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Date: Wed, 24 Jun 2026 13:50:02 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>, Amir Goldstein <amir73il@gmail.com>,
 Alexander Viro <viro@zeniv.linux.org.uk>, Christian Brauner
 <brauner@kernel.org>, Jan Kara <jack@suse.cz>, "Matthew Wilcox (Oracle)"
 <willy@infradead.org>, Nhat Pham <nphamcs@gmail.com>, Johannes Weiner
 <hannes@cmpxchg.org>, Shuah Khan <shuah@kernel.org>,
 linux-unionfs@vger.kernel.org, linux-kernel@vger.kernel.org,
 linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
 linux-kselftest@vger.kernel.org
Subject: Re: [PATCH 0/3] ovl: make cachestat() work
Message-Id: <20260624135002.09ab1f9387eb4708b0707175@linux-foundation.org>
In-Reply-To: <20260623111533.2285005-1-ptikhomirov@virtuozzo.com>
References: <20260623111533.2285005-1-ptikhomirov@virtuozzo.com>
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On Tue, 23 Jun 2026 13:14:47 +0200 Pavel Tikhomirov <ptikhomirov@virtuozzo.com> wrote:

> We were using cachestat() for our internal Virtuozzo cache related tests
> and I saw that test behaves wrong on overlayfs, syscall returns all
> zeroes instead of any meaningful cache statistics there. Let's fix it
> similar to what was done for fadvise().

Thanks.  Sashiko seems to have a found a couple of issues:
	https://sashiko.dev/#/patchset/20260623111533.2285005-1-ptikhomirov@virtuozzo.com