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Subject: Re: [PATCH 5.12 regression fix resend 1/1] brcmfmac: p2p: Fix
 recently introduced deadlock issue
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     Arend van Spriel <aspriel@gmail.com>,
        Franky Lin <franky.lin@broadcom.com>,
        Hante Meuleman <hante.meuleman@broadcom.com>,
        Chi-Hsien Lin <chi-hsien.lin@infineon.com>,
        Chung-hsien Hsu <chung-hsien.hsu@infineon.com>,
        Johannes Berg <johannes.berg@intel.com>,
        linux-wireless@vger.kernel.org, brcm80211-dev-list.pdl@broadcom.com
References: <20210405205429.19304-2-hdegoede@redhat.com>
 <20210406101705.38F85C43463@smtp.codeaurora.org>
From:   Hans de Goede <hdegoede@redhat.com>
Message-ID: <5e80c41e-016c-eee5-0b23-d1b4d0d7d6b6@redhat.com>
Date:   Tue, 6 Apr 2021 12:29:14 +0200
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Hi,

On 4/6/21 12:17 PM, Kalle Valo wrote:
> Hans de Goede <hdegoede@redhat.com> wrote:
> 
>> Commit a05829a7222e ("cfg80211: avoid holding the RTNL when calling the
>> driver") replaced the rtnl_lock parameter passed to various brcmf
>> functions with just lock, because since that commit it is not just
>> about the rtnl_lock but also about the wiphy_lock .
>>
>> During this search/replace the "if (!rtnl_locked)" check in brcmfmac/p2p.c
>> was accidentally replaced with "if (locked)", dropping the inversion of
>> the check. This causes the code to now call rtnl_lock() while already
>> holding the lock, causing a deadlock.
>>
>> Add back the "!" to the if-condition to fix this.
>>
>> Cc: Johannes Berg <johannes.berg@intel.com>
>> Fixes: a05829a7222e ("cfg80211: avoid holding the RTNL when calling the driver")
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> 
> This is already applied:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers.git/commit/?id=bd83a2fc05ed323d7ae38443a6d2e253ef1c4237

But it is not yet in 5.12-rc6, even though this is a regression fix for a
regression introduced in 5.12. What is the plan to get this into 5.12 ?

Regards,

Hans