Re: [rt2x00-users] ieee80211_tx_status: headroom too small

From: Gertjan van Wingerde
Date: Sun Nov 22 2009 - 07:47:25 EST


On 11/22/09 08:09, David Ellingsworth wrote:
> On Sat, Nov 21, 2009 at 10:27 AM, Gertjan van Wingerde
> <gwingerde@xxxxxxxxx> wrote:
>> On 11/21/09 02:30, David Ellingsworth wrote:
>>> Wasn't sure where to send this, but with the latest 2.6.32-rc8-wl
>>> kernel built from the wireless-testing repository I'm getting a number
>>> of "ieee80211_tx_status: headroom too small" errors in my syslog. I'm
>>> using the rt61pci driver in conjunction with hostap as a wpa2 secured
>>> access point. The relevant information about my card from lspci is:
>>>
>>> 01:08.0 0280: 1814:0301
>>> Subsystem: 1458:e934
>>> Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop-
>>> ParErr- Stepping- SERR+ FastB2B- DisINTx-
>>> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=slow >TAbort-
>>> <TAbort- <MAbort- >SERR- <PERR- INTx-
>>> Latency: 64, Cache Line Size: 128 bytes
>>> Interrupt: pin A routed to IRQ 18
>>> Region 0: Memory at fe6f0000 (32-bit, non-prefetchable) [size=32K]
>>> Capabilities: [40] Power Management version 2
>>> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
>>> PME(D0-,D1-,D2-,D3hot-,D3cold-)
>>> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>>> Kernel driver in use: rt61pci
>>>
>>> If you need any other information, I'll be happy to provide it.
>>>
>>
>> Hi David,
>>
>> This seems to be caused by the rt2x00 driver not properly declaring its alignment
>> maneuvring space properly, and thus it doesn't leave enough headroom left for
>> copying to the monitor interface.
>>
>> Can you check whether the attached patch fixes the issue for you?
>> Note: patch looks a bit bigger than it actually is due to indenting cleanups.
>>
>
> Gertjan,
>
> I haven't really been able to test this. The kernel version I was
> using at the time was 2.6.32-rc7-wl and not 2.6.32-rc8-wl. I'm rather
> certain the patch will resolve the issue, but I've been unable to get
> my wireless card to function properly with the latest 2.6.32-rc8-wl
> master branch. I'm not entirely sure what changed since two days ago,
> but I know the following:
>
> 1. 2.6.32-rc8 from Linus' master branch works fine but still exhibits
> this issue. However, this patch will not apply on top of 2.6.32-rc8.
>
> 2. 2.6.32-rc7-wl(11/19/2009) worked fine with the exception of the
> above mentioned error. Unable to test patch since I pulled all the
> recent modifications down.
> 3. 2.6.32-rc8-wl does not work at all for me, but patch does apply.
>
> I'm not entirely sure what the differences are between Linus' master
> branch of 2.6.32-rc8 and the current 2.6.32-rc8-wl tree are or what
> changes have been made on the wireless-testing master branch in the
> last couple of days that are preventing me from fully testing this
> patch.
>
> With the current wireless-testing master branch, 2.6.32-rc8-wl, with
> and without the patch I can associate and authenticate with my AP but
> am unable to do anything else. Any attempt to establish a wireless
> connection thus dies while trying to obtain an ip address via DHCP.
> Sadly, no errors are logged indicating what the cause of this problem
> might be. Given that I've only seen these errors after establishing a
> wireless connection, it's a little difficult for me to test without
> being able to transmit any data.
>
> I don't know if it's worth the effort or not, but if this patch were
> re-based against Linus' master branch I might be able to test it since
> my AP at least works with 2.6.32-rc8.

David,

OK. Find attached the patch ported to Linus' tree. It should apply to
any version of Linus' tree after 2.6.32-rc8.
I think it is good to get real confirmation that the patch behaves
as expected.

---
Gertjan.


diff --git a/drivers/net/wireless/rt2x00/rt2400pci.c b/drivers/net/wireless/rt2x00/rt2400pci.c
index 798f625..7a8b2c4 100644
--- a/drivers/net/wireless/rt2x00/rt2400pci.c
+++ b/drivers/net/wireless/rt2x00/rt2400pci.c
@@ -1431,7 +1431,8 @@ static int rt2400pci_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;
- rt2x00dev->hw->extra_tx_headroom = 0;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom +
+ RT2X00_ALIGN_SIZE;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -1622,20 +1623,21 @@ static const struct data_queue_desc rt2400pci_queue_atim = {
};

