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 4682BC04A68 for ; Wed, 27 Jul 2022 17:38:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242548AbiG0RiW (ORCPT ); Wed, 27 Jul 2022 13:38:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242653AbiG0RiD (ORCPT ); Wed, 27 Jul 2022 13:38:03 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D578086C27; Wed, 27 Jul 2022 09:50:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 09BDE616BD; Wed, 27 Jul 2022 16:50:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16A7AC433C1; Wed, 27 Jul 2022 16:50:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658940617; bh=S0pWMV/TRcjMiJTSJysZSUB2PC/SsjxITO9QWcWCoMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Rxr+1ZWryFBFCdb5UQbONkUKmBnfryXCztkS59EsOEC2VDIWl0PXBfCIjDa3+2LJr GS0u7tdeQs+K6rud937Njr2+YviQRYpC/2JiNg4svtH3evqKTcgHTdwoP03FuMyF3h OBhcHGqYU1/GJ3xergB+OHN+tQ0fIKG8C7PycYcY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Horatiu Vultur , Vladimir Oltean , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.18 087/158] net: lan966x: Fix usage of lan966x->mac_lock inside lan966x_mac_irq_handler Date: Wed, 27 Jul 2022 18:12:31 +0200 Message-Id: <20220727161024.965216524@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220727161021.428340041@linuxfoundation.org> References: <20220727161021.428340041@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Horatiu Vultur [ Upstream commit c1924684369762b112428a333ad00eac6ca89d96 ] The problem with this spin lock is that it was just protecting the list of the MAC entries in SW and not also the access to the MAC entries in HW. Because the access to HW is indirect, then it could happen to have race conditions. For example when SW introduced an entry in MAC table and the irq mac is trying to read something from the MAC. Update such that also the access to MAC entries in HW is protected by this lock. Fixes: 5ccd66e01cbef ("net: lan966x: add support for interrupts from analyzer") Signed-off-by: Horatiu Vultur Reviewed-by: Vladimir Oltean Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- .../ethernet/microchip/lan966x/lan966x_mac.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c b/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c index d0b8eba0a66d..69e343b7f4af 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_mac.c @@ -183,7 +183,7 @@ static struct lan966x_mac_entry *lan966x_mac_alloc_entry(const unsigned char *ma { struct lan966x_mac_entry *mac_entry; - mac_entry = kzalloc(sizeof(*mac_entry), GFP_KERNEL); + mac_entry = kzalloc(sizeof(*mac_entry), GFP_ATOMIC); if (!mac_entry) return NULL; @@ -310,8 +310,8 @@ void lan966x_mac_purge_entries(struct lan966x *lan966x) spin_lock(&lan966x->mac_lock); list_for_each_entry_safe(mac_entry, tmp, &lan966x->mac_entries, list) { - lan966x_mac_forget(lan966x, mac_entry->mac, mac_entry->vid, - ENTRYTYPE_LOCKED); + lan966x_mac_forget_locked(lan966x, mac_entry->mac, + mac_entry->vid, ENTRYTYPE_LOCKED); list_del(&mac_entry->list); kfree(mac_entry); @@ -427,13 +427,14 @@ static void lan966x_mac_irq_process(struct lan966x *lan966x, u32 row, if (WARN_ON(dest_idx >= lan966x->num_phys_ports)) continue; + spin_lock(&lan966x->mac_lock); mac_entry = lan966x_mac_alloc_entry(mac, vid, dest_idx); - if (!mac_entry) + if (!mac_entry) { + spin_unlock(&lan966x->mac_lock); return; + } mac_entry->row = row; - - spin_lock(&lan966x->mac_lock); list_add_tail(&mac_entry->list, &lan966x->mac_entries); spin_unlock(&lan966x->mac_lock); @@ -455,6 +456,7 @@ irqreturn_t lan966x_mac_irq_handler(struct lan966x *lan966x) lan966x, ANA_MACTINDX); while (1) { + spin_lock(&lan966x->mac_lock); lan_rmw(ANA_MACACCESS_MAC_TABLE_CMD_SET(MACACCESS_CMD_SYNC_GET_NEXT), ANA_MACACCESS_MAC_TABLE_CMD, lan966x, ANA_MACACCESS); @@ -478,12 +480,15 @@ irqreturn_t lan966x_mac_irq_handler(struct lan966x *lan966x) stop = false; if (column == LAN966X_MAC_COLUMNS - 1 && - index == 0 && stop) + index == 0 && stop) { + spin_unlock(&lan966x->mac_lock); break; + } entry[column].mach = lan_rd(lan966x, ANA_MACHDATA); entry[column].macl = lan_rd(lan966x, ANA_MACLDATA); entry[column].maca = lan_rd(lan966x, ANA_MACACCESS); + spin_unlock(&lan966x->mac_lock); /* Once all the columns are read process them */ if (column == LAN966X_MAC_COLUMNS - 1) { -- 2.35.1