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Subject: Re: [PATCH] iwlwifi: Fix softirq/hardirq disabling in
 iwl_pcie_gen2_enqueue_hcmd()
To:     Johannes Berg <johannes@sipsolutions.net>,
        Luca Coelho <luciano.coelho@intel.com>,
        Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Cc:     Kalle Valo <kvalo@codeaurora.org>, linux-wireless@vger.kernel.org,
        Jiri Kosina <jkosina@suse.cz>,
        Chris Murphy <lists@colorremedies.com>
References: <20210415120447.4424-1-hdegoede@redhat.com>
 <c70da4aa428625b5261f9f7dbb3904d81a54e694.camel@sipsolutions.net>
From:   Hans de Goede <hdegoede@redhat.com>
Message-ID: <b679efa9-de92-d9c0-d003-ddb3f737ca32@redhat.com>
Date:   Thu, 15 Apr 2021 17:32:08 +0200
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Hi,

On 4/15/21 2:21 PM, Johannes Berg wrote:
> On Thu, 2021-04-15 at 14:04 +0200, Hans de Goede wrote:
>> This fixes the same locking problem fixed by commit 2800aadc18a6 ("iwlwifi:
>> Fix softirq/hardirq disabling in iwl_pcie_enqueue_hcmd()") but then for
>> the gen2 variant of enqueue_hcmd().
>>
>> It's possible for iwl_pcie_enqueue_hcmd() to be called with hard IRQs
>> disabled (e.g. from LED core). We can't enable BHs in such a situation.
>>
>> Turn the unconditional BH-enable/BH-disable code into
>> hardirq-disable/conditional-enable.
>>
>> This fixes the warning below.
> 
> I believe Jiri posted the same patch:
> 
> https://lore.kernel.org/linux-wireless/nycvar.YFH.7.76.2104070918090.12405@cbobk.fhfr.pm/

Ah yes that is the same patch. I did reference Jiri's patch
for fixing the same issue in iwl_pcie_enqueue_hcmd() in the commit
message, without knowing that Jiri had send a later patch which also fixes
this in  iwl_pcie_gen2_enqueue_hcmd().

Going with Jiri's patch is fine then, but it would be nice if we
can get a fix for this in place soon-ish, which I see has
already been discussed further down in this thread :)

Regards,

Hans