From f4f9c5bc8add58a9dd97241b05b974491afb8657 Mon Sep 17 00:00:00 2001
From: jhb <jhb@FreeBSD.org>
Date: Mon, 12 Sep 2016 18:06:42 +0000
Subject: [PATCH] Make device_quiet() an attachment property.

In particular, reset the DF_QUIET flag when detaching from a device so
that a driver that marks a device quiet doesn't dictate policy for a
different driver that may claim the device in the future.

Reviewed by:	rpokala, wblock
MFC after:	2 weeks
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D7803
---
 share/man/man9/device_quiet.9 | 14 ++++++++------
 sys/kern/subr_bus.c           |  7 +++++++
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/share/man/man9/device_quiet.9 b/share/man/man9/device_quiet.9
index 0e5526d689aa..08d88caf4348 100644
--- a/share/man/man9/device_quiet.9
+++ b/share/man/man9/device_quiet.9
@@ -28,7 +28,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd June 21, 1999
+.Dd September 12, 2016
 .Dt DEVICE_QUIET 9
 .Os
 .Sh NAME
@@ -49,16 +49,18 @@
 Each device has a quiet flag associated with it.
 A device is
 verbose by default when it is created but may be quieted to prevent
-the device identification string to be printed during probe.
+printing of the device identification string during attach
+and printing of a message during detach.
 To quiet a device, call
-.Fn device_quiet ,
-to re-enable to probe message (to make the message appear again, for
-example after a
-.Xr device_detach 9 )
+.Fn device_quiet
+during a device driver probe routine.
+To re-enable probe messages,
 call
 .Fn device_verbose .
 To test to see if a device is quieted, call
 .Fn device_is_quiet .
+.Pp
+Devices are implicitly marked verbose after a driver detaches.
 .Sh SEE ALSO
 .Xr device 9
 .Sh AUTHORS
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index ddc5384a82dd..1e188d3cb681 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -2145,6 +2145,12 @@ device_probe_child(device_t dev, device_t child)
 				break;
 			}
 
+			/*
+			 * Reset DF_QUIET in case this driver doesn't
+			 * end up as the best driver.
+			 */
+			device_verbose(child);
+
 			/*
 			 * Probes that return BUS_PROBE_NOWILDCARD or lower
 			 * only match on devices whose driver was explicitly
@@ -2970,6 +2976,7 @@ device_detach(device_t dev)
 	if (!(dev->flags & DF_FIXEDCLASS))
 		devclass_delete_device(dev->devclass, dev);
 
+	device_verbose(dev);
 	dev->state = DS_NOTPRESENT;
 	(void)device_set_driver(dev, NULL);
 	device_sysctl_fini(dev);