cpufreq: governor: Use kobject release() method to free dbs_data
The struct dbs_data embeds a struct gov_attr_set and
the struct gov_attr_set embeds a kobject. Since every kobject must have
a release() method and we can't use kfree() to free it directly,
so introduce cpufreq_dbs_data_release() to release the dbs_data via
the kobject::release() method. This fixes the calltrace like below:
ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x34
WARNING: CPU: 12 PID: 810 at lib/debugobjects.c:505 debug_print_object+0xb8/0x100
Modules linked in:
CPU: 12 PID: 810 Comm: sh Not tainted 5.16.0-next-
20220120-yocto-standard+ #536
Hardware name: Marvell OcteonTX CN96XX board (DT)
pstate:
60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : debug_print_object+0xb8/0x100
lr : debug_print_object+0xb8/0x100
sp :
ffff80001dfcf9a0
x29:
ffff80001dfcf9a0 x28:
0000000000000001 x27:
ffff0001464f0000
x26:
0000000000000000 x25:
ffff8000090e3f00 x24:
ffff80000af60210
x23:
ffff8000094dfb78 x22:
ffff8000090e3f00 x21:
ffff0001080b7118
x20:
ffff80000aeb2430 x19:
ffff800009e8f5e0 x18:
0000000000000000
x17:
0000000000000002 x16:
00004d62e58be040 x15:
013590470523aff8
x14:
ffff8000090e1828 x13:
0000000001359047 x12:
00000000f5257d14
x11:
0000000000040591 x10:
0000000066c1ffea x9 :
ffff8000080d15e0
x8 :
ffff80000a1765a8 x7 :
0000000000000000 x6 :
0000000000000001
x5 :
ffff800009e8c000 x4 :
ffff800009e8c760 x3 :
0000000000000000
x2 :
0000000000000000 x1 :
0000000000000000 x0 :
ffff0001474ed040
Call trace:
debug_print_object+0xb8/0x100
__debug_check_no_obj_freed+0x1d0/0x25c
debug_check_no_obj_freed+0x24/0xa0
kfree+0x11c/0x440
cpufreq_dbs_governor_exit+0xa8/0xac
cpufreq_exit_governor+0x44/0x90
cpufreq_set_policy+0x29c/0x570
store_scaling_governor+0x110/0x154
store+0xb0/0xe0
sysfs_kf_write+0x58/0x84
kernfs_fop_write_iter+0x12c/0x1c0
new_sync_write+0xf0/0x18c
vfs_write+0x1cc/0x220
ksys_write+0x74/0x100
__arm64_sys_write+0x28/0x3c
invoke_syscall.constprop.0+0x58/0xf0
do_el0_svc+0x70/0x170
el0_svc+0x54/0x190
el0t_64_sync_handler+0xa4/0x130
el0t_64_sync+0x1a0/0x1a4
irq event stamp: 189006
hardirqs last enabled at (189005): [<
ffff8000080849d0>] finish_task_switch.isra.0+0xe0/0x2c0
hardirqs last disabled at (189006): [<
ffff8000090667a4>] el1_dbg+0x24/0xa0
softirqs last enabled at (188966): [<
ffff8000080106d0>] __do_softirq+0x4b0/0x6a0
softirqs last disabled at (188957): [<
ffff80000804a618>] __irq_exit_rcu+0x108/0x1a4
[ rjw: Because can be freed by the gov_attr_set_put() in
cpufreq_dbs_governor_exit() now, it is also necessary to put the
invocation of the governor ->exit() callback into the new
cpufreq_dbs_data_release() function. ]
Fixes: c4435630361d ("cpufreq: governor: New sysfs show/store callbacks for governor tunables")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>