From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Date: Thu, 07 Apr 2022 00:25:32 +0000
Subject: Re: [PATCH 10/15] swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
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References: <20220404050559.132378-1-hch@lst.de>
 <20220404050559.132378-11-hch@lst.de>
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To: Christoph Hellwig <hch@lst.de>
Cc: iommu@lists.linux-foundation.org, x86@kernel.org, Anshuman Khandual <anshuman.khandual@arm.com>, Tom Lendacky <thomas.lendacky@amd.com>, Stefano Stabellini <sstabellini@kernel.org>, Boris Ostrovsky <boris.ostrovsky@oracle.com>, Juergen Gross <jgross@suse.com>, Joerg Roedel <joro@8bytes.org>, David Woodhouse <dwmw2@infradead.org>, Lu Baolu <baolu.lu@linux.intel.com>, Robin Murphy <robin.murphy@arm.com>, linux-arm-kernel@lists.infradead.org, xen-devel@lists.xenproject.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-hyperv@vger.kernel.org, tboot-devel@lists.sourceforge.net, linux-pci@vger.kernel.org

> diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c
> index c5228f4969eb2..3b4045d508ec8 100644
> --- a/arch/powerpc/platforms/pseries/svm.c
> +++ b/arch/powerpc/platforms/pseries/svm.c
> @@ -28,7 +28,7 @@ static int __init init_svm(void)
>  	 * need to use the SWIOTLB buffer for DMA even if dma_capable() says
>  	 * otherwise.
>  	 */
> -	swiotlb_force = SWIOTLB_FORCE;
> +	ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE;

This is the only place you set the ppc_swiotlb_flags.. so I wonder why
the '|=' instead of just '=' ?

Either way:
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Thank you!