From: Nicolas Pitre <npitre@baylibre.com>
To: Julien Panis <jpanis@baylibre.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Zhang Rui <rui.zhang@intel.com>,
Lukasz Luba <lukasz.luba@arm.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>,
linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Subject: Re: [PATCH 2/2] thermal/drivers/mediatek/lvts_thermal: Fix wrong lvts_ctrl index
Date: Fri, 3 May 2024 11:45:48 -0400 (EDT) [thread overview]
Message-ID: <qppo2o23-40r4-956p-9n35-p0556sp32spq@onlyvoer.pbz> (raw)
In-Reply-To: <20240503-mtk-thermal-lvts-ctrl-idx-fix-v1-2-f605c50ca117@baylibre.com>
On Fri, 3 May 2024, Julien Panis wrote:
> In 'lvts_should_update_thresh()' and 'lvts_ctrl_start()' functions,
> the parameter passed to 'lvts_for_each_valid_sensor()' macro is always
> 'lvts_ctrl->lvts_data->lvts_ctrl'. In other words, the array index 0
> is systematically passed as 'struct lvts_ctrl_data' type item, even
> when another item should be consumed instead.
>
> Hence, the 'valid_sensor_mask' value which is selected can be wrong
> because unrelated to the 'struct lvts_ctrl_data' type item that should
> be used. Hence, some thermal zone can be registered for a sensor 'i'
> that does not actually exist. Because of the invalid address used
> as 'lvts_sensor[i].msr', this situation ends up with a crash in
> 'lvts_get_temp()' function, where this 'msr' pointer is passed to
> 'readl_poll_timeout()' function. The following message is output:
> "Unable to handle kernel NULL pointer dereference at virtual
> address <msr>", with <msr> = 0.
>
> This patch fixes the issue.
>
> Fixes: 11e6f4c31447 ("thermal/drivers/mediatek/lvts_thermal: Allow early empty sensor slots")
> Signed-off-by: Julien Panis <jpanis@baylibre.com>
Reviewed-by: Nicolas Pitre <npitre@baylibre.com>
> ---
> drivers/thermal/mediatek/lvts_thermal.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/thermal/mediatek/lvts_thermal.c b/drivers/thermal/mediatek/lvts_thermal.c
> index 18a796386cd0..d7df6f09938b 100644
> --- a/drivers/thermal/mediatek/lvts_thermal.c
> +++ b/drivers/thermal/mediatek/lvts_thermal.c
> @@ -116,9 +116,9 @@ struct lvts_ctrl_data {
> ((s2) ? BIT(2) : 0) | \
> ((s3) ? BIT(3) : 0))
>
> -#define lvts_for_each_valid_sensor(i, lvts_ctrl_data) \
> +#define lvts_for_each_valid_sensor(i, lvts_ctrl) \
> for ((i) = 0; (i) < LVTS_SENSOR_MAX; (i)++) \
> - if (!((lvts_ctrl_data)->valid_sensor_mask & BIT(i))) \
> + if (!((lvts_ctrl)->valid_sensor_mask & BIT(i))) \
> continue; \
> else
>
> @@ -145,6 +145,7 @@ struct lvts_ctrl {
> const struct lvts_data *lvts_data;
> u32 calibration[LVTS_SENSOR_MAX];
> u32 hw_tshut_raw_temp;
> + u8 valid_sensor_mask;
> int mode;
> void __iomem *base;
> int low_thresh;
> @@ -356,7 +357,7 @@ static bool lvts_should_update_thresh(struct lvts_ctrl *lvts_ctrl, int high)
> if (high > lvts_ctrl->high_thresh)
> return true;
>
> - lvts_for_each_valid_sensor(i, lvts_ctrl->lvts_data->lvts_ctrl)
> + lvts_for_each_valid_sensor(i, lvts_ctrl)
> if (lvts_ctrl->sensors[i].high_thresh == lvts_ctrl->high_thresh
> && lvts_ctrl->sensors[i].low_thresh == lvts_ctrl->low_thresh)
> return false;
> @@ -617,6 +618,8 @@ static int lvts_sensor_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
> lvts_sensor[i].high_thresh = INT_MIN;
> };
>
> + lvts_ctrl->valid_sensor_mask = lvts_ctrl_data->valid_sensor_mask;
> +
> return 0;
> }
>
> @@ -1112,7 +1115,7 @@ static int lvts_ctrl_start(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> u32 *sensor_bitmap = lvts_ctrl->mode == LVTS_MSR_IMMEDIATE_MODE ?
> sensor_imm_bitmap : sensor_filt_bitmap;
>
> - lvts_for_each_valid_sensor(i, lvts_ctrl->lvts_data->lvts_ctrl) {
> + lvts_for_each_valid_sensor(i, lvts_ctrl) {
>
> int dt_id = lvts_sensors[i].dt_id;
>
>
> --
> 2.37.3
>
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2024-05-03 15:46 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-03 15:35 [PATCH 0/2] Mediatek lvts_thermal driver: Fix wrong lvts_ctrl index Julien Panis
2024-05-03 15:35 ` [PATCH 1/2] thermal/drivers/mediatek/lvts_thermal: Remove unused members from struct lvts_ctrl_data Julien Panis
2024-05-03 15:46 ` Nicolas Pitre
2024-05-06 7:52 ` AngeloGioacchino Del Regno
2024-05-03 15:35 ` [PATCH 2/2] thermal/drivers/mediatek/lvts_thermal: Fix wrong lvts_ctrl index Julien Panis
2024-05-03 15:45 ` Nicolas Pitre [this message]
2024-05-06 7:52 ` AngeloGioacchino Del Regno
2024-05-03 17:23 ` [PATCH 0/2] Mediatek lvts_thermal driver: " Daniel Lezcano
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=qppo2o23-40r4-956p-9n35-p0556sp32spq@onlyvoer.pbz \
--to=npitre@baylibre.com \
--cc=angelogioacchino.delregno@collabora.com \
--cc=daniel.lezcano@linaro.org \
--cc=jpanis@baylibre.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=linux-pm@vger.kernel.org \
--cc=lukasz.luba@arm.com \
--cc=matthias.bgg@gmail.com \
--cc=rafael@kernel.org \
--cc=rui.zhang@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).