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Message-ID: <93c4acb4-94be-425d-ae10-92e1096139ae@intel.com>
Date: Fri, 8 Mar 2024 12:45:52 -0800
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 2/7] vfio/pci: Lock external INTx masking ops
Content-Language: en-US
To: Alex Williamson <alex.williamson@redhat.com>
CC: <kvm@vger.kernel.org>, <eric.auger@redhat.com>, <clg@redhat.com>,
	<linux-kernel@vger.kernel.org>, <kevin.tian@intel.com>
References: <20240306211445.1856768-1-alex.williamson@redhat.com>
 <20240306211445.1856768-3-alex.williamson@redhat.com>
From: Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <20240306211445.1856768-3-alex.williamson@redhat.com>
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Hi Alex,

On 3/6/2024 1:14 PM, Alex Williamson wrote:
> Mask operations through config space changes to DisINTx may race INTx
> configuration changes via ioctl.  Create wrappers that add locking for
> paths outside of the core interrupt code.
> 
> In particular, irq_type is updated holding igate, therefore testing
> is_intx() requires holding igate.  For example clearing DisINTx from
> config space can otherwise race changes of the interrupt configuration.
> 
> This aligns interfaces which may trigger the INTx eventfd into two
> camps, one side serialized by igate and the other only enabled while
> INTx is configured.  A subsequent patch introduces synchronization for
> the latter flows.
> 
> Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver")
> Reported-by: Reinette Chatre <reinette.chatre@intel.com>
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> ---

Thank you very much.

Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Reinette