| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20230301234753.28582-18-ricardo.neri-calderon@linux.intel.com>
Date: Wed, 1 Mar 2023 15:47:46 -0800
From: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
To: Tony Luck <tony.luck@...el.com>,
Dave Hansen <dave.hansen@...el.com>,
"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
Reinette Chatre <reinette.chatre@...el.com>,
Dan Williams <dan.j.williams@...el.com>,
Len Brown <len.brown@...el.com>
Cc: Andi Kleen <ak@...ux.intel.com>,
Stephane Eranian <eranian@...gle.com>,
"Ravi V. Shankar" <ravi.v.shankar@...el.com>,
Ricardo Neri <ricardo.neri@...el.com>,
linuxppc-dev@...ts.ozlabs.org, iommu@...ts.linux-foundation.org,
linux-kernel@...r.kernel.org,
Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>,
Nicholas Piggin <npiggin@...il.com>,
Andrew Morton <akpm@...ux-foundation.org>
Subject: [PATCH v7 17/24] watchdog/hardlockup: Decouple the hardlockup detector from perf
The current default implementation of the hardlockup detector assumes that
it is implemented using perf events. However, the hardlockup detector can
be driven by other sources of non-maskable interrupts (e.g., a properly
configured timer).
Group and wrap in #ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF all the code
specific to perf: create and manage perf events, stop and start the perf-
based detector.
The generic portion of the detector (monitor the timers' thresholds, check
timestamps and detect hardlockups as well as the implementation of
arch_touch_nmi_watchdog()) is now selected with the new intermediate config
symbol CONFIG_HARDLOCKUP_DETECTOR_CORE.
The perf-based implementation of the detector selects the new intermediate
symbol. Other implementations should do the same.
Cc: Andi Kleen <ak@...ux.intel.com>
Cc: Nicholas Piggin <npiggin@...il.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: Stephane Eranian <eranian@...gle.com>
Cc: "Ravi V. Shankar" <ravi.v.shankar@...el.com>
Cc: iommu@...ts.linux-foundation.org
Cc: linuxppc-dev@...ts.ozlabs.org
Reviewed-by: Tony Luck <tony.luck@...el.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
---
Changes since v6:
* None
Changes since v5:
* None
Changes since v4:
* None
Changes since v3:
* Squashed into this patch a previous patch to make
arch_touch_nmi_watchdog() part of the core detector code.
Changes since v2:
* Undid split of the generic hardlockup detector into a separate file.
(Thomas Gleixner)
* Added a new intermediate symbol CONFIG_HARDLOCKUP_DETECTOR_CORE to
select generic parts of the detector (Paul E. McKenney,
Thomas Gleixner).
Changes since v1:
* Make the generic detector code with CONFIG_HARDLOCKUP_DETECTOR.
---
include/linux/nmi.h | 5 ++++-
kernel/Makefile | 2 +-
kernel/watchdog_hld.c | 32 ++++++++++++++++++++------------
lib/Kconfig.debug | 4 ++++
4 files changed, 29 insertions(+), 14 deletions(-)
diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index 75038cb2710e..a38c4509f9eb 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -94,8 +94,11 @@ static inline void hardlockup_detector_disable(void) {}
# define NMI_WATCHDOG_SYSCTL_PERM 0444
#endif
-#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
+#if defined(CONFIG_HARDLOCKUP_DETECTOR_CORE)
extern void arch_touch_nmi_watchdog(void);
+#endif
+
+#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
extern void hardlockup_detector_perf_stop(void);
extern void hardlockup_detector_perf_restart(void);
extern void hardlockup_detector_perf_disable(void);
diff --git a/kernel/Makefile b/kernel/Makefile
index 10ef068f598d..f35fad36cf81 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -91,7 +91,7 @@ obj-$(CONFIG_FAIL_FUNCTION) += fail_function.o
obj-$(CONFIG_KGDB) += debug/
obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o
-obj-$(CONFIG_HARDLOCKUP_DETECTOR_PERF) += watchdog_hld.o
+obj-$(CONFIG_HARDLOCKUP_DETECTOR_CORE) += watchdog_hld.o
obj-$(CONFIG_SECCOMP) += seccomp.o
obj-$(CONFIG_RELAY) += relay.o
obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index b352e507b17f..bb6435978c46 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -22,12 +22,8 @@
static DEFINE_PER_CPU(bool, hard_watchdog_warn);
static DEFINE_PER_CPU(bool, watchdog_nmi_touch);
-static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
-static DEFINE_PER_CPU(struct perf_event *, dead_event);
-static struct cpumask dead_events_mask;
static unsigned long hardlockup_allcpu_dumped;
-static atomic_t watchdog_cpus = ATOMIC_INIT(0);
notrace void arch_touch_nmi_watchdog(void)
{
@@ -98,14 +94,6 @@ static inline bool watchdog_check_timestamp(void)
}
#endif
-static struct perf_event_attr wd_hw_attr = {
- .type = PERF_TYPE_HARDWARE,
- .config = PERF_COUNT_HW_CPU_CYCLES,
- .size = sizeof(struct perf_event_attr),
- .pinned = 1,
- .disabled = 1,
-};
-
void inspect_for_hardlockups(struct pt_regs *regs)
{
if (__this_cpu_read(watchdog_nmi_touch) == true) {
@@ -157,6 +145,24 @@ void inspect_for_hardlockups(struct pt_regs *regs)
return;
}
+#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
+#undef pr_fmt
+#define pr_fmt(fmt) "NMI perf watchdog: " fmt
+
+static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
+static DEFINE_PER_CPU(struct perf_event *, dead_event);
+static struct cpumask dead_events_mask;
+
+static atomic_t watchdog_cpus = ATOMIC_INIT(0);
+
+static struct perf_event_attr wd_hw_attr = {
+ .type = PERF_TYPE_HARDWARE,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ .size = sizeof(struct perf_event_attr),
+ .pinned = 1,
+ .disabled = 1,
+};
+
/* Callback function for perf event subsystem */
static void watchdog_overflow_callback(struct perf_event *event,
struct perf_sample_data *data,
@@ -298,3 +304,5 @@ int __init hardlockup_detector_perf_init(void)
}
return ret;
}
+
+#endif /* CONFIG_HARDLOCKUP_DETECTOR_PERF */
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c8b379e2e9ad..1ff53c5995b1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1025,9 +1025,13 @@ config BOOTPARAM_SOFTLOCKUP_PANIC
Say N if unsure.
+config HARDLOCKUP_DETECTOR_CORE
+ bool
+
config HARDLOCKUP_DETECTOR_PERF
bool
select SOFTLOCKUP_DETECTOR
+ select HARDLOCKUP_DETECTOR_CORE
#
# Enables a timestamp based low pass filter to compensate for perf based
--
2.25.1
Powered by blists - more mailing lists