| From 4824586a139df271c047bee204a02f9d49a135fc Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 5 Aug 2021 15:29:17 +0800 |
| Subject: cpufreq: schedutil: Use kobject release() method to free |
| sugov_tunables |
| |
| From: Kevin Hao <haokexin@gmail.com> |
| |
| [ Upstream commit e5c6b312ce3cc97e90ea159446e6bfa06645364d ] |
| |
| The struct sugov_tunables is protected by the kobject, so we can't free |
| it directly. Otherwise we would get a call trace like this: |
| ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x30 |
| WARNING: CPU: 3 PID: 720 at lib/debugobjects.c:505 debug_print_object+0xb8/0x100 |
| Modules linked in: |
| CPU: 3 PID: 720 Comm: a.sh Tainted: G W 5.14.0-rc1-next-20210715-yocto-standard+ #507 |
| Hardware name: Marvell OcteonTX CN96XX board (DT) |
| pstate: 40400009 (nZcv daif +PAN -UAO -TCO BTYPE=--) |
| pc : debug_print_object+0xb8/0x100 |
| lr : debug_print_object+0xb8/0x100 |
| sp : ffff80001ecaf910 |
| x29: ffff80001ecaf910 x28: ffff00011b10b8d0 x27: ffff800011043d80 |
| x26: ffff00011a8f0000 x25: ffff800013cb3ff0 x24: 0000000000000000 |
| x23: ffff80001142aa68 x22: ffff800011043d80 x21: ffff00010de46f20 |
| x20: ffff800013c0c520 x19: ffff800011d8f5b0 x18: 0000000000000010 |
| x17: 6e6968207473696c x16: 5f72656d6974203a x15: 6570797420746365 |
| x14: 6a626f2029302065 x13: 303378302f307830 x12: 2b6e665f72656d69 |
| x11: ffff8000124b1560 x10: ffff800012331520 x9 : ffff8000100ca6b0 |
| x8 : 000000000017ffe8 x7 : c0000000fffeffff x6 : 0000000000000001 |
| x5 : ffff800011d8c000 x4 : ffff800011d8c740 x3 : 0000000000000000 |
| x2 : ffff0001108301c0 x1 : ab3c90eedf9c0f00 x0 : 0000000000000000 |
| Call trace: |
| debug_print_object+0xb8/0x100 |
| __debug_check_no_obj_freed+0x1c0/0x230 |
| debug_check_no_obj_freed+0x20/0x88 |
| slab_free_freelist_hook+0x154/0x1c8 |
| kfree+0x114/0x5d0 |
| sugov_exit+0xbc/0xc0 |
| cpufreq_exit_governor+0x44/0x90 |
| cpufreq_set_policy+0x268/0x4a8 |
| store_scaling_governor+0xe0/0x128 |
| store+0xc0/0xf0 |
| sysfs_kf_write+0x54/0x80 |
| kernfs_fop_write_iter+0x128/0x1c0 |
| new_sync_write+0xf0/0x190 |
| vfs_write+0x2d4/0x478 |
| ksys_write+0x74/0x100 |
| __arm64_sys_write+0x24/0x30 |
| invoke_syscall.constprop.0+0x54/0xe0 |
| do_el0_svc+0x64/0x158 |
| el0_svc+0x2c/0xb0 |
| el0t_64_sync_handler+0xb0/0xb8 |
| el0t_64_sync+0x198/0x19c |
| irq event stamp: 5518 |
| hardirqs last enabled at (5517): [<ffff8000100cbd7c>] console_unlock+0x554/0x6c8 |
| hardirqs last disabled at (5518): [<ffff800010fc0638>] el1_dbg+0x28/0xa0 |
| softirqs last enabled at (5504): [<ffff8000100106e0>] __do_softirq+0x4d0/0x6c0 |
| softirqs last disabled at (5483): [<ffff800010049548>] irq_exit+0x1b0/0x1b8 |
| |
| So split the original sugov_tunables_free() into two functions, |
| sugov_clear_global_tunables() is just used to clear the global_tunables |
| and the new sugov_tunables_free() is used as kobj_type::release to |
| release the sugov_tunables safely. |
| |
| Fixes: 9bdcb44e391d ("cpufreq: schedutil: New governor based on scheduler utilization data") |
| Cc: 4.7+ <stable@vger.kernel.org> # 4.7+ |
| Signed-off-by: Kevin Hao <haokexin@gmail.com> |
| Acked-by: Viresh Kumar <viresh.kumar@linaro.org> |
| Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| kernel/sched/cpufreq_schedutil.c | 16 +++++++++++----- |
| 1 file changed, 11 insertions(+), 5 deletions(-) |
| |
| diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c |
| index 97d318b0cd0c..5e39da0ae086 100644 |
| --- a/kernel/sched/cpufreq_schedutil.c |
| +++ b/kernel/sched/cpufreq_schedutil.c |
| @@ -610,9 +610,17 @@ static struct attribute *sugov_attrs[] = { |
| }; |
| ATTRIBUTE_GROUPS(sugov); |
| |
| +static void sugov_tunables_free(struct kobject *kobj) |
| +{ |
| + struct gov_attr_set *attr_set = container_of(kobj, struct gov_attr_set, kobj); |
| + |
| + kfree(to_sugov_tunables(attr_set)); |
| +} |
| + |
| static struct kobj_type sugov_tunables_ktype = { |
| .default_groups = sugov_groups, |
| .sysfs_ops = &governor_sysfs_ops, |
| + .release = &sugov_tunables_free, |
| }; |
| |
| /********************** cpufreq governor interface *********************/ |
| @@ -712,12 +720,10 @@ static struct sugov_tunables *sugov_tunables_alloc(struct sugov_policy *sg_polic |
| return tunables; |
| } |
| |
| -static void sugov_tunables_free(struct sugov_tunables *tunables) |
| +static void sugov_clear_global_tunables(void) |
| { |
| if (!have_governor_per_policy()) |
| global_tunables = NULL; |
| - |
| - kfree(tunables); |
| } |
| |
| static int sugov_init(struct cpufreq_policy *policy) |
| @@ -780,7 +786,7 @@ out: |
| fail: |
| kobject_put(&tunables->attr_set.kobj); |
| policy->governor_data = NULL; |
| - sugov_tunables_free(tunables); |
| + sugov_clear_global_tunables(); |
| |
| stop_kthread: |
| sugov_kthread_stop(sg_policy); |
| @@ -807,7 +813,7 @@ static void sugov_exit(struct cpufreq_policy *policy) |
| count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook); |
| policy->governor_data = NULL; |
| if (!count) |
| - sugov_tunables_free(tunables); |
| + sugov_clear_global_tunables(); |
| |
| mutex_unlock(&global_tunables_lock); |
| |
| -- |
| 2.33.0 |
| |