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 6A0DCC61DF4 for ; Fri, 24 Nov 2023 12:53:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=H8X3n39j10T/fW8CH/9hf153IcMhwCPyynpTwdSQQ7M=; b=Wbxbs0uHwnHCY8 lN8FV/ZKbkXlD9pemjwcSZRKNpko1+YiSwrJwTK+FWD7sWEobGwTiA0RlLErHN1MuIHQi8P33xHBp yyUeu+R18SH0AcDH0bkFKEa0u0lLd7cLCoBqO0Bz8qGmL+GJPatJaGhlufxIVKWXBLSEf49yCDcJk /oJXDWy2PLOodLKfdSCyWb79En00PDrB3XiTvl4tEsYpSiYlGj2s2zsILoyTLZ5KW/IE58a692CIe 5TKcUyBs0257NSdtcErNqUJygeI/ROXEXFBYq5WmaqATuqH2lNrcVkFdSXc1mhHvmLRcKvsbNOxCK QTDx+l14FnrWTHw1fhUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1r6VgW-007FHM-0Y; Fri, 24 Nov 2023 12:53:28 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1r6VgT-007FG2-0o for linux-arm-kernel@lists.infradead.org; Fri, 24 Nov 2023 12:53:27 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id B1B73CE285B; Fri, 24 Nov 2023 12:53:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79279C433C7; Fri, 24 Nov 2023 12:53:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700830401; bh=jDYI24ELCvDTS98bS4B1Y7XrA4wLz6GtcIczEr1aodo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VZqKYnIUVvr1DuFPlEOpgbiwKJCCFaOv9LTFqBLeA49yywjaB//k5rEIoc1JXAOsY 2i0pGQMJAXMYKG5I+cdNY2IkGLkKsdXdF+OSrHDGdZf8rAYJzwkbaC1ENFQfHybCXT CytGgpbeaPCx14LaK4fE8BdabYgwAgSUXC6IOnzpZxEw8ikqAwUfT+4keNaPPJ7FPL lGC0q8PKYO1q7bqvLg5drluWEJ+AumO59ntpiiJeMvN6Aq4n90etbh8kgWvIA7lFws 480LN64i6+4az6DfNu3nYKzU3ybINn6hrKWZEXvnnjxkCDqmYOShWEFWVeTyJwxpMD 2yOegHEH77jSQ== Date: Fri, 24 Nov 2023 18:23:16 +0530 From: Vinod Koul To: Thomas Pfaff Subject: Re: [PATCH RFC 1/2 stable-6.1] dmaengine: at_hdmac: get next dma transfer from the right list Message-ID: References: <15c92c2f-71e7-f4fd-b90b-412ab53e5a25@pcs.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <15c92c2f-71e7-f4fd-b90b-412ab53e5a25@pcs.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231124_045325_761809_A1530E03 X-CRM114-Status: GOOD ( 20.65 ) 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: , Cc: tudor.ambarus@microchip.com, linux-kernel@vger.kernel.org, ludovic.desroches@microchip.com, dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 14-11-23, 13:22, Thomas Pfaff wrote: > From: Thomas Pfaff > > In kernel 6.1, atc_advance_work and atc_handle_error are checking for the > next dma transfer inside active list, but the descriptor is taken from the > queue instead. Sorry that is not how this works. Please send the patch for mainline and add a stable tag to the patches. They will be backported to stable kernels Also, your patch threading is broken, they appear disjoint and not as a series Thanks > > Signed-off-by: Thomas Pfaff > --- > diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c > index 858bd64f1313..68c1bfbefc5c 100644 > --- a/drivers/dma/at_hdmac.c > +++ b/drivers/dma/at_hdmac.c > @@ -490,6 +490,27 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) > } > } > > +/** > + * atc_start_next - start next pending transaction if any > + * @atchan: channel where the transaction ended > + * > + * Called with atchan->lock held > + */ > +static void atc_start_next(struct at_dma_chan *atchan) > +{ > + struct at_desc *desc = NULL; > + > + if (!list_empty(&atchan->active_list)) > + desc = atc_first_active(atchan); > + else if (!list_empty(&atchan->queue)) { > + desc = atc_first_queued(atchan); > + list_move_tail(&desc->desc_node, &atchan->active_list); > + } > + > + if (desc) > + atc_dostart(atchan, desc); > +} > + > /** > * atc_advance_work - at the end of a transaction, move forward > * @atchan: channel where the transaction ended > @@ -513,11 +534,7 @@ static void atc_advance_work(struct at_dma_chan *atchan) > > /* advance work */ > spin_lock_irqsave(&atchan->lock, flags); > - if (!list_empty(&atchan->active_list)) { > - desc = atc_first_queued(atchan); > - list_move_tail(&desc->desc_node, &atchan->active_list); > - atc_dostart(atchan, desc); > - } > + atc_start_next(atchan); > spin_unlock_irqrestore(&atchan->lock, flags); > } > > @@ -529,7 +546,6 @@ static void atc_advance_work(struct at_dma_chan *atchan) > static void atc_handle_error(struct at_dma_chan *atchan) > { > struct at_desc *bad_desc; > - struct at_desc *desc; > struct at_desc *child; > unsigned long flags; > > @@ -543,11 +559,7 @@ static void atc_handle_error(struct at_dma_chan *atchan) > list_del_init(&bad_desc->desc_node); > > /* Try to restart the controller */ > - if (!list_empty(&atchan->active_list)) { > - desc = atc_first_queued(atchan); > - list_move_tail(&desc->desc_node, &atchan->active_list); > - atc_dostart(atchan, desc); > - } > + atc_start_next(atchan); > > /* > * KERN_CRITICAL may seem harsh, but since this only happens > -- ~Vinod _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel