Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20200803072857.8880-1-madhuparnabhowmik10@gmail.com>
In-Reply-To: <20200803072857.8880-1-madhuparnabhowmik10@gmail.com>
From:   Ulf Hansson <ulf.hansson@linaro.org>
Date:   Fri, 21 Aug 2020 14:48:37 +0200
Message-ID: <CAPDyKFo2njN6bU+VqpuHPpHDx4+ZkuoNRZVb0a0EjGBi9uXa7g@mail.gmail.com>
Subject: Re: [PATCH] drivers: mmc: host: via-sdmmc: Fix data race bug
To:     madhuparnabhowmik10@gmail.com
Cc:     Bruce Chang <brucechang@via.com.tw>,
        Harald Welte <HaraldWelte@viatech.com>,
        "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        ldv-project@linuxtesting.org, andrianov@ispras.ru
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, 3 Aug 2020 at 09:29, <madhuparnabhowmik10@gmail.com> wrote:
>
> From: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
>
> via_save_pcictrlreg() should be called with host->lock held
> as it writes to pm_pcictrl_reg, otherwise there can be a race
> condition between via_sd_suspend() and via_sdc_card_detect().
> The same pattern is used in the function via_reset_pcictrl()
> as well, where via_save_pcictrlreg() is called with host->lock
> held.
>
> Found by Linux Driver Verification project (linuxtesting.org).
>
> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>

This doesn't apply to my mmc tree, can you please rebase and submit a
new version.

Kind regards
Uffe

> ---
>  drivers/mmc/host/via-sdmmc.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mmc/host/via-sdmmc.c b/drivers/mmc/host/via-sdmmc.c
> index ef95bce50889..e4d8126cd4e5 100644
> --- a/drivers/mmc/host/via-sdmmc.c
> +++ b/drivers/mmc/host/via-sdmmc.c
> @@ -1259,11 +1259,14 @@ static void via_init_sdc_pm(struct via_crdr_mmc_host *host)
>  static int via_sd_suspend(struct pci_dev *pcidev, pm_message_t state)
>  {
>         struct via_crdr_mmc_host *host;
> +       unsigned long flags;
>
>         host = pci_get_drvdata(pcidev);
>
> +       spin_lock_irqsave(&host->lock, flags);
>         via_save_pcictrlreg(host);
>         via_save_sdcreg(host);
> +       spin_unlock_irqrestore(&host->lock, flags);
>
>         pci_save_state(pcidev);
>         pci_enable_wake(pcidev, pci_choose_state(pcidev, state), 0);
> --
> 2.17.1
>