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

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Date:   Sun, 16 Feb 2020 14:57:04 -0500
From:   Alex Ghiti <alex@...ti.fr>
To:     Jan Kiszka <jan.kiszka@....de>,
        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 2/16/20 11:06 AM, Jan Kiszka wrote:
> 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?

Thanks for confirming, I'll send a patch tomorrow and cc stable too.

Alex

> 
>>
>> 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
>