Re: [PATCH v1] usb: musb: dsps: set MUSB_DA8XX quirk for AM335x

[Bin Liu]

Hi,

On Fri, Mar 27, 2020 at 06:38:49AM +0100, Oleksij Rempel wrote:
> Beagle Bone Black has different memory corruptions if kernel is
> configured with USB_TI_CPPI41_DMA=y. This issue is reproducible with
> ath9k-htc driver (ar9271 based wifi usb controller):
> 
> root@AccessBox:~ iw dev wlan0 set monitor  fcsfail otherbss
> root@AccessBox:~ ip l s dev wlan0 up
> kmemleak: Cannot insert 0xda577e40 into the object search tree (overlaps existing)
> CPU: 0 PID: 176 Comm: ip Not tainted 5.5.0 #7
> Hardware name: Generic AM33XX (Flattened Device Tree)
> [<c0112c14>] (unwind_backtrace) from [<c010dc98>] (show_stack+0x18/0x1c)
> [<c010dc98>] (show_stack) from [<c08c7c2c>] (dump_stack+0x84/0x98)
> [<c08c7c2c>] (dump_stack) from [<c02c75a8>] (create_object+0x2f8/0x324)
> [<c02c75a8>] (create_object) from [<c02b8928>] (kmem_cache_alloc+0x1a8/0x39c)
> [<c02b8928>] (kmem_cache_alloc) from [<c072fb68>] (__alloc_skb+0x60/0x174)
> [<c072fb68>] (__alloc_skb) from [<bf0c5c58>] (ath9k_wmi_cmd+0x50/0x184 [ath9k_htc])
> [<bf0c5c58>] (ath9k_wmi_cmd [ath9k_htc]) from [<bf0cb410>] (ath9k_regwrite_multi+0x54/0x84 [ath9k_htc])
> [<bf0cb410>] (ath9k_regwrite_multi [ath9k_htc]) from [<bf0cb7fc>] (ath9k_regwrite+0xf0/0xfc [ath9k_htc])
> [<bf0cb7fc>] (ath9k_regwrite [ath9k_htc]) from [<bf1aca78>] (ar5008_hw_process_ini+0x280/0x6c0 [ath9k_hw])
> [<bf1aca78>] (ar5008_hw_process_ini [ath9k_hw]) from [<bf1a66ac>] (ath9k_hw_reset+0x270/0x1458 [ath9k_hw])
> [<bf1a66ac>] (ath9k_hw_reset [ath9k_hw]) from [<bf0c9588>] (ath9k_htc_start+0xb0/0x22c [ath9k_htc])
> [<bf0c9588>] (ath9k_htc_start [ath9k_htc]) from [<bf0eb3c0>] (drv_start+0x4c/0x1e8 [mac80211])
> [<bf0eb3c0>] (drv_start [mac80211]) from [<bf104a84>] (ieee80211_do_open+0x480/0x954 [mac80211])
> [<bf104a84>] (ieee80211_do_open [mac80211]) from [<c075127c>] (__dev_open+0xdc/0x160)
> [<c075127c>] (__dev_open) from [<c07516a8>] (__dev_change_flags+0x1a4/0x204)
> [<c07516a8>] (__dev_change_flags) from [<c0751728>] (dev_change_flags+0x20/0x50)
> [<c0751728>] (dev_change_flags) from [<c076971c>] (do_setlink+0x2ac/0x978)
> 
> After applying this patch, the system is running in monitor mode without
> noticeable issues.
> 
> Suggested-by: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> ---
>  drivers/usb/musb/musb_dsps.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
> index 88923175f71e..c01f9e9e69f5 100644
> --- a/drivers/usb/musb/musb_dsps.c
> +++ b/drivers/usb/musb/musb_dsps.c
> @@ -690,7 +690,7 @@ static void dsps_dma_controller_resume(struct dsps_glue *glue) {}
>  #endif /* CONFIG_USB_TI_CPPI41_DMA */
>  
>  static struct musb_platform_ops dsps_ops = {
> -	.quirks		= MUSB_DMA_CPPI41 | MUSB_INDEXED_EP,
> +	.quirks		= MUSB_DMA_CPPI41 | MUSB_INDEXED_EP | MUSB_DA8XX,

The MUSB_DA8XX flag cannot be simply applied to MUSB_DSPS, at least the
teardown and autoreq register offsets are different as show in
cppi41_dma_controller_create().

Do you understand what exactly caused the issue? The kernel trace above
doesn't provide enuough information.

-Bin.