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Date: Mon, 22 Sep 2025 16:08:36 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: "yanjun.zhu" <yanjun.zhu@linux.dev>
Cc: Mike Rapoport <rppt@kernel.org>, Alexander Graf <graf@amazon.com>,
 Baoquan He <bhe@redhat.com>, Changyuan Lyu <changyuanl@google.com>, Chris
 Li <chrisl@kernel.org>, Jason Gunthorpe <jgg@nvidia.com>, Pasha Tatashin
 <pasha.tatashin@soleen.com>, Pratyush Yadav <pratyush@kernel.org>,
 kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 3/4] kho: add support for preserving vmalloc
 allocations
Message-Id: <20250922160836.8d0dc984ff0986b3809c9ab0@linux-foundation.org>
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References: <20250921054458.4043761-1-rppt@kernel.org>
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On Mon, 22 Sep 2025 15:31:42 -0700 "yanjun.zhu" <yanjun.zhu@linux.dev> wrote:

> > +int kho_preserve_vmalloc(void *ptr, struct kho_vmalloc *preservation)
> > +{
> > +	struct kho_vmalloc_chunk *chunk;
> > +	struct vm_struct *vm = find_vm_area(ptr);
> > +	unsigned int order, flags, nr_contig_pages;
> > +	unsigned int idx = 0;
> > +	int err;
> 
> This is a trivial issue. I’m not sure whether RCT (Reverse Christmas 
> Trees) is used in the Linux MM mailing list.

Not as far as I know.  Some like it.

If I was to have a preference I'd suggest that things be laid out in a
logical order rather than by column count.  Group like things together,
avoid use of unintialized storage in initializers(!).