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From: Jason Gunthorpe <jgg@nvidia.com>
To: Alex Williamson <alex.williamson@nvidia.com>
Cc: Alex Williamson <alex@shazbot.org>, kvm <kvm@vger.kernel.org>,
	Kevin Tian <kevin.tian@intel.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	Yishai Hadas <yishaih@nvidia.com>,
	rananta@google.com, stable@vger.kernel.org
Subject: Re: [PATCH v2 1/2] vfio/pci: Fix racy bitfields and tighten struct layout
Date: Wed, 13 May 2026 09:31:16 -0300	[thread overview]
Message-ID: <20260513123116.GH7655@nvidia.com> (raw)
In-Reply-To: <20260512122355.22132e61@nvidia.com>

On Tue, May 12, 2026 at 12:23:55PM -0600, Alex Williamson wrote:

> It's not clear the bit compaction is worth the subtle RMW scenarios.
> What do you think, should we reserve bitfields for setup/release-time to
> avoid this class of issue or handle these as individual point fixes?

I think one patch is fine, just that every group of bitfields should
have a description what the locking rule is to write to
it. 'setup/release only' is a fine rule too

Otherwise the next person to add a bitfield will randomly select a
group and we will be back to this again..

Jason

  reply	other threads:[~2026-05-13 12:31 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20260511221609.3837652-1-alex.williamson@nvidia.com>
2026-05-11 22:16 ` [PATCH v2 1/2] vfio/pci: Fix racy bitfields and tighten struct layout Alex Williamson
2026-05-12 13:17   ` David Laight
2026-05-12 13:26     ` Alex Williamson
2026-05-12 13:18   ` Jason Gunthorpe
2026-05-12 18:23     ` Alex Williamson
2026-05-13 12:31       ` Jason Gunthorpe [this message]
2026-05-11 22:16 ` [PATCH v2 2/2] vfio/mlx5: " Alex Williamson

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