kernel/linux.git/drivers/devfreq, branch v6.6.132

PM / devfreq: mtk-cci: Fix potential error pointer dereference in probe()

2025-10-15T09:57:51+00:00

[ Upstream commit fc33bf0e097c6834646b98a7b3da0ae5b617f0f9 ] The drv->sram_reg pointer could be set to ERR_PTR(-EPROBE_DEFER) which would lead to a error pointer dereference. Use IS_ERR_OR_NULL() to check that the pointer is valid. Fixes: e09bd5757b52 ("PM / devfreq: mtk-cci: Handle sram regulator probe deferral") Signed-off-by: Dan Carpenter Signed-off-by: Chanwoo Choi Link: https://patchwork.kernel.org/project/linux-pm/patch/aJTNHz8kk8s6Q2os@stanley.mountain/ Signed-off-by: Sasha Levin

PM / devfreq: governor: Replace sscanf() with kstrtoul() in set_freq_store()

2025-08-28T14:28:16+00:00

[ Upstream commit 914cc799b28f17d369d5b4db3b941957d18157e8 ] Replace sscanf() with kstrtoul() in set_freq_store() and check the result to avoid invalid input. Signed-off-by: Lifeng Zheng Link: https://lore.kernel.org/lkml/20250421030020.3108405-2-zhenglifeng1@huawei.com/ Signed-off-by: Chanwoo Choi Signed-off-by: Sasha Levin

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

2025-08-15T10:08:43+00:00

[ Upstream commit bab7834c03820eb11269bc48f07c3800192460d2 ] 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 Signed-off-by: Sasha Levin

PM / devfreq: Synchronize devfreq_monitor_[start/stop]

2024-02-05T20:14:15+00:00

[ Upstream commit aed5ed595960c6d301dcd4ed31aeaa7a8054c0c6 ] 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 Signed-off-by: Sasha Levin

PM / devfreq: Fix buffer overflow in trans_stat_show

2024-02-01T00:18:50+00:00

commit 08e23d05fa6dc4fc13da0ccf09defdd4bbc92ff4 upstream. 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: e552bbaf5b98 ("PM / devfreq: Add sysfs node for representing frequency transition information.") Signed-off-by: Christian Marangi Signed-off-by: Chanwoo Choi Signed-off-by: Greg Kroah-Hartman

PM / devfreq: rockchip-dfi: Make pmu regmap mandatory

2023-11-20T10:59:00+00:00

[ Upstream commit 1e0731c05c985deb68a97fa44c1adcd3305dda90 ] As a matter of fact the regmap_pmu already is mandatory because it is used unconditionally in the driver. Bail out gracefully in probe() rather than crashing later. Link: https://lore.kernel.org/lkml/20230704093242.583575-2-s.hauer@pengutronix.de/ Fixes: b9d1262bca0af ("PM / devfreq: event: support rockchip dfi controller") Reviewed-by: Sebastian Reichel Signed-off-by: Sascha Hauer Signed-off-by: Chanwoo Choi Signed-off-by: Sasha Levin

PM / devfreq: Fix leak in devfreq_dev_release()

2023-08-10T13:48:16+00:00

srcu_init_notifier_head() allocates resources that need to be released with a srcu_cleanup_notifier_head() call. Reported by kmemleak. Fixes: 0fe3a66410a3 ("PM / devfreq: Add new DEVFREQ_TRANSITION_NOTIFIER notifier") Cc: Signed-off-by: Boris Brezillon Reviewed-by: Dhruva Gole Signed-off-by: Chanwoo Choi

PM / devfreq: Reword the kernel-doc comment for devfreq_monitor_start() API

2023-07-23T20:24:36+00:00

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 Signed-off-by: Chanwoo Choi

PM / devfreq: Explicitly include correct DT includes

2023-07-23T20:19:26+00:00

The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring Signed-off-by: Chanwoo Choi

PM / devfreq: mtk-cci: Fix variable deferencing before NULL check

2023-05-29T14:25:31+00:00

smatch warning: drivers/devfreq/mtk-cci-devfreq.c:135 mtk_ccifreq_target() warn: variable dereferenced before check 'drv' (see line 130) This is based on static analysis only. Compilation tested. Signed-off-by: Sukrut Bellary Signed-off-by: Chanwoo Choi