On August 18, 2021 5:11:10 PM Fabio Estevam <festevam@xxxxxxx> wrote:
When running the "hostapd" application on a i.MX7-based board with
an ath10k device connected via SDIO, the following warning is seen:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 489 at kernel/dma/mapping.c:427 dma_alloc_attrs+0xd0/0x114
Modules linked in: ath10k_sdio ath10k_core ath
CPU: 0 PID: 489 Comm: hostapd Not tainted 5.10.48-stable-standard #1
Hardware name: Freescale i.MX7 Dual (Device Tree)
[<c0111378>] (unwind_backtrace) from [<c010bc04>] (show_stack+0x10/0x14)
[<c010bc04>] (show_stack) from [<c0e26094>] (dump_stack+0xdc/0x104)
[<c0e26094>] (dump_stack) from [<c0125574>] (__warn+0xd8/0x114)
[<c0125574>] (__warn) from [<c0e20ecc>] (warn_slowpath_fmt+0x60/0xbc)
[<c0e20ecc>] (warn_slowpath_fmt) from [<c01b9eac>] (dma_alloc_attrs+0xd0/0x114)
[<c01b9eac>] (dma_alloc_attrs) from [<bf01373c>]
(ath10k_add_interface+0x2f0/0x1094 [ath10k_core])
[<bf01373c>] (ath10k_add_interface [ath10k_core]) from [<c0d94470>]
(drv_add_interface+0x88/0x2fc)
As explained by Christoph Hellwig:
"Looking at the ath10k code ar->dev is set by ath10k_core_create, which
has multiple callers.
For ath10k_pci_probe it is a pci_dev, which should always have a
dma_mask.
For ath10k_ahb_probe is a device tree probed platform_device,
which should have a dma mask.
For ath10k_sdio_probe it is a sdio_func, which from my understanding is
a virtual device can't do DMA itself.
For ath10k_snoc_probe it is a platform device with an explicit
dma_set_mask_and_coherent and above so the dma_mask is set.
For ath10k_usb_probe it is an usb device which can't do USB."
Fix the problem by not calling dma_alloc_coherent() when the device
is not DMA capable, such as SDIO and USB.
Signed-off-by: Fabio Estevam <festevam@xxxxxxx>
---
Hi,
I am not certain about the proper commit to include in the Fixes tag.
Any suggestions?
Thanks
drivers/net/wireless/ath/ath10k/mac.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff --git a/drivers/net/wireless/ath/ath10k/mac.c
b/drivers/net/wireless/ath/ath10k/mac.c
index c272b290fa73..e85c3f107d2e 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -5576,15 +5576,17 @@ static int ath10k_add_interface(struct ieee80211_hw
*hw,
if (vif->type == NL80211_IFTYPE_ADHOC ||
vif->type == NL80211_IFTYPE_MESH_POINT ||
vif->type == NL80211_IFTYPE_AP) {
- arvif->beacon_buf = dma_alloc_coherent(ar->dev,
- IEEE80211_MAX_FRAME_LEN,
- &arvif->beacon_paddr,
- GFP_ATOMIC);
- if (!arvif->beacon_buf) {
- ret = -ENOMEM;
- ath10k_warn(ar, "failed to allocate beacon buffer: %d\n",
- ret);
- goto err;
+ if (!(ar->hif.bus == ATH10K_BUS_SDIO) && !(ar->hif.bus == ATH10K_BUS_USB)) {
Does this mean you can not really setup a beaconing interface type for SDIO
and USB?
Regards,
Arend
