5.15-stable review patch. If anyone has any objections, please let me know.
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From: Xiaoming Ni nixiaoming@huawei.com
[ Upstream commit bbe7a10ed83a5fa0b0ff6161ecdc4e65a0e9c993 ]
The kernel/sysctl.c is a kitchen sink where everyone leaves their dirty dishes, this makes it very difficult to maintain.
To help with this maintenance let's start by moving sysctls to places where they actually belong. The proc sysctl maintainers do not want to know what sysctl knobs you wish to add for your own piece of code, we just care about the core logic.
So move hung_task sysctl interface to hung_task.c and use register_sysctl() to register the sysctl interface.
[mcgrof@kernel.org: commit log refresh and fixed 2-3 0day reported compile issues]
Link: https://lkml.kernel.org/r/20211123202347.818157-4-mcgrof@kernel.org Signed-off-by: Xiaoming Ni nixiaoming@huawei.com Signed-off-by: Luis Chamberlain mcgrof@kernel.org Reviewed-by: Kees Cook keescook@chromium.org Reviewed-by: Petr Mladek pmladek@suse.com Cc: Al Viro viro@zeniv.linux.org.uk Cc: Amir Goldstein amir73il@gmail.com Cc: Andy Shevchenko andriy.shevchenko@linux.intel.com Cc: Benjamin LaHaise bcrl@kvack.org Cc: "Eric W. Biederman" ebiederm@xmission.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Iurii Zaikin yzaikin@google.com Cc: Jan Kara jack@suse.cz Cc: Paul Turner pjt@google.com Cc: Peter Zijlstra peterz@infradead.org Cc: Qing Wang wangqing@vivo.com Cc: Sebastian Reichel sre@kernel.org Cc: Sergey Senozhatsky senozhatsky@chromium.org Cc: Stephen Kitt steve@sk2.org Cc: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Cc: Antti Palosaari crope@iki.fi Cc: Arnd Bergmann arnd@arndb.de Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Clemens Ladisch clemens@ladisch.de Cc: David Airlie airlied@linux.ie Cc: Jani Nikula jani.nikula@linux.intel.com Cc: Joel Becker jlbec@evilplan.org Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Joseph Qi joseph.qi@linux.alibaba.com Cc: Julia Lawall julia.lawall@inria.fr Cc: Lukas Middendorf kernel@tuxforce.de Cc: Mark Fasheh mark@fasheh.com Cc: Phillip Potter phil@philpotter.co.uk Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Douglas Gilbert dgilbert@interlog.com Cc: James E.J. Bottomley jejb@linux.ibm.com Cc: Jani Nikula jani.nikula@intel.com Cc: John Ogness john.ogness@linutronix.de Cc: Martin K. Petersen martin.petersen@oracle.com Cc: "Rafael J. Wysocki" rafael@kernel.org Cc: Steven Rostedt (VMware) rostedt@goodmis.org Cc: Suren Baghdasaryan surenb@google.com Cc: "Theodore Ts'o" tytso@mit.edu Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Stable-dep-of: d727935cad9f ("fs: fix proc_handler for sysctl_nr_open") Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/sched/sysctl.h | 14 +------ kernel/hung_task.c | 81 ++++++++++++++++++++++++++++++++++-- kernel/sysctl.c | 61 --------------------------- 3 files changed, 79 insertions(+), 77 deletions(-)
diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index 304f431178fd9..c19dd5a2c05c6 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -7,20 +7,8 @@ struct ctl_table;
#ifdef CONFIG_DETECT_HUNG_TASK - -#ifdef CONFIG_SMP -extern unsigned int sysctl_hung_task_all_cpu_backtrace; -#else -#define sysctl_hung_task_all_cpu_backtrace 0 -#endif /* CONFIG_SMP */ - -extern int sysctl_hung_task_check_count; -extern unsigned int sysctl_hung_task_panic; +/* used for hung_task and block/ */ extern unsigned long sysctl_hung_task_timeout_secs; -extern unsigned long sysctl_hung_task_check_interval_secs; -extern int sysctl_hung_task_warnings; -int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos); #else /* Avoid need for ifdefs elsewhere in the code */ enum { sysctl_hung_task_timeout_secs = 0 }; diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 9888e2bc8c767..52501e5f76554 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -63,7 +63,9 @@ static struct task_struct *watchdog_task; * Should we dump all CPUs backtraces in a hung task event? * Defaults to 0, can be changed via sysctl. */ -unsigned int __read_mostly sysctl_hung_task_all_cpu_backtrace; +static unsigned int __read_mostly sysctl_hung_task_all_cpu_backtrace; +#else +#define sysctl_hung_task_all_cpu_backtrace 0 #endif /* CONFIG_SMP */
