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From:   Guilherme Piccoli <gpiccoli@canonical.com>
Date:   Fri, 11 Oct 2019 20:41:31 -0300
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Subject: Re: [PATCH] hugetlb: Add nohugepages parameter to prevent hugepages creation
To:     Qian Cai <cai@lca.pw>
Cc:     linux-mm@kvack.org, mike.kravetz@oracle.com,
        linux-kernel@vger.kernel.org,
        Jay Vosburgh <jay.vosburgh@canonical.com>,
        "Guilherme G. Piccoli" <kernel@gpiccoli.net>
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On Fri, Oct 11, 2019 at 8:36 PM Qian Cai <cai@lca.pw> wrote:
>
> Typically, kdump kernel has its own initramfs, and don’t even need to mount a rootfs, so I can’t see how sysfs/sysctl is relevant here.

Thanks for the quick response. Kdump in Ubuntu, for example, rely in
mounting the root filesystem.
Even in initrd-only approaches, we could have sysctl.conf being copied
to initramfs, and hugepages end-up getting set.

Also, I don't think the "nohugepages" is useful only for kdump - I
found odd we cannot prevent the creation of hugepages at all when
using sysfs writes.

Cheers,


Guilherme