linux-kernel - [PATCH v15 clocksource] Prohibit clocksource watchdog test when HZ<100

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <20210721212755.GA2066078@paulmck-ThinkPad-P17-Gen-1>
Date:   Wed, 21 Jul 2021 14:27:55 -0700
From:   "Paul E. McKenney" <paulmck@...nel.org>
To:     tglx@...utronix.de
Cc:     linux-kernel@...r.kernel.org, john.stultz@...aro.org,
        sboyd@...nel.org, corbet@....net, Mark.Rutland@....com,
        maz@...nel.org, kernel-team@...com, neeraju@...eaurora.org,
        ak@...ux.intel.com, feng.tang@...el.com, zhengjun.xing@...el.com
Subject: [PATCH v15 clocksource] Prohibit clocksource watchdog test when
 HZ<100

As noted in a comment, use of the TEST_CLOCKSOURCE_WATCHDOG kconfig
option is prohibited when HZ is less than 100 in order to avoid signed
integer overflow.  However, comments can easily be ignored even when they
are actually read.  Therefore, add a "depends" clause to prohibit use
of the TEST_CLOCKSOURCE_WATCHDOG kconfig option when HZ is less than 100.

Reported-by: kernel test robot <lkp@...el.com>
Tested-by: Rong Chen <rong.a.chen@...el.com>
Signed-off-by: Paul E. McKenney <paulmck@...nel.org>
Link: https://lore.kernel.org/lkml/202107040532.wqL30yFp-lkp@intel.com/

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 831212722924c..79487f3dad430 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2612,6 +2612,7 @@ config TEST_FPU
 config TEST_CLOCKSOURCE_WATCHDOG
 	tristate "Test clocksource watchdog in kernel space"
 	depends on CLOCKSOURCE_WATCHDOG
+	depends on HZ >= 100
 	help
 	  Enable this option to create a kernel module that will trigger
 	  a test of the clocksource watchdog.  This module may be loaded