static const struct rt2x00_ops rt2400pci_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 1,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt2400pci_queue_rx,
- .tx = &rt2400pci_queue_tx,
- .bcn = &rt2400pci_queue_bcn,
- .atim = &rt2400pci_queue_atim,
- .lib = &rt2400pci_rt2x00_ops,
- .hw = &rt2400pci_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 1,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = 0,
+ .rx = &rt2400pci_queue_rx,
+ .tx = &rt2400pci_queue_tx,
+ .bcn = &rt2400pci_queue_bcn,
+ .atim = &rt2400pci_queue_atim,
+ .lib = &rt2400pci_rt2x00_ops,
+ .hw = &rt2400pci_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt2400pci_rt2x00debug,
+ .debugfs = &rt2400pci_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

diff --git a/drivers/net/wireless/rt2x00/rt2500pci.c b/drivers/net/wireless/rt2x00/rt2500pci.c
index 2e872ac..0baa5a7 100644
--- a/drivers/net/wireless/rt2x00/rt2500pci.c
+++ b/drivers/net/wireless/rt2x00/rt2500pci.c
@@ -1732,7 +1732,8 @@ static int rt2500pci_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;

- rt2x00dev->hw->extra_tx_headroom = 0;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom +
+ RT2X00_ALIGN_SIZE;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -1921,20 +1922,21 @@ static const struct data_queue_desc rt2500pci_queue_atim = {
};

static const struct rt2x00_ops rt2500pci_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 1,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt2500pci_queue_rx,
- .tx = &rt2500pci_queue_tx,
- .bcn = &rt2500pci_queue_bcn,
- .atim = &rt2500pci_queue_atim,
- .lib = &rt2500pci_rt2x00_ops,
- .hw = &rt2500pci_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 1,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = 0,
+ .rx = &rt2500pci_queue_rx,
+ .tx = &rt2500pci_queue_tx,
+ .bcn = &rt2500pci_queue_bcn,
+ .atim = &rt2500pci_queue_atim,
+ .lib = &rt2500pci_rt2x00_ops,
+ .hw = &rt2500pci_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt2500pci_rt2x00debug,
+ .debugfs = &rt2500pci_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index 22dd6d9..1416f32 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -1788,7 +1788,7 @@ static int rt2500usb_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;

- rt2x00dev->hw->extra_tx_headroom = TXD_DESC_SIZE;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -1956,20 +1956,21 @@ static const struct data_queue_desc rt2500usb_queue_atim = {
};

static const struct rt2x00_ops rt2500usb_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 1,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt2500usb_queue_rx,
- .tx = &rt2500usb_queue_tx,
- .bcn = &rt2500usb_queue_bcn,
- .atim = &rt2500usb_queue_atim,
- .lib = &rt2500usb_rt2x00_ops,
- .hw = &rt2500usb_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 1,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = TXD_DESC_SIZE,
+ .rx = &rt2500usb_queue_rx,
+ .tx = &rt2500usb_queue_tx,
+ .bcn = &rt2500usb_queue_bcn,
+ .atim = &rt2500usb_queue_atim,
+ .lib = &rt2500usb_rt2x00_ops,
+ .hw = &rt2500usb_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt2500usb_rt2x00debug,
+ .debugfs = &rt2500usb_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index 9fe770f..19298ef 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -2509,7 +2509,8 @@ static int rt2800usb_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;
- rt2x00dev->hw->extra_tx_headroom = TXINFO_DESC_SIZE + TXWI_DESC_SIZE;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom +
+ RT2X00_L2PAD_SIZE;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -2852,19 +2853,20 @@ static const struct data_queue_desc rt2800usb_queue_bcn = {
};

static const struct rt2x00_ops rt2800usb_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 8,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt2800usb_queue_rx,
- .tx = &rt2800usb_queue_tx,
- .bcn = &rt2800usb_queue_bcn,
- .lib = &rt2800usb_rt2x00_ops,
- .hw = &rt2800usb_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 8,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = TXINFO_DESC_SIZE + TXWI_DESC_SIZE,
+ .rx = &rt2800usb_queue_rx,
+ .tx = &rt2800usb_queue_tx,
+ .bcn = &rt2800usb_queue_bcn,
+ .lib = &rt2800usb_rt2x00_ops,
+ .hw = &rt2800usb_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt2800usb_rt2x00debug,
+ .debugfs = &rt2800usb_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 27bc6b7..a71962e 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -112,6 +112,12 @@
( ((unsigned long)((__skb)->data + (__header))) & 3 )

