linux-kernel - [ 49/56] watchdog: using u64 in get_sample

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

Date:	Fri, 30 Nov 2012 10:55:41 -0800
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	alan@...rguk.ukuu.org.uk,
	liu chuansheng <chuansheng.liu@...el.com>,
	Don Zickus <dzickus@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Shuah Khan <shuah.khan@...com>
Subject: [ 49/56] watchdog: using u64 in get_sample_period()

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Chuansheng Liu <chuansheng.liu@...el.com>

commit 8ffeb9b0e6369135bf03a073514f571ef10606b9 upstream.

In get_sample_period(), unsigned long is not enough:

  watchdog_thresh * 2 * (NSEC_PER_SEC / 5)

case1:
  watchdog_thresh is 10 by default, the sample value will be: 0xEE6B2800

case2:
 set watchdog_thresh is 20, the sample value will be: 0x1 DCD6 5000

In case2, we need use u64 to express the sample period.  Otherwise,
changing the threshold thru proc often can not be successful.

Signed-off-by: liu chuansheng <chuansheng.liu@...el.com>
Acked-by: Don Zickus <dzickus@...hat.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Shuah Khan <shuah.khan@...com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 kernel/watchdog.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -112,7 +112,7 @@ static unsigned long get_timestamp(int t
 	return cpu_clock(this_cpu) >> 30LL;  /* 2^30 ~= 10^9 */
 }
 
-static unsigned long get_sample_period(void)
+static u64 get_sample_period(void)
 {
 	/*
 	 * convert watchdog_thresh from seconds to ns
@@ -121,7 +121,7 @@ static unsigned long get_sample_period(v
 	 * and hard thresholds) to increment before the
 	 * hardlockup detector generates a warning
 	 */
-	return get_softlockup_thresh() * (NSEC_PER_SEC / 5);
+	return get_softlockup_thresh() * ((u64)NSEC_PER_SEC / 5);
 }
 
 /* Commands for resetting the watchdog */


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/