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Date:   Tue, 8 Nov 2022 08:04:51 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Wei Yongjun <weiyongjun1@huawei.com>
Cc:     Qi Zheng <zhengqi.arch@bytedance.com>, dvyukov@google.com,
        willy@infradead.org, akinobu.mita@gmail.com,
        akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        stable@vger.kernel.org
Subject: Re: [PATCH v2] mm: fix unexpected changes to
 {failslab|fail_page_alloc}.attr
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On Tue, Nov 08, 2022 at 05:32:52PM +0800, Wei Yongjun wrote:
> > So you want to set/clear this no_warn attr through the procfs or sysfs
> > interface, so that you can easily disable/enable the slab/page fault
> > warning message from the user mode. Right?
> 
> Yes, just like:
> 
> echo 1 > /sys/kernel/debug/failslab/no_warn  #disable message
> echo 0 > /sys/kernel/debug/failslab/no_warn  #enable message

You can already do that:

 echo 0 > /sys/kernel/debug/failslab/verbose  #disable message

Jason