linux-kernel - Re: [PATCH v16 3/6] soc: qcom: rpmh: Invalidate SLEEP and WAKE TCSes before flushing new data

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 09 Apr 2020 13:23:14 -0700
From:   Stephen Boyd <swboyd@...omium.org>
To:     Maulik Shah <mkshah@...eaurora.org>, bjorn.andersson@...aro.org,
        dianders@...omium.org, evgreen@...omium.org
Cc:     linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        agross@...nel.org, mka@...omium.org, rnayak@...eaurora.org,
        ilina@...eaurora.org, lsrao@...eaurora.org,
        Maulik Shah <mkshah@...eaurora.org>
Subject: Re: [PATCH v16 3/6] soc: qcom: rpmh: Invalidate SLEEP and WAKE TCSes before flushing new data

Quoting Maulik Shah (2020-04-05 23:32:18)
> TCSes have previously programmed data when rpmh_flush is called.

rpmh_flush()

> This can cause old data to trigger along with newly flushed.
> 
> Fix this by cleaning SLEEP and WAKE TCSes before new data is flushed.
> 
> With this there is no need to invoke rpmh_rsc_invalidate() call from
> rpmh_invalidate().
> 
> Simplify rpmh_invalidate() by moving invalidate_batch() inside.
> 
> Fixes: 600513dfeef3 ("drivers: qcom: rpmh: cache sleep/wake state requests")
> Signed-off-by: Maulik Shah <mkshah@...eaurora.org>
> Reviewed-by: Douglas Anderson <dianders@...omium.org>
> ---
>  drivers/soc/qcom/rpmh.c | 41 ++++++++++++++++++-----------------------
>  1 file changed, 18 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
> index 03630ae..a75f3df 100644
> --- a/drivers/soc/qcom/rpmh.c
> +++ b/drivers/soc/qcom/rpmh.c
> @@ -498,24 +492,25 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr)
>  }
>  
>  /**
> - * rpmh_invalidate: Invalidate all sleep and active sets
> - * sets.
> + * rpmh_invalidate: Invalidate sleep and wake sets in batch_cache
>   *
>   * @dev: The device making the request
>   *
> - * Invalidate the sleep and active values in the TCS blocks.
> + * Invalidate the sleep and wake values in batch_cache.
>   */
>  int rpmh_invalidate(const struct device *dev)
>  {
>         struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
> -       int ret;
> -
> -       invalidate_batch(ctrlr);
> +       struct batch_cache_req *req, *tmp;
> +       unsigned long flags;
>  
> -       do {
> -               ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
> -       } while (ret == -EAGAIN);
> +       spin_lock_irqsave(&ctrlr->cache_lock, flags);
> +       list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
> +               kfree(req);
> +       INIT_LIST_HEAD(&ctrlr->batch_cache);
> +       ctrlr->dirty = true;
> +       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
>  
> -       return ret;
> +       return 0;

Now this always returns 0. Maybe it should become a void function, but
doing that requires a change in the interconnect code so maybe do it
later.