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Date:   Fri, 14 Apr 2023 11:18:43 -0500
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc:     Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org,
        Rick Wertenbroek <rick.wertenbroek@gmail.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
        Manivannan Sadhasivam <mani@kernel.org>,
        Kishon Vijay Abraham I <kishon@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH v4 16/17] misc: pci_endpoint_test: Do not write status in
 IRQ handler
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On Thu, Mar 30, 2023 at 05:53:56PM +0900, Damien Le Moal wrote:
> pci_endpoint_test_irqhandler() always rewrites the status register when
> an IRQ is raised, either as-is if STATUS_IRQ_RAISED is not set, or with
> STATUS_IRQ_RAISED cleared if that flag is set. The first case creates a
> race window with the endpoint side, meaning that the host side test
> driver may end up reading what it just wrote, thus loosing the real
> status as set by the endpoint side before raising the next interrupt.
> This can prevent detecting that the STATUS_IRQ_RAISED flag was set by
> the endpoint.

s/loosing/losing/