Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1ccfd633 authored by Karsten Keil's avatar Karsten Keil Committed by Linus Torvalds
Browse files

i4l: Fix random hard freeze with AVM c4 card 



The patch
- Includes the call to capilib_data_b3_req in the spinlock. This routine
  in turn calls the offending mq_enqueue routine that triggered the
  freeze if not locked.  This should also fix other indicators of
  incosistent capilib_msgidqueue list, that trigger messages like:
  Oct  5 03:05:57 BERL0 kernel: kcapi: msgid 3019 ncci 0x30301 not on queue
  that we saw several times a day (usually several in a row).
- Fixes all occurrences of c4_dispatch_tx to be called with active
  spinlock, there were some instances where no lock was active. Mostly
  these are in very infrequently called routines, so the additional
  performance penalty is minimal.

Signed-off-by: default avatarKarsten Keil <kkeil@suse.de>
Signed-off-by: default avatarRainer Brestan <rainer.brestan@frequentis.com>
Signed-off-by: default avatarRalf Schlatterbeck <rsc@runtux.com>
Cc: <stable@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 9713d9e6

drivers/isdn/hardware/avm/c4.c

+11 −3
Original line number Diff line number Diff line
@@ -727,6 +727,7 @@ static void c4_send_init(avmcard *card) 
{

	struct sk_buff *skb;

	void *p;

	unsigned long flags;



	skb = alloc_skb(15, GFP_ATOMIC);

	if (!skb) {
@@ -744,12 +745,15 @@ static void c4_send_init(avmcard *card) 
	skb_put(skb, (u8 *)p - (u8 *)skb->data);



	skb_queue_tail(&card->dma->send_queue, skb);

	spin_lock_irqsave(&card->lock, flags);

	c4_dispatch_tx(card);

	spin_unlock_irqrestore(&card->lock, flags);

}



static int queue_sendconfigword(avmcard *card, u32 val)

{

	struct sk_buff *skb;

	unsigned long flags;

	void *p;



	skb = alloc_skb(3+4, GFP_ATOMIC);
@@ -766,7 +770,9 @@ static int queue_sendconfigword(avmcard *card, u32 val) 
	skb_put(skb, (u8 *)p - (u8 *)skb->data);



	skb_queue_tail(&card->dma->send_queue, skb);

	spin_lock_irqsave(&card->lock, flags);

	c4_dispatch_tx(card);

	spin_unlock_irqrestore(&card->lock, flags);

	return 0;

}
@@ -986,7 +992,9 @@ static void c4_release_appl(struct capi_ctr *ctrl, u16 appl) 
	struct sk_buff *skb;

	void *p;



	spin_lock_irqsave(&card->lock, flags);

	capilib_release_appl(&cinfo->ncci_head, appl);

	spin_unlock_irqrestore(&card->lock, flags);



	if (ctrl->cnr == card->cardnr) {

		skb = alloc_skb(7, GFP_ATOMIC);
@@ -1019,6 +1027,7 @@ static u16 c4_send_message(struct capi_ctr *ctrl, struct sk_buff *skb) 
	u16 retval = CAPI_NOERROR;

	unsigned long flags;



	spin_lock_irqsave(&card->lock, flags);

	if (CAPIMSG_CMD(skb->data) == CAPI_DATA_B3_REQ) {

		retval = capilib_data_b3_req(&cinfo->ncci_head,

					     CAPIMSG_APPID(skb->data),
@@ -1027,10 +1036,9 @@ static u16 c4_send_message(struct capi_ctr *ctrl, struct sk_buff *skb) 
	}

	if (retval == CAPI_NOERROR) {

		skb_queue_tail(&card->dma->send_queue, skb);

		spin_lock_irqsave(&card->lock, flags);

		c4_dispatch_tx(card);

		spin_unlock_irqrestore(&card->lock, flags);

	}

	spin_unlock_irqrestore(&card->lock, flags);

	return retval;

}