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Subject: Re: [PATCH] wifi: ath11k: initialize rx_mcs_80 and rx_mcs_160 before
 use
From: Kalle Valo <kvalo@kernel.org>
In-Reply-To: <20240202023547.11141-1-quic_bqiang@quicinc.com>
References: <20240202023547.11141-1-quic_bqiang@quicinc.com>
To: Baochen Qiang <quic_bqiang@quicinc.com>
Cc: <ath11k@lists.infradead.org>, <linux-wireless@vger.kernel.org>,
 <quic_bqiang@quicinc.com>
User-Agent: pwcli/0.1.1-git (https://github.com/kvalo/pwcli/) Python/3.11.2
Message-ID: <170715242424.1233901.13688011305726669667.kvalo@kernel.org>
Date: Mon,  5 Feb 2024 17:00:25 +0000 (UTC)

Baochen Qiang <quic_bqiang@quicinc.com> wrote:

> Currently in ath11k_peer_assoc_h_he() rx_mcs_80 and rx_mcs_160
> are used to calculate max_nss, see
>         if (support_160)
>                 max_nss = min(rx_mcs_80, rx_mcs_160);
>         else
>                 max_nss = rx_mcs_80;
> 
> Kernel test robot complains on uninitialized symbols:
> drivers/net/wireless/ath/ath11k/mac.c:2321 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'.
> drivers/net/wireless/ath/ath11k/mac.c:2321 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_160'.
> drivers/net/wireless/ath/ath11k/mac.c:2323 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'.
> 
> This is because there are some code paths that never set them, so
> the assignment of max_nss can come from uninitialized variables.
> This could result in some unknown issues since a wrong peer_nss
> might be passed to firmware.
> 
> Change to initialize them to an invalid value at the beginning. This
> makes sense because even max_nss gets an invalid value, due to either
> or both of them being invalid, we can get an valid peer_nss with
> following guard:
>         arg->peer_nss = min(sta->deflink.rx_nss, max_nss)
> 
> Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23
> 
> Fixes: 3db26ecf7114 ("ath11k: calculate the correct NSS of peer for HE capabilities")
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202401311243.NyXwWZxP-lkp@intel.com/
> Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
> Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

b802e7b7e771 wifi: ath11k: initialize rx_mcs_80 and rx_mcs_160 before use

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20240202023547.11141-1-quic_bqiang@quicinc.com/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches