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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8952CE63CA4 for ; Sun, 25 Jan 2026 21:28:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=v5CVp6AAdxPRS7c1qysAYvNHT2y3oHzixFhgdmCPVjg=; b=2UeYmaVrmCgwtdgE8NAhvAfHhq QSkLXlfg6X2Et83vY33tlNOYsb2e3+5SnfUdQ7TdKFUxPgolczmY5WuCj/SjjNqIQhSLNO5/Q8GLn YYYjWHHmUz0vraskYiv1igQvKjP36Rb8LMmrFkwfCAdcBwYrp6TBtglb1yVLPjCzgOXi3u4rhEERM 7PcBiJ/hDkrF2lgOAKdYYjhyr7UHI6kZInR3/MKfyjaGdysx8ak33/lzGAk1vlWTe0tgHG0mZQraf Aozt6V9czA+Z8HaKA/m418e2IX4izjGFg529wRtCY4w4BhFMltp/zHHaAKTipXHn6mEPSqklktJjU ukpX9aeg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vk7ed-0000000BWw1-2L1t; Sun, 25 Jan 2026 21:28:19 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vk7eY-0000000BWvW-3CId; Sun, 25 Jan 2026 21:28:18 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 736ED409EC; Sun, 25 Jan 2026 21:28:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D110AC4CEF1; Sun, 25 Jan 2026 21:28:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769376493; bh=uVMCMyvfZ4s9lS2txgigny86OJMSLMjE2gP+cqhj00c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j1pq3GN6k3TjxjrXyfJ5SbFrdJy+8dWn7dNf97tdLKx9L4Or+d4TQMG8yZn62iS++ hqYJPu45/ukXIuVqOnFmedqx1R+mwpjOCeDsQHgptMv8S/cHZ4iwHVVya/sWSKtOaZ g5bhOSaxgze/EAqu3mSytqDTxl3pSr6z91HRyWzWqwpgdS9z7im1liYaY8AfZlY0WG S0eGbVOVpemE6s8EMI1lR9XE43e0R5tBqVaFPHvmq/bv9fc+ZVFPvMBkQtjLjHBMQX FKp67dFV0Zk1nIUXWzwZ4xG1Xyf/hm/cOYO8Hn2mMut4zkd4nYkbWXSdcMpLJFLTqA p6swMaUAabx1w== From: Jakub Kicinski To: mmyangfl@gmail.com Cc: Jakub Kicinski , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, pabeni@redhat.com, lorenzo@kernel.org, andrew+netdev@lunn.ch, netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com, linux-kernel@vger.kernel.org Subject: Re: [net-next] net: airoha: Use u64_stats_t with u64_stats_sync properly Date: Sun, 25 Jan 2026 13:28:05 -0800 Message-ID: <20260125212805.3374863-1-kuba@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260122185255.2761568-1-mmyangfl@gmail.com> References: <20260122185255.2761568-1-mmyangfl@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260125_132814_820793_0F2CBDE6 X-CRM114-Status: GOOD ( 10.32 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This is an AI-generated review of your patch. 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For local reproduction steps see https://netdev-ai.bots.linux.dev/ai-local.html --- net: airoha: Use u64_stats_t with u64_stats_sync properly This commit converts statistics fields from u64 to u64_stats_t and changes direct arithmetic operations to u64_stats_add()/u64_stats_read() calls to ensure atomic operations on 64-bit architectures. > diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c > index 62bcbbbe2a95..6ed220e5a094 100644 > --- a/drivers/net/ethernet/airoha/airoha_eth.c > +++ b/drivers/net/ethernet/airoha/airoha_eth.c > @@ -1472,131 +1472,131 @@ static void airoha_update_hw_stats(struct airoha_gdm_port *port) > > /* TX */ > val = airoha_fe_rr(eth, REG_FE_GDM_TX_OK_PKT_CNT_H(port->id)); > - port->stats.tx_ok_pkts += ((u64)val << 32); > + u64_stats_add(&port->stats.tx_ok_pkts, (u64)val << 32); On 32-bit systems (ARCH_AIROHA is supported on ARM32 per arch/arm/Kconfig.platforms), does this lose the upper 32 bits of the counter? The u64_stats_add() signature is: static inline void u64_stats_add(u64_stats_t *p, unsigned long val) On 32-bit architectures, unsigned long is 32 bits. When (u64)val << 32 is passed, the resulting 64-bit value is truncated to unsigned long. Since all the non-zero bits are in the upper half, the truncation yields zero. The original code worked because the destination was u64: port->stats.tx_ok_pkts += ((u64)val << 32); This pattern appears 16 times in airoha_update_hw_stats() for all the _CNT_H registers (tx_ok_pkts, tx_ok_bytes, tx_len[], rx_ok_pkts, rx_ok_bytes, rx_len[]). On 32-bit builds, these counters would only accumulate the low 32 bits from the hardware. [ ... ] -- pw-bot: cr