+ arm64-enable-perf-events-based-hard-lockup-detector-fix.patch added to mm-nonmm-unstable branch

+ arm64-enable-perf-events-based-hard-lockup-detector-fix.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: arm64: only HAVE_HARDLOCKUP_DETECTOR_PERF if the PMU config is enabled
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     arm64-enable-perf-events-based-hard-lockup-detector-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arm64-enable-perf-events-based-hard-lockup-detector-fix.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Douglas Anderson <dianders@chromium.org>
Subject: arm64: only HAVE_HARDLOCKUP_DETECTOR_PERF if the PMU config is enabled
Date: Tue, 23 May 2023 07:39:53 -0700

If you try to enable the arm64 perf-based hardlockup detector but you
don't enable CONFIG_ARM_PMU then you'll get an error:

arch/arm64/kernel/watchdog_hld.c: In function 'arch_perf_nmi_is_available':
arch/arm64/kernel/watchdog_hld.c:35:16: error: implicit declaration of function 'arm_pmu_irq_is_nmi' [-Werror=implicit-function-declaration]
   35 |         return arm_pmu_irq_is_nmi();

It doesn't make sense to enable HAVE_HARDLOCKUP_DETECTOR_PERF if the
PMU isn't enabled. Let's add a dependency. HW_PERF_EVENTS is a synonum
for ARM_PMU and makes the most logical sense here, so add the
dependency on that.

Link: https://lkml.kernel.org/r/20230523073952.1.I60217a63acc35621e13f10be16c0cd7c363caf8c@changeid
Fixes: 02ea35ee19d9 ("arm64: enable perf events based hard lockup detector")
Closes: https://lore.kernel.org/r/20230522114922.1052421-1-arnd@kernel.org
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm64/Kconfig |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/arm64/Kconfig~arm64-enable-perf-events-based-hard-lockup-detector-fix
+++ a/arch/arm64/Kconfig
@@ -203,7 +203,8 @@ config ARM64
 	select HAVE_FUNCTION_ERROR_INJECTION
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_GCC_PLUGINS
-	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
+	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
+		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
 	select HAVE_HW_BREAKPOINT if PERF_EVENTS
 	select HAVE_IOREMAP_PROT
 	select HAVE_IRQ_TIME_ACCOUNTING
_

Patches currently in -mm which might be from dianders@chromium.org are

migrate_pages-avoid-blocking-for-io-in-migrate_sync_light.patch
watchdog-perf-define-dummy-watchdog_update_hrtimer_threshold-on-correct-config.patch
watchdog-perf-more-properly-prevent-false-positives-with-turbo-modes.patch
watchdog-hardlockup-add-comments-to-touch_nmi_watchdog.patch
watchdog-perf-rename-watchdog_hldc-to-watchdog_perfc.patch
watchdog-hardlockup-move-perf-hardlockup-checking-panic-to-common-watchdogc.patch
watchdog-hardlockup-style-changes-to-watchdog_hardlockup_check-is_hardlockup.patch
watchdog-hardlockup-add-a-cpu-param-to-watchdog_hardlockup_check.patch
watchdog-hardlockup-move-perf-hardlockup-watchdog-petting-to-watchdogc.patch
watchdog-hardlockup-rename-some-nmi-watchdog-constants-function.patch
watchdog-hardlockup-have-the-perf-hardlockup-use-__weak-functions-more-cleanly.patch
watchdog-hardlockup-detect-hard-lockups-using-secondary-buddy-cpus.patch
watchdog-perf-add-a-weak-function-for-an-arch-to-detect-if-perf-can-use-nmis.patch
arm64-enable-perf-events-based-hard-lockup-detector.patch
arm64-enable-perf-events-based-hard-lockup-detector-fix.patch