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SubjectRe: [PATCH] bluetooth: hci_ll: Replace mdelay with msleep in download_firmware
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Hi Jia-Ju,

> download_firmware() is never called from atomic context.
>
> It is only called by ll_setup() that is called only via function pointer
> "->setup" used in hci_uart_setup() in drivers/bluetooth/hci_serdev.c and
> drivers/bluetooth/hci_ldisc.c. hci_uart_setup() is called only
> via function pointer "->setup" used in hci_dev_do_open()
> in net/bluetooth/hci_core.c.
> All of the above functions do not enter atomic context.
>
> Besides, ll_setup() calls msleep() and hci_dev_do_open calls mutex_lock().
> So it indicates that all the above functions call functions that can sleep.
>
> Despite never getting called from atomic context, download_firmware()
> calls mdelay() for busy wait.
> That is not necessary and can be replaced with msleep to avoid busy wait.
>
> This is found by a static analysis tool named DCNS written by myself.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
> ---
> drivers/bluetooth/hci_ll.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel

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