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Subject: Re: [PATCHv2 1/1] ext4: mballoc: Use this_cpu_read instead of
 this_cpu_ptr
To:     Christoph Hellwig <hch@infradead.org>, tytso@mit.edu
Cc:     linux-ext4@vger.kernel.org, jack@suse.com,
        Hillf Danton <hdanton@sina.com>, linux-fsdevel@vger.kernel.org,
        Borislav Petkov <bp@alien8.de>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        syzbot+82f324bb69744c5f6969@syzkaller.appspotmail.com
References: <534f275016296996f54ecf65168bb3392b6f653d.1591699601.git.riteshh@linux.ibm.com>
 <20200610062538.GA24975@infradead.org>
From:   Ritesh Harjani <riteshh@linux.ibm.com>
Date:   Wed, 10 Jun 2020 12:04:31 +0530
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On 6/10/20 11:55 AM, Christoph Hellwig wrote:
> On Tue, Jun 09, 2020 at 04:23:10PM +0530, Ritesh Harjani wrote:
>> Simplify reading a seq variable by directly using this_cpu_read API
>> instead of doing this_cpu_ptr and then dereferencing it.
>>
>> This also avoid the below kernel BUG: which happens when
>> CONFIG_DEBUG_PREEMPT is enabled
> 
> I see this warning all the time with ext4 using tests VMs, so lets get
> this fixed ASAP before -rc1:

Couldn't agree more.

> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> 

Thanks

-ritesh