/*
+ * Constants for extra TX headroom for alignment purposes.
+ */
+#define RT2X00_ALIGN_SIZE 4
+#define RT2X00_L2PAD_SIZE 8
+
+/*
* Standard timing and size defines.
* These values should follow the ieee80211 specifications.
*/
@@ -579,6 +585,7 @@ struct rt2x00_ops {
const unsigned int eeprom_size;
const unsigned int rf_size;
const unsigned int tx_queues;
+ const unsigned int extra_tx_headroom;
const struct data_queue_desc *rx;
const struct data_queue_desc *tx;
const struct data_queue_desc *bcn;
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index 577029e..2ec9c14 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -103,7 +103,7 @@ void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
* is also mapped to the DMA so it can be used for transfering
* additional descriptor information to the hardware.
*/
- skb_push(skb, rt2x00dev->hw->extra_tx_headroom);
+ skb_push(skb, rt2x00dev->ops->extra_tx_headroom);

skbdesc->skb_dma =
dma_map_single(rt2x00dev->dev, skb->data, skb->len, DMA_TO_DEVICE);
@@ -111,7 +111,7 @@ void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
/*
* Restore data pointer to original location again.
*/
- skb_pull(skb, rt2x00dev->hw->extra_tx_headroom);
+ skb_pull(skb, rt2x00dev->ops->extra_tx_headroom);

skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
}
@@ -133,7 +133,7 @@ void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
* by the driver, but it was actually mapped to DMA.
*/
dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma,
- skb->len + rt2x00dev->hw->extra_tx_headroom,
+ skb->len + rt2x00dev->ops->extra_tx_headroom,
DMA_TO_DEVICE);
skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
}
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index b20e3ea..7b6f056 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -2545,7 +2545,8 @@ static int rt61pci_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;
- rt2x00dev->hw->extra_tx_headroom = 0;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom +
+ RT2X00_ALIGN_SIZE;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -2787,19 +2788,20 @@ static const struct data_queue_desc rt61pci_queue_bcn = {
};

static const struct rt2x00_ops rt61pci_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 4,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt61pci_queue_rx,
- .tx = &rt61pci_queue_tx,
- .bcn = &rt61pci_queue_bcn,
- .lib = &rt61pci_rt2x00_ops,
- .hw = &rt61pci_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 4,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = 0,
+ .rx = &rt61pci_queue_rx,
+ .tx = &rt61pci_queue_tx,
+ .bcn = &rt61pci_queue_bcn,
+ .lib = &rt61pci_rt2x00_ops,
+ .hw = &rt61pci_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt61pci_rt2x00debug,
+ .debugfs = &rt61pci_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 14e7bb2..9f733e1 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -2068,7 +2068,7 @@ static int rt73usb_probe_hw_mode(struct rt2x00_dev *rt2x00dev)
IEEE80211_HW_SIGNAL_DBM |
IEEE80211_HW_SUPPORTS_PS |
IEEE80211_HW_PS_NULLFUNC_STACK;
- rt2x00dev->hw->extra_tx_headroom = TXD_DESC_SIZE;
+ rt2x00dev->hw->extra_tx_headroom = rt2x00dev->ops->extra_tx_headroom;

SET_IEEE80211_DEV(rt2x00dev->hw, rt2x00dev->dev);
SET_IEEE80211_PERM_ADDR(rt2x00dev->hw,
@@ -2305,19 +2305,20 @@ static const struct data_queue_desc rt73usb_queue_bcn = {
};

static const struct rt2x00_ops rt73usb_ops = {
- .name = KBUILD_MODNAME,
- .max_sta_intf = 1,
- .max_ap_intf = 4,
- .eeprom_size = EEPROM_SIZE,
- .rf_size = RF_SIZE,
- .tx_queues = NUM_TX_QUEUES,
- .rx = &rt73usb_queue_rx,
- .tx = &rt73usb_queue_tx,
- .bcn = &rt73usb_queue_bcn,
- .lib = &rt73usb_rt2x00_ops,
- .hw = &rt73usb_mac80211_ops,
+ .name = KBUILD_MODNAME,
+ .max_sta_intf = 1,
+ .max_ap_intf = 4,
+ .eeprom_size = EEPROM_SIZE,
+ .rf_size = RF_SIZE,
+ .tx_queues = NUM_TX_QUEUES,
+ .extra_tx_headroom = TXD_DESC_SIZE,
+ .rx = &rt73usb_queue_rx,
+ .tx = &rt73usb_queue_tx,
+ .bcn = &rt73usb_queue_bcn,
+ .lib = &rt73usb_rt2x00_ops,
+ .hw = &rt73usb_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
- .debugfs = &rt73usb_rt2x00debug,
+ .debugfs = &rt73usb_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};