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Date: Thu, 8 Feb 2024 12:09:32 -0400
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Nikhil V <quic_nprakash@quicinc.com>
Cc: Robin Murphy <robin.murphy@arm.com>, Will Deacon <will@kernel.org>,
	Joerg Roedel <joro@8bytes.org>,
	Charan Teja Kalla <quic_charante@quicinc.com>,
	iommu@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] iommu: Avoid races around default domain allocations
Message-ID: <20240208160932.GT31743@ziepe.ca>
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On Thu, Feb 08, 2024 at 08:47:42PM +0530, Nikhil V wrote:

> Also, as Jason pointed out, this fix would not allow changing the
> default domain for an iommu group. We didn't have any usecase for
> changing default domain, hence couldn't see any issues with the fix
> proposed. So, we would have to rework the patch for it to be
> upstream ready. Any suggestions for this would be really helpful and
> appreciated. Thanks!!!

I think you can lift and duplicate the check into the callers and that
way restrict it only to the probe paths.

Jason