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 E9399305675 for ; Sun, 17 May 2026 20:06:51 +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=1779048412; cv=none; b=M4yFc9IRcTQMC78Rq9LQkRXXaZZa3OmWp/uI5FQapqO02kuCBK9aZv8MEC0mF6yV44Ou/rCLCSrz9tr4NBu33NofMhf1/laA/WgMLMz2PB3aJWz86lXRPEhhQ0g21k9/Ztf/9MIIm6EeGs2jgqCbMN8TRcBDguFOyxYYNdC77Yg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779048412; c=relaxed/simple; bh=1jR4VX0JH89Q5myxphrlJ1We7QqP2GmhqIm9qlScids=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pCJJrg1iREiD0yTtO9hpMdJ/xHWWhOr49DN90txTWvcv5JxUsZdptHO8DBFnLs5ssx8MRB/V7Kwq0znmx8D9nAORkmspCQgcfpdsGUjGepsCykzxXxOcBgX4nQThcWXCTZEuBtysqEFBX48f1PaEujVAiDh0IYjuwoz9dY3BcYo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kLsN1KPy; 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="kLsN1KPy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D5B7AC2BCB0; Sun, 17 May 2026 20:06:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779048411; bh=1jR4VX0JH89Q5myxphrlJ1We7QqP2GmhqIm9qlScids=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kLsN1KPyLk8DdyXryMn4yzh4aQAsjdgC+8dX7efJ36TBpLZMTeTyVl3hR5NMxjRuo Qpo2CDWraGCLYVgHP+39Jvhi8QNHNXTWk9Q4lhwD0ohmDKHBzvJ4GxBkjd+5WSlU+K uys/Y1AoA7KX9GAn319kuuxkVY7OSFN2aL7IgiWw6jvVltdGHFoe3mHyJAQdP9LgBK 08/QGZ3jQUARoKrxskI4eWS8lNC4hyvmRA/ui8UtxqUAsMK8Mf/w/BRrt6QjpeqJrG LCQ5RV8vP26luMXvup77gPJaCgZdK4nWzkYdH0ZM6IlmrH1558CBFnJKrzIO9mIhyD NtQjGd7QibKZg== Date: Sun, 17 May 2026 22:06:43 +0200 From: "Oscar Salvador (SUSE)" To: Georgi Djakov Cc: akpm@linux-foundation.org, david@kernel.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org, osalvador@suse.de, gregkh@linuxfoundation.org, rafael@kernel.org, djakov@kernel.org Subject: Re: [PATCH v2] drivers/base/memory: set mem->altmap after successful device registration Message-ID: References: <20260514092657.3057141-1-georgi.djakov@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260514092657.3057141-1-georgi.djakov@oss.qualcomm.com> On Thu, May 14, 2026 at 02:26:57AM -0700, Georgi Djakov wrote: > If __add_memory_block() fails at xa_store() (under memory pressure > for example), device_unregister() is called, which eventually > triggers memory_block_release() with mem->altmap still set, causing > a WARN_ON(mem->altmap). This was triggered by modifying virtio-mem > driver. > > Fix this by delaying the assignment of mem->altmap until after > __add_memory_block() has succeeded. > > Fixes: 1a8c64e11043 ("mm/memory_hotplug: embed vmem_altmap details in memory block") > Signed-off-by: Georgi Djakov Acked-by: Oscar Salvador (SUSE) -- Oscar Salvador SUSE Labs