linux-kernel - Re: [PATCH v2 2/3] riscv: End kernel region search in setup

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Date:   Sun, 16 Feb 2020 17:06:00 +0100
From:   Jan Kiszka <jan.kiszka@....de>
To:     Alex Ghiti <alex@...ti.fr>,
        Paul Walmsley <paul.walmsley@...ive.com>,
        Palmer Dabbelt <palmer@...belt.com>,
        Albert Ou <aou@...s.berkeley.edu>,
        linux-riscv@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/3] riscv: End kernel region search in setup_bootmem
 earlier

On 16.02.20 15:42, Alex Ghiti wrote:
> Hi Jan,
>
> On 2/15/20 6:49 AM, Jan Kiszka wrote:
>> From: Jan Kiszka <jan.kiszka@...mens.com>
>>
>> No need to look further when that single region is found.
>>
>> Signed-off-by: Jan Kiszka <jan.kiszka@...mens.com>
>> =2D--
>>   arch/riscv/mm/init.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
>> index aec39a56d6cf..a774547e9021 100644
>> =2D-- a/arch/riscv/mm/init.c
>> +++ b/arch/riscv/mm/init.c
>> @@ -160,6 +160,8 @@ void __init setup_bootmem(void)
>>               if (reg->base + mem_size < end)
>>                   memblock_remove(reg->base + mem_size,
>>                           end - reg->base - mem_size);
>> +
>> +            break;
>>           }
>>       }
>>       BUG_ON(mem_size =3D=3D 0);
>> =2D-
>> 2.16.4
>>
>>
>
> I was looking at the test above that determines if the current memblock
> contains the kernel:
>
> if (reg->base <= vmlinux_end && vmlinux_end <= end)
>
> Shouldn't it be:
>
> if (reg->base <= vmlinux_start && vmlinux_end <= end)
>
> ?

Yes, I think you are right. Would you like to send a patch that fixes this?

>
> Otherwise, we can indeed stop as soon as we found the region containing
> the kernel, so feel free to add:
>
> Reviewed-by: Alexandre Ghiti <alex@...ti.fr>
>

Thanks,
Jan