From 546d925cb44f1da7efee76bfebb42df8fdbc83a8 Mon Sep 17 00:00:00 2001 From: ShengYi Hung Date: Sat, 3 Jan 2026 14:12:26 +0800 Subject: [PATCH] ichwd: Add manual for i6300esb watchdog Reviewed by: ziaee, mhorne Approved by: lwhsu (mentor) MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D54466 --- share/man/man4/ichwd.4 | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/share/man/man4/ichwd.4 b/share/man/man4/ichwd.4 index cc6924f7f86..25de73778d3 100644 --- a/share/man/man4/ichwd.4 +++ b/share/man/man4/ichwd.4 @@ -23,7 +23,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd August 20, 2008 +.Dd January 3, 2026 .Dt ICHWD 4 .Os .Sh NAME @@ -55,6 +55,16 @@ The ICH WDT counts down in ticks of approximately 0.6 seconds; the exact value depends on hardware quality and environmental factors. Supported watchdog intervals range from 2 to 63 ticks. .Pp +In QEMU, there is a dedicated watchdog implementation for x86 +systems based on the Intel 6300ESB controller hub. +Support for this watchdog is provided by this kernel module. +.Pp +Optionally, set the +.Va hw.i6300esbwd.x.locked=1 +.Xr sysctl 8 +to prevent users from disabling the watchdog timeout check +after it has been enabled. +.Pp Note that on some ICH-based systems, the WDT may be present but disabled, either in hardware or by the BIOS. The