From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 94DE22D3ECF; Mon, 29 Jun 2026 14:55:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782744945; cv=none; b=L6p2EsjPijo0c7yhLAq27xdHfL9S/VM17TIyxpCTVn6ZhS6bR/OvcBQPk3pPXQN8IgOdx2/NSstdILX6BRoeyMp5iTtBcsWkr/r1JF1HRiIwLyQXupzzNJrWrBxuNfuDMuIS2YPmzB7LHdoCcr+XT9ZYliO/yc/pfbv7GlmXGGQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782744945; c=relaxed/simple; bh=Mql/l83FECvFqg0Gh57RZqJvWvCvaXofOvjdJf4tikE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EJHO2+bH3XOMRJiovgycseuS6nSZjyPmG4R4uyC7gEbn3+Z8jQEfftsjtghMXFv3r2v00srtD+7TPB3Ddmhvzlb5krr1NSZL5wkHaeadm0G+FtrnL+yrxNGiAXXcs7vAQV9GTXuv149R1H+LYqOHnS1Dga76lN5bQLasVxen2YE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f+GrKNZl; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f+GrKNZl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC58C1F000E9; Mon, 29 Jun 2026 14:55:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782744944; bh=pL/OIFxAfmJMENrJselHOaTQtQ71A4Uv2SXDoGfSIdk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=f+GrKNZl7rNDdeHLjnA2IB+t3bNGbNvt5GRbLNylwd+JKc+cKoP7w8Fz4BYL4Rqqr gFT6c0KH0T1AalBrpEGas5knLBzNAM3qvYqjZgmVuUOlBw+q9989VvK6+yPzWb2UyW e0QOaZ+MVQJzwy1ggUIhkmRczkXuvnc7fh8IPD9if0B3NKooMt8jss/76jTUfviBmy /aoSOQH24JiPeacnNEtiIjHbY0GUe4qWT/w7Q318mehq/RvzxycjrT4l+0+hXqwr8i 6Z611YYQ+KzizEl3blr1WDy8CDzWgtqALDZj2RvKi44PiqoDTMlN4NBVQwzv99uzb2 pfz8FLfsvZcNg== From: SJ Park To: Andrew Morton Cc: Akinobu Mita , SJ Park , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, SJ Park Subject: [PATCH 1/5] mm/damon/core: use kvmalloc for target regions array Date: Mon, 29 Jun 2026 07:55:32 -0700 Message-ID: <20260629145538.134832-2-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260629145538.134832-1-sj@kernel.org> References: <20260629145538.134832-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Akinobu Mita damon_commit_target_regions() temporarily allocates a single contiguous memory region using kmalloc to store copies of all damon_regions of the damon_target. However, if the damon_target has a large number of damon_regions, the total size may exceed KMALLOC_MAX_SIZE. This problem can be avoided by using kvmalloc instead of kmalloc. Signed-off-by: Akinobu Mita Reviewed-by: SJ Park Signed-off-by: SJ Park --- Changes from v1 - v1: https://lore.kernel.org/20260603112306.58490-1-akinobu.mita@gmail.com - Collect R-b: from SJ. - Rebase to latest mm-new. mm/damon/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/damon/core.c b/mm/damon/core.c index 3dd2750c2ef20..ded76719e8a14 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1362,14 +1362,14 @@ static int damon_commit_target_regions(struct damon_target *dst, if (!i) return 0; - ranges = kmalloc_objs(*ranges, i, GFP_KERNEL | __GFP_NOWARN); + ranges = kvmalloc_objs(*ranges, i, GFP_KERNEL | __GFP_NOWARN); if (!ranges) return -ENOMEM; i = 0; damon_for_each_region(src_region, src) ranges[i++] = src_region->ar; err = damon_set_regions(dst, ranges, i, src_min_region_sz); - kfree(ranges); + kvfree(ranges); return err; } -- 2.47.3