Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 24 Feb 2021 14:35:48 +0000
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Chen Zhou <chenzhou10@huawei.com>
Cc:     mingo@redhat.com, tglx@linutronix.de, rppt@kernel.org,
        dyoung@redhat.com, bhe@redhat.com, will@kernel.org,
        nsaenzjulienne@suse.de, corbet@lwn.net, John.P.donnelly@oracle.com,
        bhsharma@redhat.com, prabhakar.pkin@gmail.com, horms@verge.net.au,
        robh+dt@kernel.org, arnd@arndb.de, james.morse@arm.com,
        xiexiuqi@huawei.com, guohanjun@huawei.com, huawei.libin@huawei.com,
        wangkefeng.wang@huawei.com, linux-doc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        kexec@lists.infradead.org
Subject: Re: [PATCH v14 02/11] x86: kdump: make the lower bound of crash
 kernel reservation consistent
Message-ID: <20210224143547.GB28965@arm.com>
References: <20210130071025.65258-1-chenzhou10@huawei.com>
 <20210130071025.65258-3-chenzhou10@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210130071025.65258-3-chenzhou10@huawei.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

On Sat, Jan 30, 2021 at 03:10:16PM +0800, Chen Zhou wrote:
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index da769845597d..27470479e4a3 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -439,7 +439,8 @@ static int __init reserve_crashkernel_low(void)
>  			return 0;
>  	}
>  
> -	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
> +	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, CRASH_ALIGN,
> +			CRASH_ADDR_LOW_MAX);
>  	if (!low_base) {
>  		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
>  		       (unsigned long)(low_size >> 20));

Is there any reason why the lower bound can't be 0 in all low cases
here? (Sorry if it's been already discussed, I lost track)

-- 
Catalin