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From:   Benjamin Coddington <bcodding@redhat.com>
To:     Nicholas Piggin <npiggin@gmail.com>
Cc:     linux-nfs@vger.kernel.org,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna@kernel.org>, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH] nfs: reduce stack usage of nfs_get_root
Date:   Wed, 27 Sep 2023 09:45:25 -0400
Message-ID: <BAF96CD3-98A1-4D61-B188-BBCFBE81EA22@redhat.com>
In-Reply-To: <20230927001624.750031-1-npiggin@gmail.com>
References: <20230927001624.750031-1-npiggin@gmail.com>
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On 26 Sep 2023, at 20:16, Nicholas Piggin wrote:

> Move fsinfo allocation off stack, reducing stack overhead of
> nfs_get_root from 304 to 192 bytes.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> Hi,
>
> This is motivated by a stack overflow described here:
> https://lore.kernel.org/netdev/20230927001308.749910-1-npiggin@gmail.com/
>
> NFS is not really a major culprit but it seems not too hard to
> shrink the stack a little.
>
> Thanks,
> Nick

Looks good, might be able to get rid of the local "root" var too if the
compiler doesn't optimize it away.

Reviewed-by: Benjamin Coddington <bcodding@redhat.com>

Ben