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 B5FEAEACD for ; Thu, 12 Feb 2026 11:41:23 +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=1770896483; cv=none; b=IySY7t63agJaJSOajMOP749tifaK9FL41Uy9xnZLrlhzs9UYCmL2WuxIrY46YW1DCviOw8+nk/xJyH5kmjF8L0WzqNCcOMHPrOZrnicqQf2XX/ZOFngt8Z5UMvEmDX8pwvUEvrHeNOzFMkSLcIJj9F+S4BjzaOowvKl9lfJNalU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770896483; c=relaxed/simple; bh=ZH+HbmVIIzMcIEa9LGN6wkR8qjpnh0O5mXXLZ+jp/ak=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ST/3SNma0fS8rWFZNlO4E9Zh9FWB91fwuqRWScu8DwU9m5mAGx+BObFpUdRCNcYtXDGNgoD2AMifHTW/8ZBnq8hcuDmZRZixJHjugD/sz3inqRGLVvGATmvaIe2h48QgyTm7TWXTZ3yeLjWNm/hO04f3eH9cOb5Opk7IMDSWOHU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZRwvhRXh; 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="ZRwvhRXh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52C7AC16AAE; Thu, 12 Feb 2026 11:41:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770896483; bh=ZH+HbmVIIzMcIEa9LGN6wkR8qjpnh0O5mXXLZ+jp/ak=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZRwvhRXhOyGP3akEut1HqTFpeodKL4dVxRPzvaQknwLED6HfcBS/051ZarH20JOZ3 enUK0HUxeog6dcdFzX6w9NeBTgKb69cst6G1M4cmliddugqq9a3bfjTB8jHrp+53pH 3KqJK/uJgPyOUsjRm47AYQgpJhH4HW1u2rkNTLARSwLv9l8YBaLC2cLrKkTETszu1+ xB+moFk/aQrxBvZ4ti4W3TmizA5rUqf+GpXLtnw+u90WdnPDwBJzbd3yU2A3Z55GbN U091G3xG/XyFhlDnHRtsjGr9J81Bkmo1TPjGDo6u/lmh2RNQADUT36vV+5bV5U7sqO flsTA3feP8fUg== Date: Thu, 12 Feb 2026 13:41:16 +0200 From: Mike Rapoport To: Michal Clapinski Cc: Evangelos Petrongonas , Pasha Tatashin , Pratyush Yadav , Alexander Graf , kexec@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Subject: Re: [PATCH v3] kho: add support for deferred struct page init Message-ID: References: <20260211173954.2091119-1-mclapinski@google.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260211173954.2091119-1-mclapinski@google.com> Hi Michal, On Wed, Feb 11, 2026 at 06:39:54PM +0100, Michal Clapinski wrote: > From: Evangelos Petrongonas > > When CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, struct page > initialization is deferred to parallel kthreads that run later > in the boot process. > > During KHO restoration, deserialize_bitmap() writes metadata for > each preserved memory region. However, if the struct page has not been > initialized, this write targets uninitialized memory, potentially > leading to errors like: > BUG: unable to handle page fault for address: ... > > Fix this by introducing kho_get_preserved_page(), which ensures > all struct pages in a preserved region are initialized by calling > init_deferred_page() which is a no-op when deferred init is disabled > or when the struct page is already initialized. > > Signed-off-by: Evangelos Petrongonas > Signed-off-by: Michal Clapinski > Reviewed-by: Pratyush Yadav (Google) As Pasha mentioned, please add Co-developed-by. Reviewed-by: Mike Rapoport (Microsoft) -- Sincerely yours, Mike.