| 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
| ||
|
Date: Wed, 16 Aug 2023 15:58:34 +0530
From: Kalesh Anakkur Purayil <kalesh-anakkur.purayil@...adcom.com>
To: Guenter Roeck <linux@...ck-us.net>
Cc: Michael Chan <michael.chan@...adcom.com>, davem@...emloft.net, netdev@...r.kernel.org,
edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com, gospo@...adcom.com,
Jean Delvare <jdelvare@...e.com>, linux-hwmon@...r.kernel.org
Subject: Re: [PATCH net-next 11/12] bnxt_en: Expose threshold temperatures
through hwmon
Thank you Guenter for the review and the suggestions.
Please see my response inline.
On Tue, Aug 15, 2023 at 8:35 PM Guenter Roeck <linux@...ck-us.net> wrote:
> On Mon, Aug 14, 2023 at 09:56:57PM -0700, Michael Chan wrote:
> > From: Kalesh AP <kalesh-anakkur.purayil@...adcom.com>
> >
> > HWRM_TEMP_MONITOR_QUERY response now indicates various
> > threshold temperatures. Expose these threshold temperatures
> > through the hwmon sysfs.
> > Also, provide temp1_max_alarm through which the user can check
> > whether the threshold temperature has been reached or not.
> >
> > Example:
> > cat /sys/class/hwmon/hwmon3/temp1_input
> > 75000
> > cat /sys/class/hwmon/hwmon3/temp1_max
> > 105000
> > cat /sys/class/hwmon/hwmon3/temp1_max_alarm
> > 0
> >
> > Cc: Jean Delvare <jdelvare@...e.com>
> > Cc: Guenter Roeck <linux@...ck-us.net>
> > Cc: linux-hwmon@...r.kernel.org
> > Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@...adcom.com>
> > Signed-off-by: Michael Chan <michael.chan@...adcom.com>
> > ---
> > drivers/net/ethernet/broadcom/bnxt/bnxt.h | 7 ++
> > .../net/ethernet/broadcom/bnxt/bnxt_hwmon.c | 71 +++++++++++++++++--
> > 2 files changed, 73 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> > index 84cbcfa61bc1..43a07d84f815 100644
> > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
> > @@ -2013,6 +2013,7 @@ struct bnxt {
> > #define BNXT_FW_CAP_RING_MONITOR BIT_ULL(30)
> > #define BNXT_FW_CAP_DBG_QCAPS BIT_ULL(31)
> > #define BNXT_FW_CAP_PTP BIT_ULL(32)
> > + #define BNXT_FW_CAP_THRESHOLD_TEMP_SUPPORTED BIT_ULL(33)
> >
> > u32 fw_dbg_cap;
> >
> > @@ -2185,7 +2186,13 @@ struct bnxt {
> > struct bnxt_tc_info *tc_info;
> > struct list_head tc_indr_block_list;
> > struct dentry *debugfs_pdev;
> > +#ifdef CONFIG_BNXT_HWMON
> > struct device *hwmon_dev;
> > + u8 warn_thresh_temp;
> > + u8 crit_thresh_temp;
> > + u8 fatal_thresh_temp;
> > + u8 shutdown_thresh_temp;
> > +#endif
> > enum board_idx board_idx;
> > };
> >
> > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c
> b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c
> > index 20381b7b1d78..f5affac1169a 100644
> > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c
> > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_hwmon.c
> > @@ -34,6 +34,15 @@ static int bnxt_hwrm_temp_query(struct bnxt *bp, u8
> *temp)
> >
> > if (temp)
> > *temp = resp->temp;
> > +
> > + if (resp->flags &
> TEMP_MONITOR_QUERY_RESP_FLAGS_THRESHOLD_VALUES_AVAILABLE) {
> > + if (!temp)
> > + bp->fw_cap |= BNXT_FW_CAP_THRESHOLD_TEMP_SUPPORTED;
>
> The if statement seems unnecessary. If the flag was not set
> during initialization, the limit attributes won't be visible anyway,
> so it doesn't make a difference if it is set now or not.
>
> > + bp->warn_thresh_temp = resp->warn_threshold;
> > + bp->crit_thresh_temp = resp->critical_threshold;
> > + bp->fatal_thresh_temp = resp->fatal_threshold;
> > + bp->shutdown_thresh_temp = resp->shutdown_threshold;
>
> Are those temperatures expected to change during runtime ? If not it might
> make sense to only execute the entire if condition if temp == NULL to
> avoid unnecessary reassignments whenever the temperature is read.
>
> > + }
> > err:
> > hwrm_req_drop(bp, req);
> > return rc;
> > @@ -42,12 +51,30 @@ static int bnxt_hwrm_temp_query(struct bnxt *bp, u8
> *temp)
> > static umode_t bnxt_hwmon_is_visible(const void *_data, enum
> hwmon_sensor_types type,
> > u32 attr, int channel)
> > {
> > + const struct bnxt *bp = _data;
> > +
> > if (type != hwmon_temp)
> > return 0;
> >
> > switch (attr) {
> > case hwmon_temp_input:
> > return 0444;
> > + case hwmon_temp_lcrit:
> > + case hwmon_temp_crit:
> > + case hwmon_temp_emergency:
> > + case hwmon_temp_lcrit_alarm:
> > + case hwmon_temp_crit_alarm:
> > + case hwmon_temp_emergency_alarm:
> > + if (~bp->fw_cap & BNXT_FW_CAP_THRESHOLD_TEMP_SUPPORTED)
>
> Seems to me that
> if (!(bp->fw_cap & BNXT_FW_CAP_THRESHOLD_TEMP_SUPPORTED))
> would be much easier to understand.
