Re: [PATCH v2 0/4] Fix some errors in the devfreq core layer when governor is NULL
From: Yaxiong Tian
Date: Mon Apr 27 2026 - 23:00:21 EST
在 2026/4/28 10:50, Jie Zhan 写道:
No plans for now. I tried using BT4 and found that it can automatically extract your tags. Currently, we only have some disagreements on patch 4. This patch isn't very important and can be ignored. Let's just wait for the maintainers to decide—maybe your solution or someone else's will be better.
On 4/1/2026 11:28 AM, Yaxiong Tian wrote:
While doing some development work with devfreq_add_governor()/Hi Yaxiong,
devfreq_remove_governor(), I discovered several bugs caused when
devfreq->governor is NULL. Specifically:
1) A possible null pointer issue in devfreq_add_governor(), caused
by devfreq_remove_governor() setting devfreq->governor to NULL in
certain situations, while devfreq_add_governor() lacks corresponding
checks for devfreq->governor.
2) When operating on governor and available_governors under /sys,
there are also some unexpected errors.
For issue 1, the solution is similar to Jie Zhan's PATCH.
https://lore.kernel.org/linux-pm/20260326123428.800407-6-zhanjie9@xxxxxxxxxxxxx/
The original v1 approach actually changed the original logic, which is incorrect.
See the following patches for details.
change in v2:
1) rebase to linux-next(20260326) /devfreq-next
2) remove some code to fix null pointer in patch1
3) add sysfs_update_group() in patch2
Yaxiong Tian (4):
PM / devfreq: Fix possible null pointer issue in
devfreq_add_governor()
PM / devfreq: Fix available_governors_show() when no governor is set
PM / devfreq: Fix governor_store() failing when device has no current
governor
PM / devfreq: Optimize error return value of governor_show()
drivers/devfreq/devfreq.c | 57 +++++++++++----------------------------
1 file changed, 16 insertions(+), 41 deletions(-)
Any plan for updating this in the 7.1 cycle?
Jie