[patch 10/16] usbusx2y: prevent oops & dead keyboard on usb unplugging

Chris Wright
2005-05-23T23:35:59Z

Summary: prevent oops & dead keyboard on usb unplugging while the device is being used

Without this patch, some usb kobjects, which are parents to
the usx2y's kobjects can be freed before the usx2y's.
This led to an oops in get_kobj_path_length() and a dead
keyboard, when the usx2y's kobjects were freed.
The patch ensures the correct sequence.
Tested ok on kernel 2.6.12-rc2.

Present in ALSA cvs

Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
sound/usb/usx2y/usbusx2y.c | 11 +++++++----
1 files changed, 7 insertions(+), 4 deletions(-)

--- linux-2.6.11.10.orig/sound/usb/usx2y/usbusx2y.c 2005-05-16 10:52:18.000000000 -0700
+++ linux-2.6.11.10/sound/usb/usx2y/usbusx2y.c 2005-05-20 09:36:42.067778552 -0700
@@ -1,6 +1,11 @@
/*
* usbusy2y.c - ALSA USB US-428 Driver
*
+2005-04-14 Karsten Wiese
+ Version 0.8.7.2:
+ Call snd_card_free() instead of snd_card_free_in_thread() to prevent oops with dead keyboard symptom.
+ Tested ok with kernel 2.6.12-rc2.
+
2004-12-14 Karsten Wiese
Version 0.8.7.1:
snd_pcm_open for rawusb pcm-devices now returns -EBUSY if called without rawusb's hwdep device being open.
@@ -143,7 +148,7 @@

MODULE_AUTHOR("Karsten Wiese <annabellesgarden@yahoo.de>");
-MODULE_DESCRIPTION("TASCAM "NAME_ALLCAPS" Version 0.8.7.1");
+MODULE_DESCRIPTION("TASCAM "NAME_ALLCAPS" Version 0.8.7.2");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{TASCAM(0x1604), "NAME_ALLCAPS"(0x8001)(0x8005)(0x8007) }}");

@@ -430,8 +435,6 @@
if (ptr) {
usX2Ydev_t* usX2Y = usX2Y((snd_card_t*)ptr);
struct list_head* p;
- if (usX2Y->chip_status == USX2Y_STAT_CHIP_HUP) // on 2.6.1 kernel snd_usbmidi_disconnect()
- return; // calls us back. better leave :-) .
usX2Y->chip.shutdown = 1;
usX2Y->chip_status = USX2Y_STAT_CHIP_HUP;
usX2Y_unlinkSeq(&usX2Y->AS04);
@@ -443,7 +446,7 @@
}
if (usX2Y->us428ctls_sharedmem)
wake_up(&usX2Y->us428ctls_wait_queue_head);
- snd_card_free_in_thread((snd_card_t*)ptr);
+ snd_card_free((snd_card_t*)ptr);
}
}