Date:   Tue, 7 Feb 2023 18:21:20 +0000
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Kaihao Bai <carlo.bai@linux.alibaba.com>
Cc:     will@kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, anshuman.khandual@arm.com,
        baolin.wang@linux.alibaba.com
Subject: Re: [RFC PATCH 1/1] arm64: mm: remove unnecessary multiple tlb flush
 of contiguous hugetlb
Message-ID: <Y+KWoDw1ppliQ5Sg@arm.com>
References: <1675768181-41518-1-git-send-email-carlo.bai@linux.alibaba.com>
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On Tue, Feb 07, 2023 at 07:09:41PM +0800, Kaihao Bai wrote:
> In arm64, contiguous flag refers to the same TLB entry that shared by a
> contiguous address range. If flush one entry of the address range, it
> would cover the whole contiguous address range. Thus there's no need to
> flush all contiguous range that CONT_PMD/PTE points to.

This doesn't work. The contiguous bit is a hint, so the CPU may not
coalesce multiple PTEs into a single TLB entry.

-- 
Catalin