>
> > + return 0;
> > + return 0444;
> > + /* Max temperature setting in NVM is optional */
> > + case hwmon_temp_max:
> > + case hwmon_temp_max_alarm:
> > + if (~bp->fw_cap & BNXT_FW_CAP_THRESHOLD_TEMP_SUPPORTED ||
> > + !bp->shutdown_thresh_temp)
> > + return 0;
>
> Wrong use of the 'max' attribute. More on that below.
>
> > + return 0444;
> > default:
> > return 0;
> > }
> > @@ -66,6 +93,38 @@ static int bnxt_hwmon_read(struct device *dev, enum
> hwmon_sensor_types type, u32
> > if (!rc)
> > *val = temp * 1000;
> > return rc;
> > + case hwmon_temp_lcrit:
> > + *val = bp->warn_thresh_temp * 1000;
> > + return 0;
> > + case hwmon_temp_crit:
> > + *val = bp->crit_thresh_temp * 1000;
> > + return 0;
> > + case hwmon_temp_emergency:
> > + *val = bp->fatal_thresh_temp * 1000;
> > + return 0;
> > + case hwmon_temp_max:
> > + *val = bp->shutdown_thresh_temp * 1000;
> > + return 0;
> > + case hwmon_temp_lcrit_alarm:
> > + rc = bnxt_hwrm_temp_query(bp, &temp);
> > + if (!rc)
> > + *val = temp >= bp->warn_thresh_temp;
>
> That is wrong. lcrit is the _lower_ critical temperature, ie the
> temperature is critically low. This is not a "high temperature"
> alarm.
>
> > + return rc;
> > + case hwmon_temp_crit_alarm:
> > + rc = bnxt_hwrm_temp_query(bp, &temp);
> > + if (!rc)
> > + *val = temp >= bp->crit_thresh_temp;
> > + return rc;
> > + case hwmon_temp_emergency_alarm:
> > + rc = bnxt_hwrm_temp_query(bp, &temp);
> > + if (!rc)
> > + *val = temp >= bp->fatal_thresh_temp;
> > + return rc;
> > + case hwmon_temp_max_alarm:
> > + rc = bnxt_hwrm_temp_query(bp, &temp);
> > + if (!rc)
> > + *val = temp >= bp->shutdown_thresh_temp;
>
> Hmm, that isn't really the purpose of alarm attributes. The expectation
> would be that the chip sets alarm flags and the driver reports it.
> I guess there is some value in having it, so I won't object.
>
> Anyway, the ordering is wrong. max_alarm should be the lowest
> alarm level, followed by crit and emergency. So
> max_alarm -> temp >= bp->warn_thresh_temp
> crit_alarm -> temp >= bp->crit_thresh_temp
> emergency_alarm -> temp >= bp->fatal_thresh_temp
> or temp >= bp->shutdown_thresh_temp
>
> There are only three levels of upper temperature alarms.
> Abusing lcrit as 4th upper alarm is most definitely wrong.
>
[Kalesh]: Thank you for the clarification.
bnxt_en driver wants to expose 4 threshold temperatures to the user through
hwmon sysfs.
1. warning threshold temperature
2. critical threshold temperature
3. fatal threshold temperature
4. shutdown threshold temperature
I will use the following mapping:
hwmon_temp_max : warning threshold temperature
hwmon_temp_crit : critical threshold temperature
hwmon_temp_emergency : fatal threshold temperature
hwmon_temp_max_alarm : temp >= bp->warn_thresh_temp
hwmon_temp_crit_alarm : temp >= bp->crit_thresh_temp
hwmon_temp_emergency_alarm : temp >= bp->fatal_thresh_temp
Is it OK to map the shutdown threshold temperature to "hwmon_temp_fault"?
If not, can you please suggest an alternative?
Regards,
Kalesh
>
> > + return rc;
> > default:
> > return -EOPNOTSUPP;
> > }
> > @@ -73,7 +132,11 @@ static int bnxt_hwmon_read(struct device *dev, enum
> hwmon_sensor_types type, u32
> >
> > static const struct hwmon_channel_info *bnxt_hwmon_info[] = {
> > HWMON_CHANNEL_INFO(temp,
> > - HWMON_T_INPUT),
> > + HWMON_T_INPUT |
> > + HWMON_T_MAX | HWMON_T_LCRIT |
> > + HWMON_T_CRIT | HWMON_T_EMERGENCY |
> > + HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
> > + HWMON_T_MAX_ALARM | HWMON_T_EMERGENCY_ALARM),
> > NULL
> > };
> >
> > @@ -97,13 +160,11 @@ void bnxt_hwmon_uninit(struct bnxt *bp)
> >
> > void bnxt_hwmon_init(struct bnxt *bp)
> > {
> > - struct hwrm_temp_monitor_query_input *req;
> > struct pci_dev *pdev = bp->pdev;
> > int rc;
> >
> > - rc = hwrm_req_init(bp, req, HWRM_TEMP_MONITOR_QUERY);
> > - if (!rc)
> > - rc = hwrm_req_send_silent(bp, req);
> > + /* temp1_xxx is only sensor, ensure not registered if it will fail
> */
> > + rc = bnxt_hwrm_temp_query(bp, NULL);
>
> Ah, that is the reason for the check in bnxt_hwrm_temp_query().
> The check in that function should really be added here, not in the
> previous patch.
>
> > if (rc == -EACCES || rc == -EOPNOTSUPP) {
> > bnxt_hwmon_uninit(bp);
> > return;
> > --
> > 2.30.1
> >
>
>
>
--
Regards,
Kalesh A P
Content of type "text/html" skipped
Download attachment "smime.p7s" of type "application/pkcs7-signature" (4239 bytes)
Powered by blists - more mailing lists