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Date: Sat, 6 Aug 2022 22:28:55 +0200
From: Joerg Roedel <joro@8bytes.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
	iommu@lists.linux.dev
Subject: Re: [git pull] IOMMU Updates for Linux v5.20
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On Sat, Aug 06, 2022 at 12:39:54PM -0700, Linus Torvalds wrote:
> I'm currently bisecting a boot failure on my desktop, and it's gone
> into the iommu code.
> 
> I'm assuming it's the 64-bit thing, but I'll bisect further to make sure.
> 
> If it is, it will be reverted as hopelessly optimistic.

A faster way to track down whether this change causes the boot failures
on your machine is to boot with iommu.forcedac=0 to disable the new
behavior and see if the issue goes away.

Please let me know if I can help with anything.

Regards,

	Joerg