From nobody Mon May 25 03:55:49 2026 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.3]) (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 046693F8EA7 for ; Tue, 19 May 2026 08:58:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.3 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779181132; cv=none; b=Y7Rb5r0u/iuq5bYPz1oXiQZYDxvMKCOz5OGER7aJYLMUbDdwpiw6+u5qYkXvvhDLADSJMhwuT1QooSxMIJsIZ0bzdfpCDuYDlxWU7XXAniyn4acT5FyVZ0J6JGr1MYRr9OtHZdUDkFTghMuPROSMMX+sAR7zUHv7hgpL0QMBUwg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779181132; c=relaxed/simple; bh=Jxg75yhmdY4W9DnGQkBG0Y0p0suS1JHjVv/6zC7VImY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=YOKOuV3TQWoAJQ4/yJjMReoYj6eac+oQ9XPO+JcGUpf30A9OfaS1eNY0SRLq6vUh11XjSI1/LPgDeSTZqPoBpJFCvOQVYhdB7+bPKFZEyth+paTwimoh1802S8UbeVgJaZXXT2Q0eDNGFw61uuzE/6jDNAe7zidzUOZFNHP9UTk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=K+nRoIyg; arc=none smtp.client-ip=117.135.210.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="K+nRoIyg" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=4o ATOtiXmQ/yx39W5TsVQjZLt0wrqUXZg1OirMThksQ=; b=K+nRoIygEMBhZNEdIf xLKFHyZaFiHDQNtXhvm8d8ewhPBbN9k0sh3zCZyIoqP41TSIMRVxMg+vtpgrzgLI U2rrZLAA3fl+pyCmdIsp+1FMXU/dEX0MasoE9BSPPzU7vKgKveOf315ZjLuAf6EC C2qcKHVaSqRb78lATwyNOmPzE= Received: from neo-TianYi510Pro-15ICK.. (unknown []) by gzga-smtp-mtada-g1-4 (Coremail) with SMTP id _____wDnL6YbJgxqAaPICQ--.45653S2; Tue, 19 May 2026 16:58:05 +0800 (CST) From: liuqiangneo@163.com To: apopple@nvidia.com, jgg@ziepe.ca, leon@kernel.org, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Qiang Liu Subject: [PATCH v3] lib/test_hmm: Check alloc_page_vma() return value and handle OOM Date: Tue, 19 May 2026 16:58:00 +0800 Message-ID: <20260519085801.172247-1-liuqiangneo@163.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: _____wDnL6YbJgxqAaPICQ--.45653S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxArWxCr4Dur1kKFWrWF1UGFg_yoW5Gr1UpF 48JwnIkrW3Xr1aqr17J3Wv9w1Skw4fta9rCFnxury8ZrZ8Xry5t3srKF4Fvr13Aayxta1f ZF4rtr1UuFn8uaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zE2-e3UUUUU= X-CM-SenderInfo: 5olx1xxdqj0vrr6rljoofrz/xtbC-B4uj2oMJh4bYAAA3m Content-Type: text/plain; charset="utf-8" From: Qiang Liu Check alloc_page_vma() return status for page allocation failures, free allocated pages and return VM_FAULT_OOM on error. Handle return codes of dmirror_devmem_fault_alloc_and_copy(), call migrate_vma_finalize() to remove migration entries from migrate_vma_setup(). Signed-off-by: Qiang Liu --- v3: - Clear dst[i] to avoid migration in subsequent migrate_vma_pages/finalize(= ) calls - Handle return codes of dmirror_devmem_fault_alloc_and_copy() - call migrate_vma_finalize() to remove migration entries from migrate_vma_= setup(). v2: - Add unlock and free allocated pages before return. - https://lore.kernel.org/all/20260514032345.32256-1-liuqiangneo@163.com/ --- lib/test_hmm.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 5430ef97bbe0..2d75a49e8e7f 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -1063,6 +1063,25 @@ static vm_fault_t dmirror_devmem_fault_alloc_and_cop= y(struct migrate_vma *args, /* Try with smaller pages if large allocation fails */ if (!dpage && order) { dpage =3D alloc_page_vma(GFP_HIGHUSER_MOVABLE, args->vma, addr); + if (!dpage) { + /* Unlock and free pages already allocated. */ + while (i > 0) { + struct page *fpage; + + fpage =3D migrate_pfn_to_page(dst[--i]); + unlock_page(fpage); + __free_page(fpage); + } + /* Clear remaining dst entries to avoid + * migrate_vma_pages/finalize() using + * uninitialized values. + */ + while (i < (1 << order)) { + dst[i] =3D 0; + i++; + } + return VM_FAULT_OOM; + } lock_page(dpage); dst[i] =3D migrate_pfn(page_to_pfn(dpage)); dst_page =3D pfn_to_page(page_to_pfn(dpage)); @@ -1148,7 +1167,11 @@ static int dmirror_migrate_to_system(struct dmirror = *dmirror, goto out; =20 pr_debug("Migrating from device mem to sys mem\n"); - dmirror_devmem_fault_alloc_and_copy(&args, dmirror); + ret =3D dmirror_devmem_fault_alloc_and_copy(&args, dmirror); + if (ret) { + migrate_vma_finalize(&args); + goto out; + } =20 migrate_vma_pages(&args); cmd->cpages +=3D dmirror_successful_migrated_pages(&args); @@ -1685,8 +1708,10 @@ static vm_fault_t dmirror_devmem_fault(struct vm_fau= lt *vmf) } =20 ret =3D dmirror_devmem_fault_alloc_and_copy(&args, dmirror); - if (ret) + if (ret) { + migrate_vma_finalize(&args); goto err; + } migrate_vma_pages(&args); /* * No device finalize step is needed since --=20 2.43.0