Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
Date:   Tue, 5 Apr 2022 09:42:37 -0600
From:   dann frazier <dann.frazier@canonical.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Marc Zyngier <maz@kernel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Rob Herring <robh@kernel.org>,
        Toan Le <toan@os.amperecomputing.com>,
        Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        =?iso-8859-1?Q?St=E9phane?= Graber <stgraber@ubuntu.com>
Subject: Re: [PATCH 5.16 0199/1017] PCI: xgene: Revert "PCI: xgene: Fix IB
 window setup"
Message-ID: <YkxjbVp3W2LeVIeL@xps13.dannf>
References: <20220405070354.155796697@linuxfoundation.org>
 <20220405070400.156176848@linuxfoundation.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20220405070400.156176848@linuxfoundation.org>
Precedence: bulk

On Tue, Apr 05, 2022 at 09:18:32AM +0200, Greg Kroah-Hartman wrote:
> From: Marc Zyngier <maz@kernel.org>
> 
> commit 825da4e9cec68713fbb02dc6f71fe1bf65fe8050 upstream.
> 
> Commit c7a75d07827a ("PCI: xgene: Fix IB window setup") tried to
> fix the damages that 6dce5aa59e0b ("PCI: xgene: Use inbound resources
> for setup") caused, but actually didn't improve anything for some
> plarforms (at least Mustang and m400 are still broken).
> 
> Given that 6dce5aa59e0b has been reverted, revert this patch as well,
> restoring the PCIe support on XGene to its pre-5.5, working state.
> 
> Link: https://lore.kernel.org/r/YjN8pT5e6/8cRohQ@xps13.dannf
> Link: https://lore.kernel.org/r/20220321104843.949645-3-maz@kernel.org
> Fixes: c7a75d07827a ("PCI: xgene: Fix IB window setup")
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: stable@vger.kernel.org
> Cc: Rob Herring <robh@kernel.org>
> Cc: Toan Le <toan@os.amperecomputing.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Krzysztof Wilczyński <kw@linux.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Stéphane Graber <stgraber@ubuntu.com>
> Cc: dann frazier <dann.frazier@canonical.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/pci/controller/pci-xgene.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Hi Greg,

  I don't think it makes sense to apply this to 5.10.y, 5.15.y &
5.16.y w/o also applying a backport of 1874b6d7ab1, because without
that we will regress support for Stéphane's X-Gene2-based systems. The
backport of 1874b6d7ab1 was rejected for these trees because it doesn't
apply cleanly, but I've just submitted new versions that do.

  -dann