From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 505DE3F86FB for ; Fri, 29 May 2026 15:25:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780068335; cv=none; b=UOAm+7sTWiHww7AbmPndeTmH0Co6bf5XmmZpXMWdzpZpbduXt0Ir7BTMYzFI/4R6BIS8dCMq6T+zShg/twITzzF7NTs9ZhVA9o1PHYwCfoUDwu3lec/hepSEPmaXKkCewX20pSvHD48nWgEXQWQf92v4O5mAlQBEKNWNo40PZ9o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780068335; c=relaxed/simple; bh=Z+HYjvvqCchjYSSoU6qbOk9Gov2pfNet7tVjjUNszJc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kjzdQ0aDtNUiqsquwVp2nJqihZMmYqxSTfCyFqpoQFTc56r+5qthpA2foOsSbdb6/Y3+/wCpmkOQrJgGFMtd+pOMS0QRbRnxg6TtJ74J26pffJPL+tTgIfER8aBeKXfmUlatjNVUkBSW3F1ycycc+1TYswuUzdEv1dXA/pLPlNI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=BmMhnZBc; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=ekUhgd8j; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="BmMhnZBc"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="ekUhgd8j" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1780068333; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=PJ5vvVKjiUlKZvlIAO4D+aYwhndM/ly8HIEHblxR0ik=; b=BmMhnZBcbnZeooEGRJWEDpBFjKaMXv7WG4JWRasxcUPOAk18QDsLlWe6R2tUeIAG9UoCsw ZtaCNLgeCjYYOy9Px8hqoxQxR6g2xmzlydPcbeaSb0lddtVB+XeAgW8KxsmbSmJvYGaHln I4xMjB/ocJif38B9oTDJ9foErIGrHX4= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-325-26sApI2SOPq9i24u0GhraQ-1; Fri, 29 May 2026 11:25:31 -0400 X-MC-Unique: 26sApI2SOPq9i24u0GhraQ-1 X-Mimecast-MFC-AGG-ID: 26sApI2SOPq9i24u0GhraQ_1780068331 Received: by mail-wm1-f69.google.com with SMTP id 5b1f17b1804b1-48d127eb013so67712875e9.1 for ; Fri, 29 May 2026 08:25:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1780068331; x=1780673131; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=PJ5vvVKjiUlKZvlIAO4D+aYwhndM/ly8HIEHblxR0ik=; b=ekUhgd8jLS5PtptZrkDO5CNctLYHpWZ21mWlFJ/CSEFXSbjyLI77B6iAMi0776MSEv KKM2iFvBkayVpkgvLCtc5Ns7MDXBg3P12WkWZo7n9B91HRpWlHC/YVgsXwknrXKNdQ6C eKvvmPzWWhEmu1/anP5/0taJp4zNHSYso4PkUwz8gXQnkGH0k+6EOVvlIYs0H8Ru88c8 veZVZ00h6o6Sk3SfpaarYGsF3E1rbtNAc3sB/bfXx7WG4yVBgoSUFXyHkx1zzcZtfZ+P XOWJClrJTjVk3nFDsX+M4bHOmeC5PUZ0NGxkmOiJNrnOfx2kyWt1ZsNCJ5B3EaQhddvk W1Cg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780068331; x=1780673131; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=PJ5vvVKjiUlKZvlIAO4D+aYwhndM/ly8HIEHblxR0ik=; b=g9452kHG9NcbK96PTiUjcsTAKb+7g6PDGih/IeSz3cDe0y65Mv00Iq4mP0q+zadGkB ycC1wC/gjITq24zSv8Z7y4HN4TkmsIfOWsncs30D96NVhH6ltpQwxsg7s/ra2NcOJeTN F9+GsImdmFbJZiQyEAKaUIL705UKKvJPOyOM5wMdM2eVzqzJ0AwgRIs3v8J7yo0IBKk+ wF6G0ubmug00el8MvhELuvwZ1ntNuLfWc6QRRtHqVHbKogtZ/DdDGMBLmnbY2BL/dY5g GZbutswJxYah7WFBjyniFE+amOIjAVzJSmFumSjpb0UFmWivsBGLPZdVS/awV+SzpjC7 W32Q== X-Gm-Message-State: AOJu0YxvOseXKQYcTC/ZZVusmbRTeB/b+337cOa6yQEZwrKheJXr0t3w YpG4vpduLvcuTHvz9IORZSCyI9KAjE9kOM8ncnmqXte5WWFOERHn8Pn7IfEn61Njvf1wkOGFW0J