linux-stable.git/drivers/cpufreq/cppc_cpufreq.c, branch linux-6.11.y

cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_power()

2024-12-05T12:53:40+00:00

[ Upstream commit b51eb0874d8170028434fbd259e80b78ed9b8eca ]

cppc_get_cpu_power() return 0 if the policy is NULL. Then in
em_create_perf_table(), the later zero check for power is not valid
as power is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of active_power() first, so if the callback
failed it should tell the core. So return -EINVAL to fix it.

Fixes: a78e72075642 ("cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()")
Signed-off-by: Jinjie Ruan 
Suggested-by: Quentin Perret 
Signed-off-by: Viresh Kumar 
Signed-off-by: Sasha Levin

cpufreq: CPPC: Fix wrong return value in cppc_get_cpu_cost()

2024-12-05T12:53:40+00:00

[ Upstream commit be392aa80f1e5b0b65ccc2a540b9304fefcfe3d8 ]

cppc_get_cpu_cost() return 0 if the policy is NULL. Then in
em_compute_costs(), the later zero check for cost is not valid
as cost is uninitialized. As Quentin pointed out, kernel energy model
core check the return value of get_cost() first, so if the callback
failed it should tell the core. Return -EINVAL to fix it.

Fixes: 1a1374bb8c59 ("cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()")
Reported-by: Dan Carpenter 
Closes: https://lore.kernel.org/all/c4765377-7830-44c2-84fa-706b6e304e10@stanley.mountain/
Signed-off-by: Jinjie Ruan 
Suggested-by: Quentin Perret 
Signed-off-by: Viresh Kumar 
Signed-off-by: Sasha Levin

cpufreq: CPPC: Fix possible null-ptr-deref for cppc_get_cpu_cost()

2024-12-05T12:53:34+00:00

[ Upstream commit 1a1374bb8c5926674973d849feed500bc61ad535 ]

cpufreq_cpu_get_raw() may return NULL if the cpu is not in
policy->cpus cpu mask and it will cause null pointer dereference,
so check NULL for cppc_get_cpu_cost().

Fixes: 740fcdc2c20e ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Jinjie Ruan 
Signed-off-by: Viresh Kumar 
Signed-off-by: Sasha Levin

cpufreq: CPPC: Fix possible null-ptr-deref for cpufreq_cpu_get_raw()

2024-12-05T12:53:34+00:00

[ Upstream commit a78e7207564258db6e373e86294a85f9d646d35a ]

cpufreq_cpu_get_raw() may return NULL if the cpu is not in
policy->cpus cpu mask and it will cause null pointer dereference.

Fixes: 740fcdc2c20e ("cpufreq: CPPC: Register EM based on efficiency class information")
Signed-off-by: Jinjie Ruan 
Signed-off-by: Viresh Kumar 
Signed-off-by: Sasha Levin

cppc_cpufreq: Use desired perf if feedback ctrs are 0 or unchanged

2024-12-05T12:53:29+00:00

[ Upstream commit c47195631960b626058c335aec31f186fa854f97 ]

The CPPC performance feedback counters could be 0 or unchanged when the
target cpu is in a low-power idle state, e.g. power-gated or clock-gated.

When the counters are 0, cppc_cpufreq_get_rate() returns 0 KHz, which makes
cpufreq_online() get a false error and fail to generate a cpufreq policy.

When the counters are unchanged, the existing cppc_perf_from_fbctrs()
returns a cached desired perf, but some platforms may update the real
frequency back to the desired perf reg.

For the above cases in cppc_cpufreq_get_rate(), get the latest desired perf
from the CPPC reg to reflect the frequency because some platforms may
update the actual frequency back there; if failed, use the cached desired
perf.

