[PATCH v3.7+] HID: magicmouse: fix race between input_register() and probe()
flat view
STALE4938d
From: Benjamin Tissoires <hidden>
Date: 2013-04-02 09:13:02
Also in:
lkml
Subsystem:
hid core layer, the rest · Maintainers:
Jiri Kosina, Benjamin Tissoires, Linus Torvalds
Since kernel 3.7, it appears that the input registration occured before the end of magicmouse_setup_input(). This is shown by receiving a lot of "EV_SYN SYN_REPORT 1" instead of normal "EV_SYN SYN_REPORT 0". This value means that the output buffer is full, and the user space is loosing events. Using .input_configured guarantees that the race is not occuring, and that the call of "input_set_events_per_packet(input, 60)" is taken into account by input_register(). Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=908604 Reported-and-Tested-By: Clarke Wixon <redacted> Signed-off-by: Benjamin Tissoires <redacted> --- Hi Jiri, this one can goes to stable (so 3.8) as well. Cheers, Benjamin drivers/hid/hid-magicmouse.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-)
diff --git a/drivers/hid/hid-magicmouse.c b/drivers/hid/hid-magicmouse.c
index ef89573..5bc3734 100644
--- a/drivers/hid/hid-magicmouse.c
+++ b/drivers/hid/hid-magicmouse.c@@ -461,6 +461,21 @@ static int magicmouse_input_mapping(struct hid_device *hdev, return 0; } +static void magicmouse_input_configured(struct hid_device *hdev, + struct hid_input *hi) + +{ + struct magicmouse_sc *msc = hid_get_drvdata(hdev); + + int ret = magicmouse_setup_input(msc->input, hdev); + if (ret) { + hid_err(hdev, "magicmouse setup input failed (%d)\n", ret); + /* clean msc->input to notify probe() of the failure */ + msc->input = NULL; + } +} + + static int magicmouse_probe(struct hid_device *hdev, const struct hid_device_id *id) {
@@ -492,15 +507,10 @@ static int magicmouse_probe(struct hid_device *hdev, goto err_free; } - /* We do this after hid-input is done parsing reports so that - * hid-input uses the most natural button and axis IDs. - */ - if (msc->input) { - ret = magicmouse_setup_input(msc->input, hdev); - if (ret) { - hid_err(hdev, "magicmouse setup input failed (%d)\n", ret); - goto err_stop_hw; - } + if (!msc->input) { + hid_err(hdev, "magicmouse input not registered\n"); + ret = -ENOMEM; + goto err_stop_hw; } if (id->product == USB_DEVICE_ID_APPLE_MAGICMOUSE)
@@ -567,6 +577,7 @@ static struct hid_driver magicmouse_driver = { .remove = magicmouse_remove, .raw_event = magicmouse_raw_event, .input_mapping = magicmouse_input_mapping, + .input_configured = magicmouse_input_configured, }; module_hid_driver(magicmouse_driver);
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1.8.1.4