From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFF263218BA for ; Fri, 14 Nov 2025 18:27:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763144860; cv=none; b=EVAQTxzYVQ1B4U/N4FGJmGzLN8Wy1FSVrJXwLj/lmRUYQR0rIEyqX01VuxfakYvTw4eWxpiNoyzMgbS1WvDgJ32RbOPvcGZ0bhxUmAMfcnkmWgR1QwtdtXEmb4LFkYvXstpAfXxc/OIHD0ukenacvd+u7FriI26eOCoMAIzipks= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763144860; c=relaxed/simple; bh=cYXp6vTHKD4+5HKyKDsS0LI6yssoViJnuOJ6XQWYNp4=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=tpB/cdY64/Dgz9dg7XyR5JyFxKBi1LjhIbL4mna1avGMlHlH5d0qBjJK0Bb7mz6yQiGLITwzMs8fKy6igFd+mc1cUGDhsUMhxWv57FDO7fuPGWvev/SKoj/Li5JDq1KvhK7LRVpeC3pcrR/4sE/vcjabg9dmdY5d75wcp86NVKU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hTdhkQKU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="hTdhkQKU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50B82C4CEF1; Fri, 14 Nov 2025 18:27:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763144860; bh=cYXp6vTHKD4+5HKyKDsS0LI6yssoViJnuOJ6XQWYNp4=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=hTdhkQKUi+PzhqiZrzsNxYV1ZF5i4s0dFL6ShBnirq9JvKqzo9WAtxlC9K4xNqREZ jMGFeVLCfm1GpAMgDDxYAhrOiDpRjmb0u2p8xMH3jLfpdHiGDgrjkPSTtOccX39msM QM0WIB+6+G1UIPFetlm0KsaA/yfiESW8bp2goJmd2NZ5COFKDrpjYKw4uvMvLEOPiT mjfAYyUCSTgc6Fqf4hyEBUlOChgPM8dgsfooBUkuXLZTBnJT9yFRS0GEX9IsPhlSUA lguFbUfMC0HYHxc/aswttWcArBbW3HbO2hNr+04smAX5GEmhFnLZUl8dAI8bL4J4X1 fUo+3KX2gZjNA== Date: Fri, 14 Nov 2025 12:27:39 -0600 From: Bjorn Helgaas To: Alex =?utf-8?Q?Benn=C3=A9e?= Cc: Ilpo =?utf-8?B?SsOkcnZpbmVu?= , Simon Richter , Lucas De Marchi , Alex Deucher , amd-gfx@lists.freedesktop.org, Bjorn Helgaas , David Airlie , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, Jani Nikula , Joonas Lahtinen , linux-pci@vger.kernel.org, Rodrigo Vivi , Simona Vetter , Tvrtko Ursulin , Christian =?utf-8?B?S8O2bmln?= , Thomas =?utf-8?Q?Hellstr=C3=B6m?= , =?utf-8?Q?Micha=C5=82?= Winiarski Subject: Re: [PATCH v2 00/11] PCI: BAR resizing fix/rework Message-ID: <20251114182739.GA2332823@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87pl9lot9r.fsf@draig.linaro.org> On Fri, Nov 14, 2025 at 09:30:56AM +0000, Alex Bennée wrote: > Ilpo Järvinen writes: > > > Hi all, > > > > Thanks to issue reports from Simon Richter and Alex Bennée, I > > discovered BAR resize rollback can corrupt the resource tree. As fixing > > corruption requires avoiding overlapping resource assignments, the > > correct fix can unfortunately results in worse user experience, what > > appeared to be "working" previously might no longer do so. Thus, I had > > to do a larger rework to pci_resize_resource() in order to properly > > restore resource states as it was prior to BAR resize. > > > > This rework has been on my TODO list anyway but it wasn't the highest > > prio item until pci_resize_resource() started to cause regressions due > > to other resource assignment algorithm changes. > > Thanks I'll have a look. > > Where does this apply? At least v6.17 doesn't seem to have > pbus_reassign_bridge_resources which 4/11 is trying to tweak. This is based on v6.18-rc1 and is applied here: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/log/?h=resource I expect some conflicts with d30203739be7 ("drm/xe: Move rebar to be done earlier"), which appeared in v6.18-rc2, and possibly with other DRM changes planned for v6.19. Bjorn