Commit-ID: 51d4052b01ca555e0d1d5fe297b309beb6c64aa0
Gitweb: http://git.kernel.org/tip/51d4052b01ca555e0d1d5fe297b309beb6c64aa0
Author: Thomas Gleixner <[email protected]>
AuthorDate: Tue, 12 Sep 2017 21:37:14 +0200
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 14 Sep 2017 11:41:07 +0200
watchdog/sysctl: Get rid of the #ifdeffery
The sysctl of the nmi_watchdog file prevents writes by setting:
min = max = 0
if none of the users is enabled. That involves ifdeffery and is competely
non obvious.
If none of the facilities is enabeld, then the file can simply be made read
only. Move the ifdeffery into the header and use a constant for file
permissions.
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Don Zickus <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Sebastian Siewior <[email protected]>
Cc: Ulrich Obergfell <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
include/linux/nmi.h | 6 ++++++
kernel/sysctl.c | 6 +-----
2 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index cfebb3b..5774b443 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -81,6 +81,12 @@ extern unsigned int hardlockup_panic;
static inline void hardlockup_detector_disable(void) {}
#endif
+#if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
+# define NMI_WATCHDOG_SYSCTL_PERM 0644
+#else
+# define NMI_WATCHDOG_SYSCTL_PERM 0444
+#endif
+
#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
extern void arch_touch_nmi_watchdog(void);
extern void hardlockup_detector_perf_stop(void);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 6648fbb..539cb4e 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -891,14 +891,10 @@ static struct ctl_table kern_table[] = {
.procname = "nmi_watchdog",
.data = &nmi_watchdog_enabled,
.maxlen = sizeof (int),
- .mode = 0644,
+ .mode = NMI_WATCHDOG_SYSCTL_PERM,
.proc_handler = proc_nmi_watchdog,
.extra1 = &zero,
-#if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
.extra2 = &one,
-#else
- .extra2 = &zero,
-#endif
},
{
.procname = "watchdog_cpumask",
