Commit ab531878 authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core debug changes from Ingo Molnar:
 "This contains mostly kernel debugging related updates:

   - make hung_task detection more configurable to distros
   - add final bits for x86 UV NMI debugging, with related KGDB changes
   - update the mailing-list of MAINTAINERS entries I'm involved with"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hung_task: Display every hung task warning
  sysctl: Add neg_one as a standard constraint
  x86/uv/nmi, kgdb/kdb: Fix UV NMI handler when KDB not configured
  x86/uv/nmi: Fix Sparse warnings
  kgdb/kdb: Fix no KDB config problem
  MAINTAINERS: Restore "L: linux-kernel@vger.kernel.org" entries
parents 14164b46 270750db
......@@ -33,6 +33,10 @@ show up in /proc/sys/kernel:
- domainname
- hostname
- hotplug
- hung_task_panic
- hung_task_check_count
- hung_task_timeout_secs
- hung_task_warnings
- kexec_load_disabled
- kptr_restrict
- kstack_depth_to_print [ X86 only ]
......@@ -288,6 +292,44 @@ Default value is "/sbin/hotplug".
==============================================================
hung_task_panic:
Controls the kernel's behavior when a hung task is detected.
This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
0: continue operation. This is the default behavior.
1: panic immediately.
==============================================================
hung_task_check_count:
The upper bound on the number of tasks that are checked.
This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
==============================================================
hung_task_timeout_secs:
Check interval. When a task in D state did not get scheduled
for more than this value report a warning.
This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
0: means infinite timeout - no checking done.
==============================================================
hung_task_warning:
The maximum number of warnings to report. During a check interval
When this value is reached, no more the warnings will be reported.
This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
-1: report an infinite number of warnings.
==============================================================
kexec_load_disabled:
A toggle indicating if the kexec_load syscall has been disabled. This
......
......@@ -2222,6 +2222,7 @@ F: include/linux/clk.h
CLOCKSOURCE, CLOCKEVENT DRIVERS
M: Daniel Lezcano <daniel.lezcano@linaro.org>
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
S: Supported
F: drivers/clocksource
......@@ -4023,6 +4024,7 @@ F: include/uapi/linux/hid*
HIGH-RESOLUTION TIMERS, CLOCKEVENTS, DYNTICKS
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
S: Maintained
F: Documentation/timers/
......@@ -4694,6 +4696,7 @@ F: net/irda/
IRQ SUBSYSTEM
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core
F: kernel/irq/
......@@ -5325,6 +5328,7 @@ F: drivers/media/usb/dvb-usb-v2/lmedm04*
LOCKDEP AND LOCKSTAT
M: Peter Zijlstra <peterz@infradead.org>
M: Ingo Molnar <mingo@redhat.com>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core/locking
S: Maintained
F: Documentation/lockdep*.txt
......@@ -6622,6 +6626,7 @@ M: Peter Zijlstra <a.p.zijlstra@chello.nl>
M: Paul Mackerras <paulus@samba.org>
M: Ingo Molnar <mingo@redhat.com>
M: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core
S: Supported
F: kernel/events/*
......@@ -6745,6 +6750,7 @@ F: drivers/scsi/pm8001/
POSIX CLOCKS and TIMERS
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
S: Supported
F: fs/timerfd.c
......@@ -7153,6 +7159,7 @@ F: drivers/net/wireless/ray*
RCUTORTURE MODULE
M: Josh Triplett <josh@freedesktop.org>
M: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
L: linux-kernel@vger.kernel.org
S: Supported
T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
F: Documentation/RCU/torture.txt
......@@ -7160,6 +7167,7 @@ F: kernel/rcu/torture.c
RCUTORTURE TEST FRAMEWORK
M: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
L: linux-kernel@vger.kernel.org
S: Supported
T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
F: tools/testing/selftests/rcutorture
......@@ -7183,6 +7191,7 @@ F: net/rds/
