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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 77E71CC6B1A for ; Wed, 14 Oct 2026 06:50:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CEBF810FB32; Wed, 14 Oct 2026 06:49:56 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3CAC310FB4A for ; Wed, 14 Oct 2026 06:49:50 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 00C394480A; Wed, 14 Oct 2026 06:49:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C7831F000FF; Wed, 14 Oct 2026 06:49:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791960589; bh=HsruFh9QO1GPcgzHM/eIN4QvMcLaW/LA6gWESnfZHSs=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=mVJlbiM/EP8ys9nyQRDJQ8sn/T7DsLfHRZN3r21zlTQW1lbP8DSx8EyerYncpPuIr gA8I/QGeDH/hEoLd1e+zjbQBZxG7gm8HTOMZljFD7QZTLouzkmL0DxR9Ce798ft153 TNzQNikJIS5F92B+DeqacWEJVvLtcSRxU6tplhlM1ezsfZXiCx6dsF7Fk+/SH62Zo0 PSrKysfbHH/CqRs960H2nixrrskAKRkm/4JMCreLuuzBC2PB8eq8zqS89yOaOofyQ+ 0pHTvN3JbWdeu49VRw0MT1hERXmPdsfhqdxp7bb8nSE4upQ3Od/TBgGvPoqsjF2M+E /3rft81V54rEw== Date: Wed, 14 Oct 2026 09:49:46 +0300 From: Leon Romanovsky To: sashiko-reviews@lists.linux.dev Cc: linux-pci@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, kvm@vger.kernel.org, media-ci@linuxtv.org Subject: Re: [PATCH v11 01/19] PCI/P2PDMA: Honor device-specific ACS redirection Message-ID: <20261014064946.GU219304@unreal> References: <20261013-fix-p2p-acs-v4-0-v11-0-72cf8c96e617@nvidia.com> <20261013-fix-p2p-acs-v4-0-v11-1-72cf8c96e617@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, Oct 13, 2026 at 02:44:37PM +0000, sashiko-bot@kernel.org wrote: > Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: > - [High] pci/p2pdma: deadlock in calc_map_type_and_dist() calling xa_store() from softirq > -- > > commit 6120f97b22446453f3e4fa09135e1a44135ecfe8 > Author: Leon Romanovsky > > PCI/P2PDMA: Honor device-specific ACS redirection > > This commit updates PCI P2PDMA to respect device-specific ACS redirection > quirks for switches and ports that redirect peer-to-peer traffic without a > standard ACS capability. It queries quirks to set Request and Completion > Redirect flags and modifies how affected ports are warned about. > > > diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c > > index 45260423dfb09..ba94b0f339285 100644 > > --- a/drivers/pci/p2pdma.c > > +++ b/drivers/pci/p2pdma.c > [ ... ] > > @@ -782,15 +867,8 @@ calc_map_type_and_dist(struct pci_dev *provider, struct pci_dev *client, > > goto done; > > } > > > > - if (verbose) { > > - /* Drop the final semicolon; the list is not empty here */ > > - if (!seq_buf_has_overflowed(&acs_list)) > > - acs_list.buffer[acs_list.len - 1] = '\0'; > > - pci_warn(client, "ACS redirect is set between the client and provider (%s)\n", > > - pci_name(provider)); > > - pci_warn(client, "to disable ACS redirect for this path, add the kernel parameter: pci=disable_acs_redir=%s\n", > > - seq_buf_str(&acs_list)); > > - } > > + if (verbose) > > + pci_p2pdma_warn_redir(client, provider, &acs_list, &quirk_list); > > > > map_through_host_bridge: > > if (!cpu_supports_p2pdma() && > > [Severity: High] > Does calling xa_store() further down in this function risk a deadlock? Not in the current code base, I failed to find any reliable path for it. Thanks