Fix buffer overflow in trans_stat_show().
Convert simple snprintf to the more secure scnprintf with size of
PAGE_SIZE.
Add condition checking if we are exceeding PAGE_SIZE and exit early from
loop. Also add at the end a warning that we exceeded PAGE_SIZE and that
stats is disabled.
Return -EFBIG in the case where we don't have enough space to write the
full transition table.
Also document in the ABI that this function can return -EFBIG error.
Link: https://lore.kernel.org/all/20231024183016.14648-2-ansuelsmth@gmail.com/
Cc: stable@vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218041
Fixes: e552bbaf5b ("PM / devfreq: Add sysfs node for representing frequency transition information.")
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
srcu_init_notifier_head() allocates resources that need to be released
with a srcu_cleanup_notifier_head() call.
Reported by kmemleak.
Fixes: 0fe3a66410 ("PM / devfreq: Add new DEVFREQ_TRANSITION_NOTIFIER notifier")
Cc: <stable@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Current kernel-doc comment doesn't specify the default timer used for the
load monitoring. Also, it uses the term "default delayed work" which could
be misunderstood as "default delayer timer". So reword the comment to
clearly specify the default timer and also reword the last sentence to make
it more understandable.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The member void *data in the structure devfreq can be overwrite
by governor_userspace. For example:
1. The device driver assigned the devfreq governor to simple_ondemand
by the function devfreq_add_device() and init the devfreq member
void *data to a pointer of a static structure devfreq_simple_ondemand_data
by the function devfreq_add_device().
2. The user changed the devfreq governor to userspace by the command
"echo userspace > /sys/class/devfreq/.../governor".
3. The governor userspace alloced a dynamic memory for the struct
userspace_data and assigend the member void *data of devfreq to
this memory by the function userspace_init().
4. The user changed the devfreq governor back to simple_ondemand
by the command "echo simple_ondemand > /sys/class/devfreq/.../governor".
5. The governor userspace exited and assigned the member void *data
in the structure devfreq to NULL by the function userspace_exit().
6. The governor simple_ondemand fetched the static information of
devfreq_simple_ondemand_data in the function
devfreq_simple_ondemand_func() but the member void *data of devfreq was
assigned to NULL by the function userspace_exit().
7. The information of upthreshold and downdifferential is lost
and the governor simple_ondemand can't work correctly.
The member void *data in the structure devfreq is designed for
a static pointer used in a governor and inited by the function
devfreq_add_device(). This patch add an element named governor_data
in the devfreq structure which can be used by a governor(E.g userspace)
who want to assign a private data to do some private things.
Fixes: ce26c5bb95 ("PM / devfreq: Add basic governors")
Cc: stable@vger.kernel.org # 5.10+
Reviewed-by: Chanwoo Choi <cwchoi00@gmail.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kant Fan <kant@allwinnertech.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
There are 4 warnings there:
drivers/devfreq/devfreq.c:707: warning: Function parameter or member 'val' not described in 'qos_min_notifier_call'
drivers/devfreq/devfreq.c:707: warning: Function parameter or member 'ptr' not described in 'qos_min_notifier_call'
drivers/devfreq/devfreq.c:717: warning: Function parameter or member 'val' not described in 'qos_max_notifier_call'
drivers/devfreq/devfreq.c:717: warning: Function parameter or member 'ptr' not described in 'qos_max_notifier_call'
It turns that neither val nor ptr are actually used on those
function, so document as such.
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
On a devfreq PROBE_DEFER, the freq_table in the driver profile struct,
is never reset and may be leaved in an undefined state.
This comes from the fact that we store the freq_table in the driver
profile struct that is commonly defined as static and not reset on
PROBE_DEFER.
We currently skip the reinit of the freq_table if we found
it's already defined since a driver may declare his own freq_table.
This logic is flawed in the case devfreq core generate a freq_table, set
it in the profile struct and then PROBE_DEFER, freeing the freq_table.
In this case devfreq will found a NOT NULL freq_table that has been
freed, skip the freq_table generation and probe the driver based on the
wrong table.
To fix this and correctly handle PROBE_DEFER, use a local freq_table and
max_state in the devfreq struct and never modify the freq_table present
in the profile struct if it does provide it.
Fixes: 0ec09ac2ce ("PM / devfreq: Set the freq_table of devfreq device")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Don't print warning when a governor PROBE_DEFER as it's not a real
GOV_START fail.
Fixes: a03dacb031 ("PM / devfreq: Add cpu based scaling support to passive governor")
Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Suppose devfreq_update_status() failure in devfreq_set_target() is not a
critical error, reduces the log severity.
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Since commit ea572f8160 ("PM / devfreq: Change return type of
devfreq_set_freq_table()"), all devfreq devices are expected to have a
valid freq_table. The devfreq core unconditionally dereferences
freq_table in the sysfs code and in get_freq_range().
Therefore, we need to ensure that freq_table is both non-null and
non-empty (length is > 0). If either check fails, replace the table
using set_freq_table() or return the error.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Set err code in the error path before jumping to the end of the function.
Fixes: 4dc3bab868 ("PM / devfreq: Add support delayed timer for polling mode")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Use the more accurate returned new_freq as resume_freq.
It's the same as how devfreq->previous_freq was updated.
Fixes: 83f8ca45af ("PM / devfreq: add support for suspend/resume of a devfreq device")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The devfreq->lock is held for time of setup. Release the lock in the
error path, before jumping to the end of the function.
Change the goto destination which frees the allocated memory.
Cc: v5.9+ <stable@vger.kernel.org> # v5.9+
Fixes: 4dc3bab868 ("PM / devfreq: Add support delayed timer for polling mode")
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Currently the default behavior is to manually having the devfreq
backend to register themselves as a devfreq cooling device.
Instead of adding the code in the drivers for the thermal cooling
device registering, let's provide a flag in the devfreq's profile to
tell the common devfreq code to register the newly created devfreq as
a cooling device.
Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
* pm-devfreq:
PM / devfreq: rk3399_dmc: Remove unneeded semicolon
PM / devfreq: Replace devfreq->dev.parent as dev in devfreq_add_device
PM / devfreq: Correct spelling in a comment
* pm-tools:
cpupower: Add cpuid cap flag for MSR_AMD_HWCR support
cpupower: Remove family arg to decode_pstates()
cpupower: Condense pstate enabled bit checks in decode_pstates()
cpupower: Update family checks when decoding HW pstates
cpupower: Remove unused pscur variable.
cpupower: Add CPUPOWER_CAP_AMD_HW_PSTATE cpuid caps flag
cpupower: Correct macro name for CPB caps flag
cpupower: Update msr_pstate union struct naming
cpupower: add Makefile dependencies for install targets
In devfreq_add_device, replace devfreq->dev.parent
as dev to keep code simple.
Signed-off-by: pierre Kuo <vichy.kuo@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
