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Date:   Wed, 01 Jan 2020 20:46:40 -0800
From:   wgong@codeaurora.org
To:     Justin Capella <justincapella@gmail.com>
Cc:     ath10k <ath10k@lists.infradead.org>, linux-wireless@vger.kernel.org
Subject: Re: [PATCH v2 1/2] ath10k: add refcount for ath10k_core_restart
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On 2020-01-01 19:10, Justin Capella wrote:
> Instead of the atomic restart count, can the state be updated to
> ATH10K_STATE_RESTARTING while holding
>      mutex_unlock(&ar->conf_mutex);
> 
the recovery process is begin with ath10k_core_restart, and end with 
ath10k_reconfig_complete.
I already see it has mutex_lock(&ar->conf_mutex) and 
mutex_unlock(&ar->conf_mutex) in ath10k_core_restart,
but it is not enough, for example:
1st recovery has finished ath10k_core_restart, but not arrive 
ath10k_reconfig_complete, then the 2nd recovery
begin to enter ath10k_core_restart, it will destroy the 1st recovery and 
let 1st recovery fail.
After apply this patch, after recovery about 18000+ times, and still can 
connect/scan/ping success.

> I don't understand the bundles, but I wonder about the case when there
> are multiple packets (n_rx_pkts) and if pkt_bundle_len might be the
> one to check. Also if there needs to be a check that the len > sizeof
> HTC HDR.
> 
the htc_hdr->len is len of payload, so it allow < sizeof HTC HDR, but 
not allow > ATH10K_HTC_MBOX_MAX_PAYLOAD_LENGTH.
pkt_bundle is only used when it has many packet in rx side, otherwise it 
is not bundled in rx.

patch v3:
https://patchwork.kernel.org/patch/11313853/
https://patchwork.kernel.org/patch/11313859/

> On Tue, Dec 31, 2019 at 1:37 AM <wgong@codeaurora.org> wrote:
>> 
>> On 2019-12-25 23:14, Justin Capella wrote:
>> > This does not only effect SDIO.
>> >
>> > Why a semaphore / count? Could the conf_mutex be held earlier, or
>> > perhaps change the state to ATH10K_STATE_RESTARTING first?
>> > ath10k_reconfig_complete is also called in mac.c when channel is
>> > changed so
>> patch v2:
>> https://patchwork.kernel.org/patch/11313853/
>> https://patchwork.kernel.org/patch/11313859/