From d98ccfc3948ab63152494bb6b9c17e15295c0310 Mon Sep 17 00:00:00 2001 From: Dave Gerlach Date: Tue, 13 Nov 2018 13:30:40 -0600 Subject: cpufreq: ti-cpufreq: Only register platform_device when supported Currently the ti-cpufreq driver blindly registers a 'ti-cpufreq' to force the driver to probe on any platforms where the driver is built in. However, this should only happen on platforms that actually can make use of the driver. There is already functionality in place to match the SoC compatible so let's factor this out into a separate call and make sure we find a match before creating the ti-cpufreq platform device. Reviewed-by: Johan Hovold Signed-off-by: Dave Gerlach Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/ti-cpufreq.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/ti-cpufreq.c b/drivers/cpufreq/ti-cpufreq.c index 3f0e2a14895a..22b53bf26817 100644 --- a/drivers/cpufreq/ti-cpufreq.c +++ b/drivers/cpufreq/ti-cpufreq.c @@ -201,19 +201,28 @@ static const struct of_device_id ti_cpufreq_of_match[] = { {}, }; +static const struct of_device_id *ti_cpufreq_match_node(void) +{ + struct device_node *np; + const struct of_device_id *match; + + np = of_find_node_by_path("/"); + match = of_match_node(ti_cpufreq_of_match, np); + of_node_put(np); + + return match; +} + static int ti_cpufreq_probe(struct platform_device *pdev) { u32 version[VERSION_COUNT]; - struct device_node *np; const struct of_device_id *match; struct opp_table *ti_opp_table; struct ti_cpufreq_data *opp_data; const char * const reg_names[] = {"vdd", "vbb"}; int ret; - np = of_find_node_by_path("/"); - match = of_match_node(ti_cpufreq_of_match, np); - of_node_put(np); + match = dev_get_platdata(&pdev->dev); if (!match) return -ENODEV; @@ -290,7 +299,14 @@ fail_put_node: static int ti_cpufreq_init(void) { - platform_device_register_simple("ti-cpufreq", -1, NULL, 0); + const struct of_device_id *match; + + /* Check to ensure we are on a compatible platform */ + match = ti_cpufreq_match_node(); + if (match) + platform_device_register_data(NULL, "ti-cpufreq", -1, match, + sizeof(*match)); + return 0; } module_init(ti_cpufreq_init); -- cgit v1.2.3-58-ga151 From c22397888f1eed98cd59f0a88f2a5f6925f80e15 Mon Sep 17 00:00:00 2001 From: Chanho Min Date: Mon, 12 Nov 2018 12:54:45 +0900 Subject: exec: make de_thread() freezable Suspend fails due to the exec family of functions blocking the freezer. The casue is that de_thread() sleeps in TASK_UNINTERRUPTIBLE waiting for all sub-threads to die, and we have the deadlock if one of them is frozen. This also can occur with the schedule() waiting for the group thread leader to exit if it is frozen. In our machine, it causes freeze timeout as bellows. Freezing of tasks failed after 20.010 seconds (1 tasks refusing to freeze, wq_busy=0): setcpushares-ls D ffffffc00008ed70 0 5817 1483 0x0040000d Call trace: [] __switch_to+0x88/0xa0 [] __schedule+0x1bc/0x720 [] schedule+0x40/0xa8 [] flush_old_exec+0xdc/0x640 [] load_elf_binary+0x2a8/0x1090 [] search_binary_handler+0x9c/0x240 [] load_script+0x20c/0x228 [] search_binary_handler+0x9c/0x240 [] do_execveat_common.isra.14+0x4f8/0x6e8 [] compat_SyS_execve+0x38/0x48 [] el0_svc_naked+0x24/0x28 To fix this, make de_thread() freezable. It looks safe and works fine. Suggested-by: Oleg Nesterov Signed-off-by: Chanho Min Acked-by: Oleg Nesterov Acked-by: Pavel Machek Acked-by: Michal Hocko Signed-off-by: Rafael J. Wysocki --- fs/exec.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index fc281b738a98..acc3a5536384 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -62,6 +62,7 @@ #include #include #include +#include #include #include @@ -1083,7 +1084,7 @@ static int de_thread(struct task_struct *tsk) while (sig->notify_count) { __set_current_state(TASK_KILLABLE); spin_unlock_irq(lock); - schedule(); + freezable_schedule(); if (unlikely(__fatal_signal_pending(tsk))) goto killed; spin_lock_irq(lock); @@ -1111,7 +1112,7 @@ static int de_thread(struct task_struct *tsk) __set_current_state(TASK_KILLABLE); write_unlock_irq(&tasklist_lock); cgroup_threadgroup_change_end(tsk); - schedule(); + freezable_schedule(); if (unlikely(__fatal_signal_pending(tsk))) goto killed; } -- cgit v1.2.3-58-ga151