Re: [PATCH] cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier
From: Daniel Axtens <hidden>
Date: 2020-09-24 02:37:05
Hi Srikar,
The patch avoids allocating cpufreq_policy on stack hence fixing frame size overflow in 'powernv_cpufreq_reboot_notifier' ./drivers/cpufreq/powernv-cpufreq.c: In function _powernv_cpufreq_reboot_notifier_: ./drivers/cpufreq/powernv-cpufreq.c:906:1: error: the frame size of 2064 bytes is larger than 2048 bytes [-Werror=frame-larger-than=] } ^ cc1: all warnings being treated as errors make[3]: *** [./scripts/Makefile.build:316: drivers/cpufreq/powernv-cpufreq.o] Error 1 make[2]: *** [./scripts/Makefile.build:556: drivers/cpufreq] Error 2 make[1]: *** [./Makefile:1072: drivers] Error 2 make[1]: *** Waiting for unfinished jobs.... make: *** [Makefile:157: sub-make] Error 2
This looks a lot like commit d95fe371ecd2 ("cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_work_fn").
As with that patch, I have checked for matching puts/gets and that all
uses of '&' check out.
I tried to look at the snowpatch tests: they apparently reported a
checkpatch warning but the file has since disappeared so I can't see
what it was. Running checkpatch locally:
$ scripts/checkpatch.pl -g HEAD -strict
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#15:
make[3]: *** [./scripts/Makefile.build:316: drivers/cpufreq/powernv-cpufreq.o] Error 1
This is benign and you shouldn't wrap that line anyway.
On that basis:
Reviewed-by: Daniel Axtens <redacted>
Kind regards,
Daniel
quoted hunk ↗ jump to hunk
Fixes: cf30af76 ("cpufreq: powernv: Set the cpus to nominal frequency during reboot/kexec") Cc: Pratik Rajesh Sampat <redacted> Cc: Daniel Axtens <redacted> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linuxppc-dev <redacted> Signed-off-by: Srikar Dronamraju <redacted> --- drivers/cpufreq/powernv-cpufreq.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index a9af15e..e439b43 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c@@ -885,12 +885,15 @@ static int powernv_cpufreq_reboot_notifier(struct notifier_block *nb, unsigned long action, void *unused) { int cpu; - struct cpufreq_policy cpu_policy; + struct cpufreq_policy *cpu_policy; rebooting = true; for_each_online_cpu(cpu) { - cpufreq_get_policy(&cpu_policy, cpu); - powernv_cpufreq_target_index(&cpu_policy, get_nominal_index()); + cpu_policy = cpufreq_cpu_get(cpu); + if (!cpu_policy) + continue; + powernv_cpufreq_target_index(cpu_policy, get_nominal_index()); + cpufreq_cpu_put(cpu_policy); } return NOTIFY_DONE;-- 1.8.3.1