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 AA9C2C433EF for ; Fri, 4 Feb 2022 09:23:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357495AbiBDJW6 (ORCPT ); Fri, 4 Feb 2022 04:22:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357531AbiBDJWM (ORCPT ); Fri, 4 Feb 2022 04:22:12 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 668D6C061760; Fri, 4 Feb 2022 01:22:11 -0800 (PST) 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 CD5A46162C; Fri, 4 Feb 2022 09:22:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B08BBC004E1; Fri, 4 Feb 2022 09:22:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643966530; bh=WaDGmJ3k0j4stp3NMd9qs5wTtfDR4VHH69jQNzw4zAA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iomp+G4sVDLziErQcGM0Rky/Zb3qb0+llMa2lkeverZ+jLIu++wGF1fZQ+qUrPO1z jL9AswVhN5Qd9A005ItC9kohFsoKVcEDyHf2HdyVDDINlzRKzxAT1HY7M1bt/pBz7b uyI43jfZfxm2+YO6LcrJnLGERiLUGtdavuWOtBRU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alex Elder , "David S. Miller" Subject: [PATCH 5.10 04/25] net: ipa: prevent concurrent replenish Date: Fri, 4 Feb 2022 10:20:11 +0100 Message-Id: <20220204091914.428884604@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220204091914.280602669@linuxfoundation.org> References: <20220204091914.280602669@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: linux-kernel@vger.kernel.org From: Alex Elder commit 998c0bd2b3715244da7639cc4e6a2062cb79c3f4 upstream. We have seen cases where an endpoint RX completion interrupt arrives while replenishing for the endpoint is underway. This causes another instance of replenishing to begin as part of completing the receive transaction. If this occurs it can lead to transaction corruption. Use a new flag to ensure only one replenish instance for an endpoint executes at a time. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ipa/ipa_endpoint.c | 12 ++++++++++++ drivers/net/ipa/ipa_endpoint.h | 2 ++ 2 files changed, 14 insertions(+) --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -907,16 +907,27 @@ static void ipa_endpoint_replenish(struc return; } + /* If already active, just update the backlog */ + if (test_and_set_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags)) { + if (count) + atomic_add(count, &endpoint->replenish_backlog); + return; + } while (atomic_dec_not_zero(&endpoint->replenish_backlog)) if (ipa_endpoint_replenish_one(endpoint)) goto try_again_later; + + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); + if (count) atomic_add(count, &endpoint->replenish_backlog); return; try_again_later: + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); + /* The last one didn't succeed, so fix the backlog */ backlog = atomic_add_return(count + 1, &endpoint->replenish_backlog); @@ -1470,6 +1481,7 @@ static void ipa_endpoint_setup_one(struc * backlog is the same as the maximum outstanding TREs. */ clear_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags); + clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags); atomic_set(&endpoint->replenish_saved, gsi_channel_tre_max(gsi, endpoint->channel_id)); atomic_set(&endpoint->replenish_backlog, 0); --- a/drivers/net/ipa/ipa_endpoint.h +++ b/drivers/net/ipa/ipa_endpoint.h @@ -43,10 +43,12 @@ enum ipa_endpoint_name { * enum ipa_replenish_flag: RX buffer replenish flags * * @IPA_REPLENISH_ENABLED: Whether receive buffer replenishing is enabled + * @IPA_REPLENISH_ACTIVE: Whether replenishing is underway * @IPA_REPLENISH_COUNT: Number of defined replenish flags */ enum ipa_replenish_flag { IPA_REPLENISH_ENABLED, + IPA_REPLENISH_ACTIVE, IPA_REPLENISH_COUNT, /* Number of flags (must be last) */ };