READ-COPY UPDATE (RCU)
M: Dipankar Sarma <dipankar@in.ibm.com>
M: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
L: linux-kernel@vger.kernel.org
W: http://www.rdrop.com/users/paulmck/RCU/
S: Supported
T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
......@@ -7492,6 +7501,7 @@ F: drivers/mmc/host/dw_mmc*
TIMEKEEPING, CLOCKSOURCE CORE, NTP
M: John Stultz <john.stultz@linaro.org>
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
S: Supported
F: include/linux/clocksource.h
......@@ -7517,6 +7527,7 @@ F: drivers/watchdog/sc1200wdt.c
SCHEDULER
M: Ingo Molnar <mingo@redhat.com>
M: Peter Zijlstra <peterz@infradead.org>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core
S: Maintained
F: kernel/sched/
......@@ -7884,6 +7895,7 @@ F: mm/sl?b.c
SLEEPABLE READ-COPY UPDATE (SRCU)
M: Lai Jiangshan <laijs@cn.fujitsu.com>
M: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
L: linux-kernel@vger.kernel.org
W: http://www.rdrop.com/users/paulmck/RCU/
S: Supported
T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
......@@ -9587,6 +9599,7 @@ M: Thomas Gleixner <tglx@linutronix.de>
M: Ingo Molnar <mingo@redhat.com>
M: "H. Peter Anvin" <hpa@zytor.com>
M: x86@kernel.org
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/core
S: Maintained
F: Documentation/x86/
......
......@@ -12,7 +12,6 @@ extern enum uv_system_type get_uv_system_type(void);
extern int is_uv_system(void);
extern void uv_cpu_init(void);
extern void uv_nmi_init(void);
extern void uv_register_nmi_notifier(void);
extern void uv_system_init(void);
extern const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
struct mm_struct *mm,
......@@ -26,7 +25,6 @@ static inline enum uv_system_type get_uv_system_type(void) { return UV_NONE; }
static inline int is_uv_system(void) { return 0; }
static inline void uv_cpu_init(void) { }
static inline void uv_system_init(void) { }
static inline void uv_register_nmi_notifier(void) { }
static inline const struct cpumask *
uv_flush_tlb_others(const struct cpumask *cpumask, struct mm_struct *mm,
unsigned long start, unsigned long end, unsigned int cpu)
......
......@@ -980,7 +980,6 @@ void __init uv_system_init(void)
uv_nmi_setup();
uv_cpu_init();
uv_scir_register_cpu_notifier();
uv_register_nmi_notifier();
proc_mkdir("sgi_uv", NULL);
/* register Legacy VGA I/O redirection handler */
......
......@@ -74,7 +74,6 @@ static atomic_t uv_in_nmi;
static atomic_t uv_nmi_cpu = ATOMIC_INIT(-1);
static atomic_t uv_nmi_cpus_in_nmi = ATOMIC_INIT(-1);
static atomic_t uv_nmi_slave_continue;
static atomic_t uv_nmi_kexec_failed;
static cpumask_var_t uv_nmi_cpu_mask;
/* Values for uv_nmi_slave_continue */
......@@ -149,7 +148,8 @@ module_param_named(retry_count, uv_nmi_retry_count, int, 0644);
* "dump" - dump process stack for each cpu
* "ips" - dump IP info for each cpu
* "kdump" - do crash dump
* "kdb" - enter KDB/KGDB (default)
* "kdb" - enter KDB (default)
* "kgdb" - enter KGDB
*/
static char uv_nmi_action[8] = "kdb";
module_param_string(action, uv_nmi_action, sizeof(uv_nmi_action), 0644);
......@@ -504,6 +504,7 @@ static void uv_nmi_touch_watchdogs(void)
}
#if defined(CONFIG_KEXEC)
static atomic_t uv_nmi_kexec_failed;
static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
/* Call crash to dump system state */
......@@ -537,18 +538,45 @@ static inline void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
}
#endif /* !CONFIG_KEXEC */
#ifdef CONFIG_KGDB
#ifdef CONFIG_KGDB_KDB
/* Call KDB from NMI handler */
static void uv_call_kdb(int cpu, struct pt_regs *regs, int master)
static inline int uv_nmi_kdb_reason(void)
{
int ret;
return KDB_REASON_SYSTEM_NMI;
}
#else /* !CONFIG_KGDB_KDB */
static inline int uv_nmi_kdb_reason(void)
{
/* Insure user is expecting to attach gdb remote */
if (uv_nmi_action_is("kgdb"))
return 0;
pr_err("UV: NMI error: KDB is not enabled in this kernel\n");
return -1;
}
#endif /* CONFIG_KGDB_KDB */
/*
* Call KGDB/KDB from NMI handler
*
* Note that if both KGDB and KDB are configured, then the action of 'kgdb' or
* 'kdb' has no affect on which is used. See the KGDB documention for further
* information.