Fixes: 6a4fec4f6d30 ("cpufreq: cppc: cppc_cpufreq_get_rate() returns zero in all error cases.")
Signed-off-by: Jie Zhan 
Reviewed-by: Zeng Heng 
Reviewed-by: Ionela Voinescu 
Reviewed-by: Huisong Li 
Signed-off-by: Viresh Kumar 
Signed-off-by: Sasha Levin

cpufreq: Make cpufreq_driver->exit() return void

2024-07-09T03:15:30+00:00

The cpufreq core doesn't check the return type of the exit() callback
and there is not much the core can do on failures at that point. Just
drop the returned value and make it return void.

Signed-off-by: Lizhe 
[ Viresh: Reworked the patches to fix all missing changes together. ]
Signed-off-by: Viresh Kumar 
Reviewed-by: AngeloGioacchino Del Regno  # Mediatek
Acked-by: Sudeep Holla  # scpi, scmi, vexpress
Acked-by: Mario Limonciello  # amd
Reviewed-by: Florian Fainelli  # bmips
Acked-by: Rafael J. Wysocki 
Acked-by: Kevin Hilman  # omap

cpufreq/cppc: Don't compare desired_perf in target()

2024-06-13T09:42:57+00:00

There is a corner case where the desired_perf is exactly same as the old
perf, but the actual current freq is not.

This happens during S3 while the cpufreq governor is set to powersave.
During cpufreq resume process, the booting CPU's new_freq obtained via
.get() is the highest frequency, while the policy->cur and
cpu->perf_ctrls.desired_perf are set to the lowest level (powersave
governor). This causes the warning: "CPU frequency out of sync:", and
the cpufreq core sets policy->cur to new_freq.

Then the governor->limits() calls cppc_cpufreq_set_target() to
configures the CPU frequency and returns directly because the
desired_perf converted from target_freq is same as the
cpu->perf_ctrls.desired_perf and both are the lowest_perf.

Since target_freq and policy->cur have been already compared in
__cpufreq_driver_target(), there's no need to compare them again here.

Drop the comparison.

Signed-off-by: Riwen Lu 
[ Viresh: Updated commit message / subject ]
Signed-off-by: Viresh Kumar

cppc_cpufreq: Fix possible null pointer dereference

2024-04-19T06:29:16+00:00

cppc_cpufreq_get_rate() and hisi_cppc_cpufreq_get_rate() can be called from
different places with various parameters. So cpufreq_cpu_get() can return
null as 'policy' in some circumstances.
Fix this bug by adding null return check.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: a28b2bfc099c ("cppc_cpufreq: replace per-cpu data array with a list")
Signed-off-by: Aleksandr Mishin 
Signed-off-by: Viresh Kumar

cpufreq/cppc: Move and rename cppc_cpufreq_{perf_to_khz|khz_to_perf}()

2023-12-23T14:52:35+00:00

Move and rename cppc_cpufreq_perf_to_khz() and cppc_cpufreq_khz_to_perf() to
use them outside cppc_cpufreq in topology_init_cpu_capacity_cppc().

Modify the interface to use struct cppc_perf_caps *caps instead of
struct cppc_cpudata *cpu_data as we only use the fields of cppc_perf_caps.

cppc_cpufreq was converting the lowest and nominal freq from MHz to kHz
before using them. We move this conversion inside cppc_perf_to_khz and
cppc_khz_to_perf to make them generic and usable outside cppc_cpufreq.

No functional change

Signed-off-by: Vincent Guittot 
Signed-off-by: Ingo Molnar 
Tested-by: Pierre Gondois 
Acked-by: Rafael J. Wysocki 
Acked-by: Viresh Kumar 
Link: https://lore.kernel.org/r/20231211104855.558096-6-vincent.guittot@linaro.org

cpufreq: cppc: Set fie_disabled to FIE_DISABLED if fails to create kworker_fie

2023-08-17T08:54:58+00:00

The function cppc_freq_invariance_init() may failed to create
kworker_fie, make it more robust by setting fie_disabled to FIE_DISBALED
to prevent an invalid pointer dereference in kthread_destroy_worker(),
which called from cppc_freq_invariance_exit().

Signed-off-by: Liao Chang 
Signed-off-by: Viresh Kumar