dpdk.org Hi, FYI, your patch has been queued to stable release 21.11.9 Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet. It will be pushed if I get no objections before 12/02/24. So please shout if anyone has objections. Also note that after the patch there's a diff of the upstream commit vs the patch applied to the branch. This will indicate if there was any rebasing needed to apply to the stable branch. If there were code changes for rebasing (ie: not only metadata diffs), please double check that the rebase was correctly done. Queued patches are on a temporary branch at: https://github.com/kevintraynor/dpdk-stable This queued commit can be viewed at: https://github.com/kevintraynor/dpdk-stable/commit/23128ef43fd91441d18b8a4651964c4a75e7b4d4 Thanks. Kevin --- >From 23128ef43fd91441d18b8a4651964c4a75e7b4d4 Mon Sep 17 00:00:00 2001 From: Vladimir Medvedkin Date: Fri, 6 Sep 2024 17:01:41 +0000 Subject: [PATCH] hash: fix thash LFSR initialization [ upstream commit ebf7f1188ea83d6154746e90d535392113ecb1e8 ] Reverse polynomial for an LFSR was initialized improperly which could generate improper bit sequence in some situations. This patch implements proper polynomial reversing function. Fixes: 28ebff11c2dc ("hash: add predictable RSS") Signed-off-by: Vladimir Medvedkin --- lib/hash/rte_thash.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/lib/hash/rte_thash.c b/lib/hash/rte_thash.c index 2b97482cfb..c14e594914 100644 --- a/lib/hash/rte_thash.c +++ b/lib/hash/rte_thash.c @@ -162,4 +162,28 @@ thash_get_rand_poly(uint32_t poly_degree) } +static inline uint32_t +get_rev_poly(uint32_t poly, int degree) +{ + int i; + /* + * The implicit highest coefficient of the polynomial + * becomes the lowest after reversal. + */ + uint32_t rev_poly = 1; + uint32_t mask = (1 << degree) - 1; + + /* + * Here we assume "poly" argument is an irreducible polynomial, + * thus the lowest coefficient of the "poly" must always be equal to "1". + * After the reversal, this the lowest coefficient becomes the highest and + * it is omitted since the highest coefficient is implicitly determined by + * degree of the polynomial. + */ + for (i = 1; i < degree; i++) + rev_poly |= ((poly >> i) & 0x1) << (degree - i); + + return rev_poly & mask; +} + static struct thash_lfsr * alloc_lfsr(struct rte_thash_ctx *ctx) @@ -181,5 +205,5 @@ alloc_lfsr(struct rte_thash_ctx *ctx) } while (lfsr->state == 0); /* init reverse order polynomial */ - lfsr->rev_poly = (lfsr->poly >> 1) | (1 << (lfsr->deg - 1)); + lfsr->rev_poly = get_rev_poly(lfsr->poly, lfsr->deg); /* init proper rev_state*/ lfsr->rev_state = lfsr->state; -- 2.47.0 --- Diff of the applied patch vs upstream commit (please double-check if non-empty: --- --- - 2024-11-27 17:17:40.378398637 +0000 +++ 0067-hash-fix-thash-LFSR-initialization.patch 2024-11-27 17:17:38.260269554 +0000 @@ -1 +1 @@ -From ebf7f1188ea83d6154746e90d535392113ecb1e8 Mon Sep 17 00:00:00 2001 +From 23128ef43fd91441d18b8a4651964c4a75e7b4d4 Mon Sep 17 00:00:00 2001 @@ -5,0 +6,2 @@ +[ upstream commit ebf7f1188ea83d6154746e90d535392113ecb1e8 ] + @@ -11 +12,0 @@ -Cc: stable@dpdk.org @@ -19 +20 @@ -index 10721effe6..99a685f0c8 100644 +index 2b97482cfb..c14e594914 100644 @@ -22 +23 @@ -@@ -167,4 +167,28 @@ thash_get_rand_poly(uint32_t poly_degree) +@@ -162,4 +162,28 @@ thash_get_rand_poly(uint32_t poly_degree) @@ -51 +52 @@ -@@ -186,5 +210,5 @@ alloc_lfsr(struct rte_thash_ctx *ctx) +@@ -181,5 +205,5 @@ alloc_lfsr(struct rte_thash_ctx *ctx)