Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <4e312b22-73ba-8d59-b494-b7cb1d7bbb49@huawei.com>
Date:   Mon, 13 Jun 2022 18:50:45 +0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Thunderbird/91.10.0
From:   mawupeng <mawupeng1@huawei.com>
Subject: Re: [PATCH v4 5/6] mm: Only remove nomap flag for initrd
To:     <ardb@kernel.org>, <will@kernel.org>, <catalin.marinas@arm.com>
CC:     <corbet@lwn.net>, <tglx@linutronix.de>, <mingo@redhat.com>,
        <bp@alien8.de>, <dave.hansen@linux.intel.com>, <x86@kernel.org>,
        <hpa@zytor.com>, <dvhart@infradead.org>, <andy@infradead.org>,
        <rppt@kernel.org>, <akpm@linux-foundation.org>,
        <paul.walmsley@sifive.com>, <palmer@dabbelt.com>,
        <aou@eecs.berkeley.edu>, <paulmck@kernel.org>,
        <keescook@chromium.org>, <songmuchun@bytedance.com>,
        <rdunlap@infradead.org>, <damien.lemoal@opensource.wdc.com>,
        <swboyd@chromium.org>, <wei.liu@kernel.org>,
        <robin.murphy@arm.com>, <david@redhat.com>,
        <anshuman.khandual@arm.com>, <thunder.leizhen@huawei.com>,
        <wangkefeng.wang@huawei.com>, <gpiccoli@igalia.com>,
        <chenhuacai@kernel.org>, <geert@linux-m68k.org>,
        <vijayb@linux.microsoft.com>, <linux-doc@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-efi@vger.kernel.org>, <platform-driver-x86@vger.kernel.org>,
        <linux-mm@kvack.org>, <linux-riscv@lists.infradead.org>,
        <mawupeng1@huawei.com>
References: <20220613082147.183145-1-mawupeng1@huawei.com>
 <20220613082147.183145-6-mawupeng1@huawei.com>
 <CAMj1kXFn_FKt2jLJOntvT0FBtL9b=VWZdrBFpn48LBMDLy1WBQ@mail.gmail.com>
Content-Language: en-US
In-Reply-To: <CAMj1kXFn_FKt2jLJOntvT0FBtL9b=VWZdrBFpn48LBMDLy1WBQ@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 6/13/2022 5:42 PM, Ard Biesheuvel wrote:
> On Mon, 13 Jun 2022 at 10:00, Wupeng Ma <mawupeng1@huawei.com> wrote:
>>
>> From: Ma Wupeng <mawupeng1@huawei.com>
>>
>> Commit 177e15f0c144 ("arm64: add the initrd region to the linear mapping explicitly")
>> remove all the flags of the memory used by initrd. This is fine since
>> MEMBLOCK_MIRROR is not used in arm64.
>>
>> However with mirrored feature introduced to arm64, this will clear the mirrored
>> flag used by initrd, which will lead to error log printed by
>> find_zone_movable_pfns_for_nodes() if the lower 4G range has some non-mirrored
>> memory.
>>
>> To solve this problem, only MEMBLOCK_NOMAP flag will be removed via
>> memblock_clear_nomap().
>>
>> Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
> 
> Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
> 
> This needs and ack from the arm64 maintainers, please?
> And also please fix the subject to include 'arm64'
> 

Ok, I will include 'arm64' in my subject in v5.

Thanks for reviewing.

> 
>> ---
>>  arch/arm64/mm/init.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 339ee84e5a61..8456dbae9441 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -350,8 +350,8 @@ void __init arm64_memblock_init(void)
>>                         "initrd not fully accessible via the linear mapping -- please check your bootloader ...\n")) {
>>                         phys_initrd_size = 0;
>>                 } else {
>> -                       memblock_remove(base, size); /* clear MEMBLOCK_ flags */
>>                         memblock_add(base, size);
>> +                       memblock_clear_nomap(base, size);
>>                         memblock_reserve(base, size);
>>                 }
>>         }
>> --
>> 2.25.1
>>
> .