kernel/linux.git/drivers/devfreq/devfreq.c, branch v7.0-rc7

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

PM / devfreq: Move governor.h to a public header location

2025-11-23T15:02:01+00:00

Some device drivers (and out-of-tree modules) might want to define device-specific device governors. Rather than restricting all of them to be a part of drivers/devfreq/ (which is not possible for out-of-tree drivers anyway) move governor.h to include/linux/devfreq-governor.h and update all drivers to use it. The devfreq_cpu_data is only used internally, by the passive governor, so it is moved to the driver source rather than being a part of the public interface. Reported-by: Robie Basak Acked-by: Jon Hunter Signed-off-by: Dmitry Baryshkov Reviewed-by: Bjorn Andersson Acked-by: MyungJoo Ham Signed-off-by: Chanwoo Choi Link: https://patchwork.kernel.org/project/linux-pm/patch/20251030-governor-public-v2-1-432a11a9975a@oss.qualcomm.com/

PM / devfreq: Allow devfreq driver to add custom sysfs ABIs

2025-07-14T11:22:59+00:00

Extend the devfreq_dev_profile to allow drivers optionally create device-specific sysfs ABIs together with other common devfreq ABIs under the devfreq device path. Reviewed-by: Jonathan Cameron Reviewed-by: Huisong Li Signed-off-by: Jie Zhan Signed-off-by: Chanwoo Choi Link: https://patchwork.kernel.org/project/linux-pm/patch/20250623143401.4095045-2-zhanjie9@hisilicon.com/

PM / devfreq: Fix a index typo in trans_stat

2025-07-14T11:04:17+00:00

Fixes: 4920ee6dcfaf ("PM / devfreq: Convert to use sysfs_emit_at() API") Signed-off-by: pls Link: https://patchwork.kernel.org/project/linux-pm/patch/20250515143100.17849-1-chanwoo@kernel.org/ Signed-off-by: Chanwoo Choi

PM / devfreq: Check governor before using governor->name

2025-07-14T11:04:17+00:00

Commit 96ffcdf239de ("PM / devfreq: Remove redundant governor_name from struct devfreq") removes governor_name and uses governor->name to replace it. But devfreq->governor may be NULL and directly using devfreq->governor->name may cause null pointer exception. Move the check of governor to before using governor->name. Fixes: 96ffcdf239de ("PM / devfreq: Remove redundant governor_name from struct devfreq") Signed-off-by: Lifeng Zheng Link: https://lore.kernel.org/lkml/20250421030020.3108405-5-zhenglifeng1@huawei.com/ Signed-off-by: Chanwoo Choi

PM / devfreq: Remove redundant devfreq_get_freq_range() calling in devfreq_add_device()

2025-07-14T11:04:16+00:00

The calling of devfreq_get_freq_range() in devfreq_add_device() is redundant because min_freq and max_freq are never used. Remove it. Signed-off-by: Lifeng Zheng Link: https://lore.kernel.org/lkml/20250421030020.3108405-4-zhenglifeng1@huawei.com/ Signed-off-by: Chanwoo Choi

PM / devfreq: Limit max_freq with scaling_min_freq

2025-07-14T11:04:16+00:00

Limit max_freq in devfreq_get_freq_range() with scaling_min_freq to avoid showing an unreachable freq when reading it. Use macro clamp to simplify code. Signed-off-by: Lifeng Zheng Link: https://lore.kernel.org/lkml/20250421030020.3108405-3-zhenglifeng1@huawei.com/ Signed-off-by: Chanwoo Choi

PM / devfreq: Synchronize devfreq_monitor_[start/stop]

