From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793304997; b=mCTbHNVc8eBwgIzhq+hQ9J2WuxWTJyHIT4wbb8nl9OfpHWMa7AladL85B6Hjq5xjXpJ0 99vtuF+cTgbPWZdcFe9V4ZWIWb7rECS/5xs2HGa0w2VkQpnE84dplM2PfE/wGj5w6+Q3W 4CuCxeIA2xVDamOBWWpiU2kIF58Wn451RwgSJMFvfJB8FJOO9W1uS7LO8qL/BA7UTFR9g f2lqOWDtUuyvLmi0vTsgS8IofFQPRZT8V74AutBzpeRo+cSHMS/qi8jslCJDaTuY4WAal 85C+HMXjGT4qAfZg7fb+LQSQnfQ4JHY0lVC2O0ns4GHnWz0iKe8DgspAaChKkA3qr7w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793304997; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=2ZgkjScb+0OD9v26VHxT1ff4wS3soVAyGNbtaNaBaFU=; b=g+FkjAdPhmFegsX8E9Wrfgsomb6M3FZxUkWkPRiExZd1djRaNlhYW6PDdiVCCFAOMMbM Q0CSjuiz/vmsMean31rkdSgGdzJS5FV6ckMzTxazQT8uLrQ/Jieqy1Kti5kypDJM2uwij ZT4sCOcIPY+pBZAstf7HTL+muQrKKbqAMSYob7ljMW9q+39U2tzSofiAqMkhw5wyB03vs 6Jha4NrBTlPa0pU9YaTXKhWV0SAltoPfIWvdYEABcCFbUT8ixHO5Rvj/QSUILcVaR4doH K/y6Gvfhqg5pjIXhQHjeGJ7kQr+Kbf0G+H1t5GwrIu4uD14f/K1rpy/iRa2yRYh9pKw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="EOocZ/x2"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 100C7606A31C for ; Thu, 29 Oct 2026 20:16:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=EOocZ/x2 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99C9E1F01816; Thu, 29 Oct 2026 20:16:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793304996; bh=2ZgkjScb+0OD9v26VHxT1ff4wS3soVAyGNbtaNaBaFU=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=EOocZ/x2foPyhub1OxrymFy/dVAcS1XnJONRSADh8daKeX9xDUgfMHryHN9Ul3YhS PpeyGM/mRBNt8+rj9td8QnMxA0BWzWrsjx9IlS5+SN20FxFEh4qjiEmNRSaQT6SXAi LZz6nmK6n8rZmWlIuh6p1twy/lEuaC2Pa9JLtiElG+ycTmQyYrQ+6Qij/rSC2Gt6U4 DQPMap/OhhSKJLQ4NPt+P3f6GTzqV4mzNyrILjKy32CWPUt0GB5AX4TNPZb9a+gt9V CEi35SepJZq/BIKaoSlRLTQRCOfiF22klw7LCvXZpHnwC3LGoXqPwCXwdFENhVKtcY 99wsdxSrVbFBQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 13/15] mm/hugetlb: fix reservation leak on min_size= mounts Reply-To: sashiko-reviews@lists.linux.dev To: =?utf-8?b?RGF2aWQgSGlsZGVuYnJhbmQgKEFybSk=?= Cc: linux-s390@vger.kernel.org, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" In-Reply-To: <20261028-fixes_hugetlb-v1-13-a0a033db180f@kernel.org> References: <20261028-fixes_hugetlb-v1-0-a0a033db180f@kernel.org> <20261028-fixes_hugetlb-v1-13-a0a033db180f@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 29 Oct 2026 20:16:36 +0000 X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Chris Mason >=20 > Failed allocations for CoW mappings can leak reservations on hugetlbfs > mounts with min_size=3D and no size=3D. The leaked reservations survive > unmount. >=20 > HPG_restore_reserve makes free_huge_folio() restore the global > reservation without returning it to the subpool. This assumes the > reserve map holds the reservation. However, a CoW mapping may have no > reserve map, or the map may already account for another folio at the > same index. >=20 > Commit 58db7c5fbe7d ("mm/hugetlb: fix avoid_reserve to allow taking > folio from subpool") allowed owner CoW allocations to consume subpool > reservations. Commit 51e1de00acdb ("mm/hugetlb: simplify > [ ... ] > Fixes: 58db7c5fbe7d ("mm/hugetlb: fix avoid_reserve to allow taking folio= from subpool") > Cc: stable@vger.kernel.org > Signed-off-by: Chris Mason > [ david: simplify comments and improve description; updated Fixes ] > Signed-off-by: David Hildenbrand (Arm) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261028-fixes_huge= tlb-v1-0-a0a033db180f@kernel.org?part=3D13