diff options
| author | Douglas Anderson <dianders@chromium.org> | 2023-05-26 18:41:32 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-06-19 16:25:26 -0700 |
| commit | 6426e8d1f27417834ea37e75a9ead832d1cf7713 (patch) | |
| tree | 161ef5a0f42851227d844f04d884485a6b58427d | |
| parent | 9ec272c586b07d1abf73438524bd12b1df9c5f9b (diff) | |
watchdog/hardlockup: HAVE_NMI_WATCHDOG must implement watchdog_hardlockup_probe()
Right now there is one arch (sparc64) that selects HAVE_NMI_WATCHDOG
without selecting HAVE_HARDLOCKUP_DETECTOR_ARCH. Because of that one
architecture, we have some special case code in the watchdog core to
handle the fact that watchdog_hardlockup_probe() isn't implemented.
Let's implement watchdog_hardlockup_probe() for sparc64 and get rid of the
special case.
As a side effect of doing this, code inspection tells us that we could fix
a minor bug where the system won't properly realize that NMI watchdogs are
disabled. Specifically, on powerpc if CONFIG_PPC_WATCHDOG is turned off
the arch might still select CONFIG_HAVE_HARDLOCKUP_DETECTOR_ARCH which
selects CONFIG_HAVE_NMI_WATCHDOG. Since CONFIG_PPC_WATCHDOG was off then
nothing will override the "weak" watchdog_hardlockup_probe() and we'll
fallback to looking at CONFIG_HAVE_NMI_WATCHDOG.
Link: https://lkml.kernel.org/r/20230526184139.2.Ic6ebbf307ca0efe91f08ce2c1eb4a037ba6b0700@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Suggested-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | arch/Kconfig | 3 | ||||
| -rw-r--r-- | arch/sparc/kernel/nmi.c | 5 | ||||
| -rw-r--r-- | kernel/watchdog.c | 13 |
3 files changed, 7 insertions, 14 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 205fd23e0cad..422f0ffa269e 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -405,7 +405,8 @@ config HAVE_NMI_WATCHDOG bool help The arch provides a low level NMI watchdog. It provides - asm/nmi.h, and defines its own arch_touch_nmi_watchdog(). + asm/nmi.h, and defines its own watchdog_hardlockup_probe() and + arch_touch_nmi_watchdog(). config HAVE_HARDLOCKUP_DETECTOR_ARCH bool diff --git a/arch/sparc/kernel/nmi.c b/arch/sparc/kernel/nmi.c index 9d9e29b75c43..17cdfdbf1f3b 100644 --- a/arch/sparc/kernel/nmi.c +++ b/arch/sparc/kernel/nmi.c @@ -65,6 +65,11 @@ void arch_touch_nmi_watchdog(void) } EXPORT_SYMBOL(arch_touch_nmi_watchdog); +int __init watchdog_hardlockup_probe(void) +{ + return 0; +} + static void die_nmi(const char *str, struct pt_regs *regs, int do_panic) { int this_cpu = smp_processor_id(); diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 4b9e31edb47f..62230f5b8878 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -217,19 +217,6 @@ void __weak watchdog_hardlockup_disable(unsigned int cpu) { } */ int __weak __init watchdog_hardlockup_probe(void) { - /* - * If CONFIG_HAVE_NMI_WATCHDOG is defined then an architecture - * is assumed to have the hard watchdog available and we return 0. - */ - if (IS_ENABLED(CONFIG_HAVE_NMI_WATCHDOG)) - return 0; - - /* - * Hardlockup detectors other than those using CONFIG_HAVE_NMI_WATCHDOG - * are required to implement a non-weak version of this probe function - * to tell whether they are available. If they don't override then - * we'll return -ENODEV. - */ return -ENODEV; } |