*/
static void uv_call_kgdb_kdb(int cpu, struct pt_regs *regs, int master)
{
if (master) {
int reason = uv_nmi_kdb_reason();
int ret;
if (reason < 0)
return;
/* call KGDB NMI handler as MASTER */
ret = kgdb_nmicallin(cpu, X86_TRAP_NMI, regs,
&uv_nmi_slave_continue);
ret = kgdb_nmicallin(cpu, X86_TRAP_NMI, regs, reason,
&uv_nmi_slave_continue);
if (ret) {
pr_alert("KDB returned error, is kgdboc set?\n");
pr_alert("KGDB returned error, is kgdboc set?\n");
atomic_set(&uv_nmi_slave_continue, SLAVE_EXIT);
}
} else {
......@@ -567,12 +595,12 @@ static void uv_call_kdb(int cpu, struct pt_regs *regs, int master)
uv_nmi_sync_exit(master);
}
#else /* !CONFIG_KGDB_KDB */
static inline void uv_call_kdb(int cpu, struct pt_regs *regs, int master)
#else /* !CONFIG_KGDB */
static inline void uv_call_kgdb_kdb(int cpu, struct pt_regs *regs, int master)
{
pr_err("UV: NMI error: KGDB/KDB is not enabled in this kernel\n");
pr_err("UV: NMI error: KGDB is not enabled in this kernel\n");
}
#endif /* !CONFIG_KGDB_KDB */
#endif /* !CONFIG_KGDB */
/*
* UV NMI handler
......@@ -606,9 +634,9 @@ int uv_handle_nmi(unsigned int reason, struct pt_regs *regs)
if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump"))
uv_nmi_dump_state(cpu, regs, master);
/* Call KDB if enabled */
else if (uv_nmi_action_is("kdb"))
uv_call_kdb(cpu, regs, master);
/* Call KGDB/KDB if enabled */
else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb"))
uv_call_kgdb_kdb(cpu, regs, master);
/* Clear per_cpu "in nmi" flag */
atomic_set(&uv_cpu_nmi.state, UV_NMI_STATE_OUT);
......@@ -634,7 +662,7 @@ int uv_handle_nmi(unsigned int reason, struct pt_regs *regs)
/*
* NMI handler for pulling in CPUs when perf events are grabbing our NMI
*/
int uv_handle_nmi_ping(unsigned int reason, struct pt_regs *regs)
static int uv_handle_nmi_ping(unsigned int reason, struct pt_regs *regs)
{
int ret;
......@@ -651,7 +679,7 @@ int uv_handle_nmi_ping(unsigned int reason, struct pt_regs *regs)
return ret;
}
void uv_register_nmi_notifier(void)
static void uv_register_nmi_notifier(void)
{
if (register_nmi_handler(NMI_UNKNOWN, uv_handle_nmi, 0, "uv"))
pr_warn("UV: NMI handler failed to register\n");
......@@ -695,6 +723,5 @@ void uv_nmi_setup(void)
uv_hub_nmi_per(cpu) = uv_hub_nmi_list[nid];
}
BUG_ON(!alloc_cpumask_var(&uv_nmi_cpu_mask, GFP_KERNEL));
uv_register_nmi_notifier();
}
......@@ -310,7 +310,8 @@ extern int
kgdb_handle_exception(int ex_vector, int signo, int err_code,
struct pt_regs *regs);
extern int kgdb_nmicallback(int cpu, void *regs);
extern int kgdb_nmicallin(int cpu, int trapnr, void *regs, atomic_t *snd_rdy);
extern int kgdb_nmicallin(int cpu, int trapnr, void *regs, int err_code,
atomic_t *snd_rdy);
extern void gdbstub_exit(int status);
extern int kgdb_single_step;
......
