linux-kernel - Re: [PATCH] PCI/P2PDMA: Fix a sleeping issue in a RCU read section

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Date: Thu, 4 Jan 2024 14:48:33 -0700
From: Logan Gunthorpe <logang@...tatee.com>
To: Christophe JAILLET <christophe.jaillet@...adoo.fr>,
 Bjorn Helgaas <bhelgaas@...gle.com>, Eric Dumazet <edumazet@...gle.com>
Cc: alexis.lothore@...tlin.com, linux-kernel@...r.kernel.org,
 kernel-janitors@...r.kernel.org, linux-pci@...r.kernel.org
Subject: Re: [PATCH] PCI/P2PDMA: Fix a sleeping issue in a RCU read section



On 2024-01-04 12:52, Christophe JAILLET wrote:
> It is not allowed to sleep within a RCU read section, so use GFP_ATOMIC
> instead of GFP_KERNEL here.
> 
> Fixes: ae21f835a5bd ("PCI/P2PDMA: Finish RCU conversion of pdev->p2pdma")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@...adoo.fr>

This makes sense to me. Though, the use of RCU could probably use a
review. Seeing p2pdma is only released through a devm action on the
pdev, I would think it shouldn't be needed if we hold a reference to the
pdev.

Other than that:

Reviewed-by: Logan Gunthorpe <logang@...tatee.com>

Thanks!

Logan