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From:   Nick Terrell <terrelln@fb.com>
To:     Arvind Sankar <nivedita@alum.mit.edu>
CC:     Sedat Dilek <sedat.dilek@gmail.com>,
        Nick Terrell <nickrterrell@gmail.com>,
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Subject: Re: [PATCH v8 6/7] x86: Add support for ZSTD compressed kernel
Thread-Topic: [PATCH v8 6/7] x86: Add support for ZSTD compressed kernel
Thread-Index: AQHWYSfJcwxv6ZmoP0i5UtMjZQMfxakV5pAAgADlDQCABUEVAA==
Date:   Mon, 27 Jul 2020 22:44:37 +0000
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> On Jul 24, 2020, at 7:30 AM, Arvind Sankar <nivedita@alum.mit.edu> wrote:
>=20
> On Fri, Jul 24, 2020 at 02:50:34AM +0200, Sedat Dilek wrote:
>> On Thu, Jul 23, 2020 at 9:30 PM Nick Terrell <nickrterrell@gmail.com> wr=
ote:
>>>=20
>>> From: Nick Terrell <terrelln@fb.com>
>>>=20
>>> * Add support for zstd compressed kernel
>>> * Define __DISABLE_EXPORTS in misc.c
>>> * Bump the heap size for zstd.
>>> * Update the documentation.
>>>=20
>>> Integrates the ZSTD decompression code to the x86 pre-boot code.
>>>=20
>>> Zstandard requires slightly more memory during the kernel decompression
>>> on x86 (192 KB vs 64 KB), and the memory usage is independent of the
>>> window size.
>>>=20
>>> __DISABLE_EXPORTS is defined in misc.c instead of the Makefile because
>>> kaslr.c defines __DISABLE_EXPORTS, and defining it in the Makefile give=
s
>>> duplicate definition warnings.
>>>=20
>>=20
>> That was reported by Arvind - feel free to add a Reported-by: ...
>>=20
>> - Sedat -
>>=20
>=20
> It's not necessary to add Reported-by's for problems encountered while
> developing the series. Especially as it was my drive-by suggestion to
> use __DISABLE_EXPORTS that introduced the issue in the first place :)
>=20
> I'd have added it to the Makefile and just dropped the definition in
> kaslr.c -- should be no reason for anything in here to use EXPORT_SYMBOL.

Sure, I was a bit hesitant to modify more than necessary here, but I will g=
o
ahead and do that.

Thanks for the reviews!=