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Date:   Mon, 7 Nov 2022 08:42:43 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Qi Zheng <zhengqi.arch@bytedance.com>
Cc:     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] mm: fix unexpected changes to
 {failslab|fail_page_alloc}.attr
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On Mon, Nov 07, 2022 at 11:31:09AM +0800, Qi Zheng wrote:

> @@ -31,9 +33,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
>  		return false;
>  
>  	if (gfpflags & __GFP_NOWARN)
> -		failslab.attr.no_warn = true;
> +		flags |= FAULT_NOWARN;

You should add a comment here about why this is required, to avoid
deadlocking printk

Jason