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Date:   Tue, 26 Jul 2022 22:42:40 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Chris Murphy <lists@colorremedies.com>
Cc:     David Sterba <dsterba@suse.cz>,
        =?utf-8?B?0JzQuNGF0LDQuNC7INCT0LDQstGA0LjQu9C+0LI=?= 
        <mikhail.v.gavrilov@gmail.com>,
        Btrfs BTRFS <linux-btrfs@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
Message-ID: <20220726204240.GM13489@twin.jikos.cz>
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        Btrfs BTRFS <linux-btrfs@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Tue, Jul 26, 2022 at 03:21:32PM -0400, Chris Murphy wrote:
> 
> 
> On Tue, Jul 26, 2022, at 3:19 PM, Chris Murphy wrote:
> > On Tue, Jul 26, 2022, at 12:42 PM, David Sterba wrote:
> >> On Tue, Jul 26, 2022 at 05:32:54PM +0500, Mikhail Gavrilov wrote:
> >>> Hi guys.
> >>> Always with intensive writing on a btrfs volume, the message "BUG:
> >>> MAX_LOCKDEP_CHAIN_HLOCKS too low!" appears in the kernel logs.
> >>
> >> Increase the config value of LOCKDEP_CHAINS_BITS, default is 16, 18
> >> tends to work.
> >
> > Fedora is using 17. I'll make a request to bump it to 18. Thanks.
> 
> Should it be 18 across all archs? Or is it OK to only bump x86_64?

I think it applies to all achritectures equally but I'm no lockdep
expert.