Re: bluetooth related firmware loader spew on resume.

[Takashi Iwai <tiwai@suse.de>]

At Tue, 11 Nov 2014 13:12:28 -0500,
Dave Jones wrote:
> 
> Since the addition of 10d4c6736ea "Bluetooth: btusb: Add Broadcom patch
> RAM support", I (and a number of other people[*]) have been seeing
> this trace on resume from suspend.
> 
> WARNING: CPU: 1 PID: 8565 at drivers/base/firmware_class.c:1127 _request_firmware+0x4c1/0x7c0()
> CPU: 1 PID: 8565 Comm: kworker/u17:0 Not tainted 3.17.2-200.fc20.x86_64 #1
> Hardware name: LENOVO 2356JK8/2356JK8, BIOS G7ET94WW (2.54 ) 04/30/2013
> Workqueue: hci0 hci_power_on [bluetooth]
> 0000000000000000 00000000f52a564b ffff8800a8c63be8 ffffffff817271cc
> 0000000000000000 ffff8800a8c63c20 ffffffff81094ced ffff8800a8c63d10
> ffff8801365ddf00 ffff8801387b4b00 ffff8800a8c63d08 00000000fffffff5
> Call Trace:
> [<ffffffff817271cc>] dump_stack+0x45/0x56
> [<ffffffff81094ced>] warn_slowpath_common+0x7d/0xa0
> [<ffffffff81094e1a>] warn_slowpath_null+0x1a/0x20
> [<ffffffff814965c1>] _request_firmware+0x4c1/0x7c0
> [<ffffffff8137b9b9>] ? snprintf+0x49/0x70
> [<ffffffff814968f1>] request_firmware+0x31/0x50
> [<ffffffffa0943bf3>] btusb_setup_bcm_patchram+0x83/0x550 [btusb]
> [<ffffffff8148ecf6>] ? rpm_idle+0xd6/0x2b0
> [<ffffffffa0649051>] hci_dev_do_open+0xe1/0xa60 [bluetooth]
> ACPI: \_SB_.PCI0.LPC_.EC__.BAT1: docking
> Restarting tasks ... 
> [<ffffffff810bcb3d>] ? ttwu_do_activate.constprop.90+0x5d/0x70
> [<ffffffffa064a1c0>] hci_power_on+0x40/0x1e0 [bluetooth]
> [<ffffffff810f53fb>] ? lock_timer_base.isra.34+0x2b/0x50
> [<ffffffff810acc39>] process_one_work+0x149/0x3d0
> [<ffffffff810ad2bb>] worker_thread+0x11b/0x490
> [<ffffffff810ad1a0>] ? rescuer_thread+0x2e0/0x2e0
> [<ffffffff810b2318>] kthread+0xd8/0xf0
> [<ffffffff810b2240>] ? kthread_create_on_node+0x190/0x190
> [<ffffffff8172e7bc>] ret_from_fork+0x7c/0xb0
> [<ffffffff810b2240>] ? kthread_create_on_node+0x190/0x190
> ---[ end trace 75a0e9c7f33ebb4c ]---
> bluetooth hci0: firmware: brcm/BCM20702A0-0a5c-21e6.hcd will not be loaded
> Bluetooth: hci0: BCM: patch brcm/BCM20702A0-0a5c-21e6.hcd not found
> 
> 
> At first I thought it was just over-reaction to the file being missing, but
> looking at the WARN_ON, it appears that we're trying to invoke the firmware
> loader before userspace is back up ?
> 
> In this (and probably other related) kernel, CONFIG_FW_LOADER_USER_HELPER is unset,
> in case that matters at all.

If it's the case where no matching firmware file is present, the patch
below might help.  It's only compile-tested.


Takashi

-- 8< --
From: Takashi Iwai <tiwai@suse.de>
Subject: [PATCH] btusb: Give up firmware loading once when failed

Otherwise it may trigger request_firmware() for the non-existing file
in the resume path, resulting in a warning.  For the success paths,
calling request_firmware() is fine, as it's cached properly at
suspend.  The problem is only for the error paths.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 drivers/bluetooth/btusb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index edfc17bfcd44..62d8e23fd3cb 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -1569,6 +1569,7 @@ static int btusb_setup_intel(struct hci_dev *hdev)
 	if (!fw) {
 		kfree_skb(skb);
 		btusb_check_bdaddr_intel(hdev);
+		hdev->setup = NULL;
 		return 0;
 	}
 	fw_ptr = fw->data;
@@ -1756,6 +1757,7 @@ static int btusb_setup_bcm_patchram(struct hci_dev *hdev)
 	ret = request_firmware(&fw, fw_name, &hdev->dev);
 	if (ret < 0) {
 		BT_INFO("%s: BCM: patch %s not found", hdev->name, fw_name);
+		hdev->setup = NULL;
 		return 0;
 	}
 
-- 
2.1.3