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Message-ID: <c0874b06-116d-7471-3b50-21099c729c3d@gmail.com>
Date:   Wed, 16 Mar 2022 11:43:30 +0100
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Subject: Re: [PATCH] ath11k: acquire ab->base_lock in unassign when finding
 the peer by addr
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To:     Kalle Valo <kvalo@kernel.org>
Cc:     ath11k@lists.infradead.org, linux-wireless@vger.kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Carl Huang <cjhuang@codeaurora.org>
References: <20220314215253.92658-1-dossche.niels@gmail.com>
 <87o826pgqr.fsf@kernel.org>
From:   Niels Dossche <dossche.niels@gmail.com>
In-Reply-To: <87o826pgqr.fsf@kernel.org>
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On 3/16/22 07:13, Kalle Valo wrote:
> Niels Dossche <dossche.niels@gmail.com> writes:
> 
>> ath11k_peer_find_by_addr states via lockdep that ab->base_lock must be
>> held when calling that function in order to protect the list. All
>> callers except ath11k_mac_op_unassign_vif_chanctx have that lock
>> acquired when calling ath11k_peer_find_by_addr. That lock is also not
>> transitively held by a path towards ath11k_mac_op_unassign_vif_chanctx.
>> The solution is to acquire the lock when calling
>> ath11k_peer_find_by_addr inside ath11k_mac_op_unassign_vif_chanctx.
>>
>> Fixes: 701e48a43e15 ("ath11k: add packet log support for QCA6390")
>> Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
> 
> On what hardware and firmware version did you test this?
> 

Hi Kalle

Thanks for your reply.
I am currently working on a static analyser to detect missing locks.
This was a reported case. I manually verified the report by looking
at the code, so that I do not send wrong information or patches.
After concluding that this seems to be a true positive, I created this patch.
However, as I do not in fact have this particular hardware, I was unable to test it.

Thanks