2023-12-18T22:58:27+00:00

There is a chance if a frequent switch of the governor done in a loop result in timer list corruption where timer cancel being done from two place one from cancel_delayed_work_sync() and followed by expire_timers() can be seen from the traces[1]. while true do echo "simple_ondemand" > /sys/class/devfreq/1d84000.ufshc/governor echo "performance" > /sys/class/devfreq/1d84000.ufshc/governor done It looks to be issue with devfreq driver where device_monitor_[start/stop] need to synchronized so that delayed work should get corrupted while it is either being queued or running or being cancelled. Let's use polling flag and devfreq lock to synchronize the queueing the timer instance twice and work data being corrupted. [1] ... .. -0 [003] 9436.209662: timer_cancel timer=0xffffff80444f0428 -0 [003] 9436.209664: timer_expire_entry timer=0xffffff80444f0428 now=0x10022da1c function=__typeid__ZTSFvP10timer_listE_global_addr baseclk=0x10022da1c -0 [003] 9436.209718: timer_expire_exit timer=0xffffff80444f0428 kworker/u16:6-14217 [003] 9436.209863: timer_start timer=0xffffff80444f0428 function=__typeid__ZTSFvP10timer_listE_global_addr expires=0x10022da2b now=0x10022da1c flags=182452227 vendor.xxxyyy.ha-1593 [004] 9436.209888: timer_cancel timer=0xffffff80444f0428 vendor.xxxyyy.ha-1593 [004] 9436.216390: timer_init timer=0xffffff80444f0428 vendor.xxxyyy.ha-1593 [004] 9436.216392: timer_start timer=0xffffff80444f0428 function=__typeid__ZTSFvP10timer_listE_global_addr expires=0x10022da2c now=0x10022da1d flags=186646532 vendor.xxxyyy.ha-1593 [005] 9436.220992: timer_cancel timer=0xffffff80444f0428 xxxyyyTraceManag-7795 [004] 9436.261641: timer_cancel timer=0xffffff80444f0428 [2] 9436.261653][ C4] Unable to handle kernel paging request at virtual address dead00000000012a [ 9436.261664][ C4] Mem abort info: [ 9436.261666][ C4] ESR = 0x96000044 [ 9436.261669][ C4] EC = 0x25: DABT (current EL), IL = 32 bits [ 9436.261671][ C4] SET = 0, FnV = 0 [ 9436.261673][ C4] EA = 0, S1PTW = 0 [ 9436.261675][ C4] Data abort info: [ 9436.261677][ C4] ISV = 0, ISS = 0x00000044 [ 9436.261680][ C4] CM = 0, WnR = 1 [ 9436.261682][ C4] [dead00000000012a] address between user and kernel address ranges [ 9436.261685][ C4] Internal error: Oops: 96000044 [#1] PREEMPT SMP [ 9436.261701][ C4] Skip md ftrace buffer dump for: 0x3a982d0 ... [ 9436.262138][ C4] CPU: 4 PID: 7795 Comm: TraceManag Tainted: G S W O 5.10.149-android12-9-o-g17f915d29d0c #1 [ 9436.262141][ C4] Hardware name: Qualcomm Technologies, Inc. (DT) [ 9436.262144][ C4] pstate: 22400085 (nzCv daIf +PAN -UAO +TCO BTYPE=--) [ 9436.262161][ C4] pc : expire_timers+0x9c/0x438 [ 9436.262164][ C4] lr : expire_timers+0x2a4/0x438 [ 9436.262168][ C4] sp : ffffffc010023dd0 [ 9436.262171][ C4] x29: ffffffc010023df0 x28: ffffffd0636fdc18 [ 9436.262178][ C4] x27: ffffffd063569dd0 x26: ffffffd063536008 [ 9436.262182][ C4] x25: 0000000000000001 x24: ffffff88f7c69280 [ 9436.262185][ C4] x23: 00000000000000e0 x22: dead000000000122 [ 9436.262188][ C4] x21: 000000010022da29 x20: ffffff8af72b4e80 [ 9436.262191][ C4] x19: ffffffc010023e50 x18: ffffffc010025038 [ 9436.262195][ C4] x17: 0000000000000240 x16: 0000000000000201 [ 9436.262199][ C4] x15: ffffffffffffffff x14: ffffff889f3c3100 [ 9436.262203][ C4] x13: ffffff889f3c3100 x12: 00000000049f56b8 [ 9436.262207][ C4] x11: 00000000049f56b8 x10: 00000000ffffffff [ 9436.262212][ C4] x9 : ffffffc010023e50 x8 : dead000000000122 [ 9436.262216][ C4] x7 : ffffffffffffffff x6 : ffffffc0100239d8 [ 9436.262220][ C4] x5 : 0000000000000000 x4 : 0000000000000101 [ 9436.262223][ C4] x3 : 0000000000000080 x2 : ffffff889edc155c [ 9436.262227][ C4] x1 : ffffff8001005200 x0 : ffffff80444f0428 [ 9436.262232][ C4] Call trace: [ 9436.262236][ C4] expire_timers+0x9c/0x438 [ 9436.262240][ C4] __run_timers+0x1f0/0x330 [ 9436.262245][ C4] run_timer_softirq+0x28/0x58 [ 9436.262255][ C4] efi_header_end+0x168/0x5ec [ 9436.262265][ C4] __irq_exit_rcu+0x108/0x124 [ 9436.262274][ C4] __handle_domain_irq+0x118/0x1e4 [ 9436.262282][ C4] gic_handle_irq.30369+0x6c/0x2bc [ 9436.262286][ C4] el0_irq_naked+0x60/0x6c Link: https://lore.kernel.org/all/1700860318-4025-1-git-send-email-quic_mojha@quicinc.com/ Reported-by: Joyyoung Huang Acked-by: MyungJoo Ham Signed-off-by: Mukesh Ojha Signed-off-by: Chanwoo Choi

PM / devfreq: Convert to use sysfs_emit_at() API

2023-11-13T01:48:49+00:00

Follow the advice of the Documentation/filesystems/sysfs.rst and show() should only use sysfs_emit() or sysfs_emit_at() when formatting the value to be returned to user space. Link: https://lore.kernel.org/all/20231024183016.14648-3-ansuelsmth@gmail.com/ Signed-off-by: Christian Marangi Signed-off-by: Chanwoo Choi