/* @@ -222,11 +224,13 @@ static long hung_timeout_jiffies(unsigned long last_checked, MAX_SCHEDULE_TIMEOUT; }
+#ifdef CONFIG_SYSCTL /* * Process updating of timeout sysctl */ -int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos) +static int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, + void __user *buffer, + size_t *lenp, loff_t *ppos) { int ret;
@@ -241,6 +245,76 @@ int proc_dohung_task_timeout_secs(struct ctl_table *table, int write, return ret; }
+/* + * This is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs + * and hung_task_check_interval_secs + */ +static const unsigned long hung_task_timeout_max = (LONG_MAX / HZ); +static struct ctl_table hung_task_sysctls[] = { +#ifdef CONFIG_SMP + { + .procname = "hung_task_all_cpu_backtrace", + .data = &sysctl_hung_task_all_cpu_backtrace, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, +#endif /* CONFIG_SMP */ + { + .procname = "hung_task_panic", + .data = &sysctl_hung_task_panic, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { + .procname = "hung_task_check_count", + .data = &sysctl_hung_task_check_count, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + }, + { + .procname = "hung_task_timeout_secs", + .data = &sysctl_hung_task_timeout_secs, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_dohung_task_timeout_secs, + .extra2 = (void *)&hung_task_timeout_max, + }, + { + .procname = "hung_task_check_interval_secs", + .data = &sysctl_hung_task_check_interval_secs, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = proc_dohung_task_timeout_secs, + .extra2 = (void *)&hung_task_timeout_max, + }, + { + .procname = "hung_task_warnings", + .data = &sysctl_hung_task_warnings, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_NEG_ONE, + }, + {} +}; + +static void __init hung_task_sysctl_init(void) +{ + register_sysctl_init("kernel", hung_task_sysctls); +} +#else +#define hung_task_sysctl_init() do { } while (0) +#endif /* CONFIG_SYSCTL */ + + static atomic_t reset_hung_task = ATOMIC_INIT(0);
void reset_hung_task_detector(void) @@ -310,6 +384,7 @@ static int __init hung_task_init(void) pm_notifier(hungtask_pm_notify, 0);
watchdog_task = kthread_run(watchdog, NULL, "khungtaskd"); + hung_task_sysctl_init();
return 0; } diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 4554e80c42729..0a84cb7a8bffe 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -133,13 +133,6 @@ static int minolduid; static int ngroups_max = NGROUPS_MAX; static const int cap_last_cap = CAP_LAST_CAP;
-/* - * This is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs - * and hung_task_check_interval_secs - */ -#ifdef CONFIG_DETECT_HUNG_TASK -static unsigned long hung_task_timeout_max = (LONG_MAX/HZ); -#endif
#ifdef CONFIG_INOTIFY_USER #include <linux/inotify.h> @@ -2510,60 +2503,6 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, #endif -#ifdef CONFIG_DETECT_HUNG_TASK -#ifdef CONFIG_SMP - { - .procname = "hung_task_all_cpu_backtrace", - .data = &sysctl_hung_task_all_cpu_backtrace, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, - }, -#endif /* CONFIG_SMP */ - { - .procname = "hung_task_panic", - .data = &sysctl_hung_task_panic, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, - }, - { - .procname = "hung_task_check_count", - .data = &sysctl_hung_task_check_count, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - }, - { - .procname = "hung_task_timeout_secs", - .data = &sysctl_hung_task_timeout_secs, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = proc_dohung_task_timeout_secs, - .extra2 = &hung_task_timeout_max, - }, - { - .procname = "hung_task_check_interval_secs", - .data = &sysctl_hung_task_check_interval_secs, - .maxlen = sizeof(unsigned long), - .mode = 0644, - .proc_handler = proc_dohung_task_timeout_secs, - .extra2 = &hung_task_timeout_max, - }, - { - .procname = "hung_task_warnings", - .data = &sysctl_hung_task_warnings, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_NEG_ONE, - }, -#endif #ifdef CONFIG_RT_MUTEXES { .procname = "max_lock_depth",