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 19BB51531C1; Tue, 30 Sep 2025 00:49:09 +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=1759193350; cv=none; b=op4rmyRb6DvBNeuCPeyQotMnhlCWqZ7rjAV2ezN5THEW0Hpn+colCF6XFx1WnQxt6lJAqNPvcLQNsW4cULgQn/1o64W9Roo8lznINeyu+uO2E+zW8MUOyihEjGQg78e+gVNgwdPK8RqyA2PvLHDOQT88d9c+ggGK1C9cxcFATWE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759193350; c=relaxed/simple; bh=Dmx25bmLQf6ATWT8g8tetZDOFF0vBbRp6vW8hTDcyvc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XN5LGpUaDG9y3SWDd63aGRDenr+/KM7FaeGyiOeo5tsBK7O4q9fLEFLoyuyt99SwzY7LAj6+WgsEMncNMzsf2TmArxO+HcOmnHJ5Gqh6tC6JPEcrQmpKxqoBycqcf/3WpdqvJ+gfq8+/SZ7+RJx5BbZEGFv20+1WiK/zNka76V8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QhK76q+a; 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="QhK76q+a" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6388CC4CEF4; Tue, 30 Sep 2025 00:49:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1759193349; bh=Dmx25bmLQf6ATWT8g8tetZDOFF0vBbRp6vW8hTDcyvc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QhK76q+aJngACoGRYQpbuwf9uBLxE7n+FfDFAI6Bz7CRfp9ohr/mdN6MzNy4Y+cbF PJP3xHR20cu+BzyuUy7Gl3Qq82r3fg7EjaQpikJUEUz5+5xCPugK97xs6t9FDM0xyY Hd+vzUifNrzATwg4X9wlRNkTkZm/oMoYzEk7KqYkK9Y6hICU0FW4U7iL6UfuxGRsHK wdZSrpIjBc+gy+9jQDWi0BHwdvjG4pGW4CoT5SkisCEv+htE+KSj5g3N+hDZapdrKc /pSALxpvqkak+zEX88oxB+WXrJ9oaDh9IV3eztg7ZJzgtaHheTeX3az3YS6ksRPxUh ZV/EXsYxjXcrw== From: SeongJae Park To: Xinyu Zheng Cc: SeongJae Park , Andrew Morton , "Paul E . McKenney" , Peter Zijlstra , damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, zouyipeng@huawei.com, Hugh Dickins Subject: Re: [BUG REPORT] mm/damon: softlockup when kdamond walk page with cpu hotplug Date: Mon, 29 Sep 2025 17:49:07 -0700 Message-Id: <20250930004907.55388-1-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Thu, 25 Sep 2025 19:11:13 +0800 Xinyu Zheng wrote: > > > On 9/20/2025 6:42 PM, SeongJae Park wrote: > > On Fri, 19 Sep 2025 20:56:56 -0700 (PDT) Hugh Dickins wrote: > > > >> On Thu, 18 Sep 2025, SeongJae Park wrote: > >> > >>> Hello, > >>> > >>> On Thu, 18 Sep 2025 03:00:29 +0000 Xinyu Zheng wrote: > >>> > >>>> A softlockup issue was found with stress test: [...] > > Xinyu, could you please test if the below attached patch fixes your issue and > > let us know the result? > > > > If Xinyu confirms the validity of the fix and no one objects to the above plan, > > I will post the fix as a formal one with a better commit message. > > > > Hi, SJ. The below attached patch is works! > > These days, I reproduced the same softlockup scenario for three times. > It can be reproduced around an hour when I increase the memory pressure. > Then I patched the below fix, and ran the same testcase whole day, > softlock didn't trigger again. > > Sorry for the long wait. Thanks again for your solution and explanation! Sorry for late response, and thank you for confirming that the fix works. I just posted it as a formal patch: https://lore.kernel.org/20250930004410.55228-1-sj@kernel.org Thanks, SJ [...]