From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C607D37473A for ; Mon, 30 Mar 2026 23:34:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774913675; cv=none; b=h3jgujefiJ9ukXuL0caCEr4rfse0PygbREF5G9L6ZCh/vuG9PDOwhG9hL4E8F+q961UZ8bxgWNCwwL6lldtFJwkHaDRoIBQ7+PKg7yQsA6Td5ZMYLmYfJNr5vA+W6qk/m27wPj/BkLm4uxiOCg5w0l8GdD4wHTcM7qNLOxTVNy4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774913675; c=relaxed/simple; bh=rOYFqfKdOMzs6VYlE42XKH2BfXEceu73iEUs4F1Vap0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MQM2iCHOP/zDFXJgdGSqC1h64omdQF1H31DWRRZ3xUnAbYEQ6GVJLi+H6O1veALOhkficKn7q6vnwdr3oke3Qvwk/OIpf1WOOCELKBegbcr8yTJy9G7quDOUyU4ZZUrIVX7pGb4+NTBd1xjJOtZhJD41AOy5BfxnyZEu4QymHmg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Q0YAvTKn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Q0YAvTKn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 369FEC4CEF7; Mon, 30 Mar 2026 23:34:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774913675; bh=rOYFqfKdOMzs6VYlE42XKH2BfXEceu73iEUs4F1Vap0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q0YAvTKn5WBKHz+KwKESwmbAcutQnWmbccH7rgz8A7WonyeJY8YyPbzAxOillO9MM GtSxTB0Hhz7wBI4JlJeRRtfZC2+s7iYAOVHDjEnQ4/uGBgsSStN/j8bWOp21nuVbcB kI9s8v2SACens+zjjLcpbmyceHmN4P7x7mhYUTFEew7Q3lKZiufCX+DB4cD0gz4Qxq 3I4WTnasME00xo6bp1jckmsp1JdqwdrjU2292mVvkan5V/rdHAGfqF0QLr/dj3Atfy bh7+MUyAZufkS068bcOXTmbe2PzBIP55XIPWttUDUAkmOYTgYB1iE3DXVZNxpqcOy9 9m32l7Ru/oEPA== From: SeongJae Park To: Liew Rui Yan Cc: SeongJae Park , damon@lists.linux.dev, linux-mm@kvack.org Subject: Re: [PATCH] mm/damon: validate addr_unit to be power of 2 Date: Mon, 30 Mar 2026 16:34:33 -0700 Message-ID: <20260330233433.4208-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260330071736.17143-1-aethernet65535@gmail.com> References: Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Mon, 30 Mar 2026 15:17:36 +0800 Liew Rui Yan wrote: > On Mon, 30 Mar 2026 14:08:51 +0800 Liew Rui Yan wrote: > > [...] > > > > min_region_sz = max(PAGE_SIZE / input_addr_unit, 1); > > if (!is_power_of_2(min_region_sz)) > > return -EINVAL; > > Apologies, I just realized I made a silly typo in the code above. No worry. > > I used PAGE_SIZE where I should have used DAMON_MIN_REGION_SZ. While > they happen to share the same value in many cases, DAMON_MIN_REGION_SZ > is the correct semantic constant for this context. > > The code should be: > min_region_sz = max(DAMON_MIN_REGION_SZ / addr_unit, 1); Yes, I agree. > > Sorry for the confusion. Again, no worry! Thanks, SJ [...]