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Date:   Mon, 30 May 2022 14:31:52 +0100
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Peter Xu <peterx@redhat.com>
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Subject: Re: [PATCH v4] mm: Avoid unnecessary page fault retires on shared
 memory types
Message-ID: <YpTHSNQxzQxwJ4vQ@arm.com>
References: <20220527193936.30678-1-peterx@redhat.com>
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On Fri, May 27, 2022 at 03:39:36PM -0400, Peter Xu wrote:
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index 77341b160aca..e401d416bbd6 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -607,6 +607,10 @@ static int __kprobes do_page_fault(unsigned long far, unsigned int esr,
>  		return 0;
>  	}
>  
> +	/* The fault is fully completed (including releasing mmap lock) */
> +	if (fault & VM_FAULT_COMPLETED)
> +		return 0;
> +
>  	if (fault & VM_FAULT_RETRY) {
>  		mm_flags |= FAULT_FLAG_TRIED;
>  		goto retry;

For arm64:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>