From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-170.mta1.migadu.com (out-170.mta1.migadu.com [95.215.58.170]) (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 14D502DCBE7 for ; Fri, 23 May 2025 03:57:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747972631; cv=none; b=GbM8SFewL1WrDgZgMzCd7uYY3c1P9YL1qCPOsUsXop+c18lPI75dB5GS3SMpOSvmHFmbxi1Z5urlLOkSTP4myPj/eov+4iE7HZW0QJShZP1mAcZD4IW/5prOe+gFRvs+ay9BSZOtgpqqR/uQok0z3RXlgX8xhz77zkwx+gv/xZs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747972631; c=relaxed/simple; bh=1wmftH4+1CyP4uZ75vOAyuBVMc6P1BmvNKUb+IESNQc=; h=Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Message-Id:References:To; b=nwG2iuJ6HnaeUWhRsHpxd502XuQcz8/NTJcF7gZDSEuayvMr4glwgztD0DrOTIXwaSw302bDxXLHYWOIQdHs3SlYPyQfap8GJWp2FgUnbtPFhypNKZt1d9DyTo3Z61Kn4Gly6wOgnv1Nkob0x/57wtpqHnnmfENzjQhGxFoDmeY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=S9OzoP15; arc=none smtp.client-ip=95.215.58.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="S9OzoP15" Content-Type: text/plain; charset=utf-8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1747972614; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=u6qNdPv7J8gfgypOptH2B2wxSfGN00CcXcZhVQxMpKw=; b=S9OzoP15OwVpDAPDuHOpq6gcuxnTztYLM95nwFD4B9AK0NZwuCkeMbRE0EBh8cROyAudfN T88Cj2bQRKe0iodB9Lo34vZXtKv8Zoa2alqS/LtQ+5NS4kLuvg4xwkpuyC996wzkPdrQ1s DL+c8yhMEtO6U1+kbnDaI1lCJxj1EMM= Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3826.500.181.1.5\)) Subject: Re: [PATCH] mm/hugetlb: fix kernel NULL pointer dereference when replacing free hugetlb folios X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Muchun Song In-Reply-To: <4e408146-7c77-4f6d-90e8-bb311d7ab53d@126.com> Date: Fri, 23 May 2025 11:56:11 +0800 Cc: Oscar Salvador , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, 21cnbao@gmail.com, david@redhat.com, baolin.wang@linux.alibaba.com, liuzixing@hygon.cn Content-Transfer-Encoding: quoted-printable Message-Id: <299A777D-DC94-4724-BAD7-DD02F7CDBAFA@linux.dev> References: <1747884137-26685-1-git-send-email-yangge1116@126.com> <644FF836-9DC7-42B4-BACE-C433E637B885@linux.dev> <3B8641A1-5345-44A5-B610-9BCBC980493D@linux.dev> <4e408146-7c77-4f6d-90e8-bb311d7ab53d@126.com> To: Ge Yang X-Migadu-Flow: FLOW_OUT > On May 23, 2025, at 11:46, Ge Yang wrote: >=20 >=20 >=20 > =E5=9C=A8 2025/5/23 11:27, Muchun Song =E5=86=99=E9=81=93: >>> On May 23, 2025, at 03:32, Oscar Salvador wrote: >>>=20 >>> On Thu, May 22, 2025 at 08:39:39PM +0800, Muchun Song wrote: >>>> But I think we could use "folio_order() > MAX_PAGE_ORDER" to = replace the check >>>> of hstate_is_gigantic(), right? Then ee could remove the first = parameter of hstate >>>> from alloc_and_dissolve_hugetlb_folio() and obtain hstate in it. >>>=20 >>> Yes, I think we can do that. >>> So something like the following (compily-tested only) maybe? >>>=20 >>> =46rom d7199339e905f83b54d22849e8f21f631916ce94 Mon Sep 17 00:00:00 = 2001 >>> From: Oscar Salvador >>> Date: Thu, 22 May 2025 19:51:04 +0200 >>> Subject: [PATCH] TMP >>>=20 >>> --- >>> mm/hugetlb.c | 38 +++++++++----------------------------- >>> 1 file changed, 9 insertions(+), 29 deletions(-) >> Pretty simple. The code LGTM. >> Thanks. >=20 > Thanks. >=20 > The implementation of alloc_and_dissolve_hugetlb_folio differs between = kernel 6.6 and kernel 6.15. To facilitate backporting, I'm planning to = submit another patch based on Oscar Salvador's suggestion. A separate improving patch LGTM. >=20