......@@ -5,7 +5,7 @@
extern int sysctl_hung_task_check_count;
extern unsigned int sysctl_hung_task_panic;
extern unsigned long sysctl_hung_task_timeout_secs;
extern unsigned long sysctl_hung_task_warnings;
extern int sysctl_hung_task_warnings;
extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos);
......
......@@ -736,7 +736,8 @@ int kgdb_nmicallback(int cpu, void *regs)
return 1;
}
int kgdb_nmicallin(int cpu, int trapnr, void *regs, atomic_t *send_ready)
int kgdb_nmicallin(int cpu, int trapnr, void *regs, int err_code,
atomic_t *send_ready)
{
#ifdef CONFIG_SMP
if (!kgdb_io_ready(0) || !send_ready)
......@@ -750,7 +751,7 @@ int kgdb_nmicallin(int cpu, int trapnr, void *regs, atomic_t *send_ready)
ks->cpu = cpu;
ks->ex_vector = trapnr;
ks->signo = SIGTRAP;
ks->err_code = KGDB_KDB_REASON_SYSTEM_NMI;
ks->err_code = err_code;
ks->linux_regs = regs;
ks->send_ready = send_ready;
kgdb_cpu_enter(ks, regs, DCPU_WANT_MASTER);
......
......@@ -75,13 +75,11 @@ extern int kdb_stub(struct kgdb_state *ks);
extern int kdb_parse(const char *cmdstr);
extern int kdb_common_init_state(struct kgdb_state *ks);
extern int kdb_common_deinit_state(void);
#define KGDB_KDB_REASON_SYSTEM_NMI KDB_REASON_SYSTEM_NMI
#else /* ! CONFIG_KGDB_KDB */
static inline int kdb_stub(struct kgdb_state *ks)
{
return DBG_PASS_EVENT;
}
#define KGDB_KDB_REASON_SYSTEM_NMI 0
#endif /* CONFIG_KGDB_KDB */
#endif /* _DEBUG_CORE_H_ */
......@@ -37,7 +37,7 @@ int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;
*/
unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT;
unsigned long __read_mostly sysctl_hung_task_warnings = 10;
int __read_mostly sysctl_hung_task_warnings = 10;
static int __read_mostly did_panic;
......@@ -98,7 +98,9 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
if (!sysctl_hung_task_warnings)
return;
sysctl_hung_task_warnings--;
if (sysctl_hung_task_warnings > 0)
sysctl_hung_task_warnings--;
/*
* Ok, the task did not get scheduled for more than 2 minutes,
......
......@@ -121,6 +121,8 @@ extern int blk_iopoll_enabled;
static int sixty = 60;
#endif
static int __maybe_unused neg_one = -1;
static int zero;
static int __maybe_unused one = 1;
static int __maybe_unused two = 2;
......@@ -997,9 +999,10 @@ static struct ctl_table kern_table[] = {
{
.procname = "hung_task_warnings",
.data = &sysctl_hung_task_warnings,
.maxlen = sizeof(unsigned long),
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_doulongvec_minmax,
.proc_handler = proc_dointvec_minmax,
.extra1 = &neg_one,
},
#endif
#ifdef CONFIG_COMPAT
......
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