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To:     Joerg Roedel <joro@8bytes.org>
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 <YLpIcwdWDGKpw39s@8bytes.org>
From:   Xingang Wang <wangxingang5@huawei.com>
Subject: Re: [PATCH v4] iommu/of: Fix pci_request_acs() before enumerating PCI
 devices
Message-ID: <9054b39b-a73c-f5b4-cd61-9af4449a0649@huawei.com>
Date:   Mon, 7 Jun 2021 20:43:53 +0800
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On 2021/6/4 23:36, Joerg Roedel wrote:
> On Fri, May 21, 2021 at 03:03:24AM +0000, Wang Xingang wrote:
>> From: Xingang Wang <wangxingang5@huawei.com>
>>
>> When booting with devicetree, the pci_request_acs() is called after the
>> enumeration and initialization of PCI devices, thus the ACS is not
>> enabled. And ACS should be enabled when IOMMU is detected for the
>> PCI host bridge, so add check for IOMMU before probe of PCI host and call
>> pci_request_acs() to make sure ACS will be enabled when enumerating PCI
>> devices.
>>
>> Fixes: 6bf6c24720d33 ("iommu/of: Request ACS from the PCI core when
>> configuring IOMMU linkage")
>> Signed-off-by: Xingang Wang <wangxingang5@huawei.com>
>> ---
>>   drivers/iommu/of_iommu.c | 1 -
>>   drivers/pci/of.c         | 8 +++++++-
>>   2 files changed, 7 insertions(+), 2 deletions(-)
> 
> Should probably go through the PCI tree, so
> 
> Acked-by: Joerg Roedel <jroedel@suse.de>
> 
> .
> 

Thanks

.