CFD/sC51zEAjHQesbrmTpzFcV94MXeiI8vQDqykQ0GWyT0+fl+TZSdGg03x4w3RivsvHT8XWcoW mEdsNjpmyV1UUxqJP7vWH1Z8WT0yvKrf9AWIMn0x+wOmM= X-Gm-Gg: Acq92OHRIxnaa2rjJphibTLNGk+QdN6TmN5jpdk+/ClTy6+eDlhx1Q9pcQkA/Fo/mSn MjX3uKWsbM/WHkAraHSOWNFGIFY+FWpjCQXtKbBly9N1CKyxijkMeIERaoyw/jrsN7ANJa5tMsk j9nmoKW87h2MHUqAgP5INGdj6NRVuXJjW470WO0gFyRP9r/tU54bD1i1rrUaWsHn63EdUHax6yL ZLTOAGP7eN/P7Oak7ue4nut7L+t9nmxCT3DwpxJpH8KbLHWoXJWjruVA9Pz6wQOreMEfFDbRV2D OjBqvsUnkZZVyU3b1AdViqHBMfTIwAu/OsTrZiqLt4dU6yDqm2ZFbtzlnvoGb3AoDxJo3WQCIJG MbL8zncdAMUVPjwOZQs/Y8aX1c6bDWTB3kttWNk+NbaQkPOiLWT7UyA== X-Received: by 2002:a05:600c:4f89:b0:490:4717:970f with SMTP id 5b1f17b1804b1-490a292ec27mr1653895e9.14.1780068330495; Fri, 29 May 2026 08:25:30 -0700 (PDT) X-Received: by 2002:a05:600c:4f89:b0:490:4717:970f with SMTP id 5b1f17b1804b1-490a292ec27mr1652655e9.14.1780068329671; Fri, 29 May 2026 08:25:29 -0700 (PDT) Received: from redhat.com (IGLD-80-230-25-45.inter.net.il. [80.230.25.45]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4909d6a0a89sm62305115e9.7.2026.05.29.08.25.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 29 May 2026 08:25:29 -0700 (PDT) Date: Fri, 29 May 2026 11:25:24 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: "David Hildenbrand (Arm)" , Jason Wang , Xuan Zhuo , Eugenio =?utf-8?B?UMOpcmV6?= , Muchun Song , Oscar Salvador , Andrew Morton , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Hugh Dickins , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , virtualization@lists.linux.dev, linux-mm@kvack.org, Andrea Arcangeli Subject: [PATCH v9 36/37] mm: balloon: use put_page_zeroed for zeroed balloon pages Message-ID: References: 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: X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent When a balloon page marked PageZeroed is freed during migration, use put_page_zeroed() to propagate the zeroed hint to the buddy allocator. Previously the hint was silently lost via plain put_page(). No page has PageZeroed set yet; the next patch (VIRTIO_BALLOON_F_DEVICE_INIT_ON_INFLATE) will set it on pages the host has zeroed during inflate. Signed-off-by: Michael S. Tsirkin Assisted-by: Claude:claude-opus-4-6 --- mm/balloon.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/mm/balloon.c b/mm/balloon.c index 96a8f1e20bc6..6c9dd8ab0c5d 100644 --- a/mm/balloon.c +++ b/mm/balloon.c @@ -324,7 +324,15 @@ static int balloon_page_migrate(struct page *newpage, struct page *page, balloon_page_finalize(page); spin_unlock_irqrestore(&balloon_pages_lock, flags); - put_page(page); + if (PageZeroed(page)) { + /* Atomic to serialize with memory_failure's + * TestSetPageHWPoison; not under zone->lock here. + */ + ClearPageZeroed(page); + put_page_zeroed(page); + } else { + put_page(page); + } return 0; } -- MST