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Date:   Fri, 10 Apr 2020 04:48:21 +0800
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Subject: Re: [PATCH] MIPS: Limit check_bugs32() under CONFIG_32BIT
To:     "Maciej W. Rozycki" <macro@linux-mips.org>
CC:     YunQiang Su <wzssyqa@gmail.com>,
        Tiezhu Yang <yangtiezhu@loongson.cn>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-mips <linux-mips@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Xuefeng Li <lixuefeng@loongson.cn>
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-ID: <27B762B9-ABD9-495A-B9A6-74541FEB8F2F@flygoat.com>
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=E4=BA=8E 2020=E5=B9=B44=E6=9C=8810=E6=97=A5 GMT+08:00 =E4=B8=8A=E5=8D=881=
2:15:27, "Maciej W=2E Rozycki" <macro@linux-mips=2Eorg> =E5=86=99=E5=88=B0:
>On Thu, 9 Apr 2020, Jiaxun Yang wrote:
>
>> > Why is using Kconfig supposed to be better?  Several configurations
>
>> >support multiple processor types (e=2Eg=2E swappable CPU daugthercards
>or
>> >FPGA=20
>> >soft-cores) and having to list CPU types across platforms as CPUs
>are=20
>> >added is going to be a maintenance nightmare=2E  Whereas having
>> >workarounds=20
>> >or panics associated with run-time determination of the actual CPU
>type
>> >
>> >guarantees they will trigger where necessary=2E  The use of `init'
>> >sections=20
>> >assures the reclaim of memory for use after bootstrap=2E
>>=20
>> Actually I meant let bug checks depends on Kconfig's CPU selection=2E
>>=20
>> It's guaranteed that you can only select one kind of CPU one time,
>> to prevent the overhead of checking bugs on irrelevant processors=2E
>
>That makes no sense to me sorry=2E  When you select say a MIPS32r2 CPU
>for=20
>a Malta configuration, you can run it with a 4KE, 24K, 24KE, 34K, 74K,=20
>1004K, M14K, and probably a few other CPUs I have forgotten about=2E  Are
>
>you suggesting now that you want to require a separate kernel=20
>configuration for each of these CPUs?

Nope=2E As the Kconfig is telling about the possibility,
the real CPUTYPE check is still done during boot=2E

Thanks=2E
--=20
Jiaxun Yang