diff options
| author | Karsten Keil <kkeil@suse.de> | 2007-10-18 03:04:31 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-11-16 09:30:23 -0800 |
| commit | 4b3c198a4b5d083eb84abb89fe30e32f562b2771 (patch) | |
| tree | 43f70b917448ad5bdfb02f7b6d176f5bacb9b284 /drivers/isdn | |
| parent | dd0775720aa07a7b1c6a59bdd0f5d04a773395a7 (diff) | |
i4l: fix random freezes with AVM B1 drivers
patch 9713d9e650045f7f2afd81d58a068827be306993 in mainline.
This fix the same issue which was debbuged for the C4 controller for the B1
versions.
The capilib_ function modify or traverse a linked list without locking.
This patch extends the existing locking to the calls of these function to
prevent access to a list which is in the middle of a modification.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/isdn')
| -rw-r--r-- | drivers/isdn/hardware/avm/b1.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/drivers/isdn/hardware/avm/b1.c b/drivers/isdn/hardware/avm/b1.c index 7a69a18d07e..4484a641723 100644 --- a/drivers/isdn/hardware/avm/b1.c +++ b/drivers/isdn/hardware/avm/b1.c @@ -321,12 +321,15 @@ void b1_reset_ctr(struct capi_ctr *ctrl) avmctrl_info *cinfo = (avmctrl_info *)(ctrl->driverdata); avmcard *card = cinfo->card; unsigned int port = card->port; + unsigned long flags; b1_reset(port); b1_reset(port); memset(cinfo->version, 0, sizeof(cinfo->version)); + spin_lock_irqsave(&card->lock, flags); capilib_release(&cinfo->ncci_head); + spin_unlock_irqrestore(&card->lock, flags); capi_ctr_reseted(ctrl); } @@ -361,9 +364,8 @@ void b1_release_appl(struct capi_ctr *ctrl, u16 appl) unsigned int port = card->port; unsigned long flags; - capilib_release_appl(&cinfo->ncci_head, appl); - spin_lock_irqsave(&card->lock, flags); + capilib_release_appl(&cinfo->ncci_head, appl); b1_put_byte(port, SEND_RELEASE); b1_put_word(port, appl); spin_unlock_irqrestore(&card->lock, flags); @@ -380,27 +382,27 @@ u16 b1_send_message(struct capi_ctr *ctrl, struct sk_buff *skb) u8 subcmd = CAPIMSG_SUBCOMMAND(skb->data); u16 dlen, retval; + spin_lock_irqsave(&card->lock, flags); if (CAPICMD(cmd, subcmd) == CAPI_DATA_B3_REQ) { retval = capilib_data_b3_req(&cinfo->ncci_head, CAPIMSG_APPID(skb->data), CAPIMSG_NCCI(skb->data), CAPIMSG_MSGID(skb->data)); - if (retval != CAPI_NOERROR) + if (retval != CAPI_NOERROR) { + spin_unlock_irqrestore(&card->lock, flags); return retval; + } dlen = CAPIMSG_DATALEN(skb->data); - spin_lock_irqsave(&card->lock, flags); b1_put_byte(port, SEND_DATA_B3_REQ); b1_put_slice(port, skb->data, len); b1_put_slice(port, skb->data + len, dlen); - spin_unlock_irqrestore(&card->lock, flags); } else { - spin_lock_irqsave(&card->lock, flags); b1_put_byte(port, SEND_MESSAGE); b1_put_slice(port, skb->data, len); - spin_unlock_irqrestore(&card->lock, flags); } + spin_unlock_irqrestore(&card->lock, flags); dev_kfree_skb_any(skb); return CAPI_NOERROR; @@ -534,17 +536,17 @@ irqreturn_t b1_interrupt(int interrupt, void *devptr) ApplId = (unsigned) b1_get_word(card->port); MsgLen = b1_get_slice(card->port, card->msgbuf); - spin_unlock_irqrestore(&card->lock, flags); if (!(skb = alloc_skb(MsgLen, GFP_ATOMIC))) { printk(KERN_ERR "%s: incoming packet dropped\n", card->name); + spin_unlock_irqrestore(&card->lock, flags); } else { memcpy(skb_put(skb, MsgLen), card->msgbuf, MsgLen); if (CAPIMSG_CMD(skb->data) == CAPI_DATA_B3_CONF) capilib_data_b3_conf(&cinfo->ncci_head, ApplId, CAPIMSG_NCCI(skb->data), CAPIMSG_MSGID(skb->data)); - + spin_unlock_irqrestore(&card->lock, flags); capi_ctr_handle_message(ctrl, ApplId, skb); } break; @@ -554,21 +556,17 @@ irqreturn_t b1_interrupt(int interrupt, void *devptr) ApplId = b1_get_word(card->port); NCCI = b1_get_word(card->port); WindowSize = b1_get_word(card->port); - spin_unlock_irqrestore(&card->lock, flags); - capilib_new_ncci(&cinfo->ncci_head, ApplId, NCCI, WindowSize); - + spin_unlock_irqrestore(&card->lock, flags); break; case RECEIVE_FREE_NCCI: ApplId = b1_get_word(card->port); NCCI = b1_get_word(card->port); - spin_unlock_irqrestore(&card->lock, flags); - if (NCCI != 0xffffffff) capilib_free_ncci(&cinfo->ncci_head, ApplId, NCCI); - + spin_unlock_irqrestore(&card->lock, flags); break; case RECEIVE_START: |