From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78BFDC2D0C6 for ; Wed, 11 Dec 2019 16:08:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4DA77222C4 for ; Wed, 11 Dec 2019 16:08:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576080511; bh=zqTUOEFIaUW8OAamEIz8kTudhAMpMV0HwrLv/f5BdIc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2BnI7gr5dimHpWGQgxxXG+ltUCJD3QflzM2SmbdzpeWG9gtzHZZIFKTp/XigPRD3i a2XOncXptdNeBK4n0g60eUXwXz3/WnYnJktiT8AmoJqMX1IwglE3RCJuQjQUeQWr4y J3JpsdEhVx+7vTSm7AlBuTNT+DcPelkO/VPxvfS4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731122AbfLKQI0 (ORCPT ); Wed, 11 Dec 2019 11:08:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:33612 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731080AbfLKPMR (ORCPT ); Wed, 11 Dec 2019 10:12:17 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6684422B48; Wed, 11 Dec 2019 15:12:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576077137; bh=zqTUOEFIaUW8OAamEIz8kTudhAMpMV0HwrLv/f5BdIc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TJmzM2QUTSy+ztPrGFXFHGJw8qt6yebw32cpfU3/HKtWAjI1MNq6Z1ygcrP3N/ZzV sXwqiyMhyaItWpvJDKRBdzjUi69JriCDaENqY8LokVcghD3YEGOFzxbUwu6hKnMgoD q0F562TwzlIcgOzGLHeyNFe44WRiSUhutDjJQuFw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Aneesh Kumar K.V" , Michael Ellerman , Sasha Levin , linuxppc-dev@lists.ozlabs.org Subject: [PATCH AUTOSEL 5.4 024/134] powerpc/pseries: Don't fail hash page table insert for bolted mapping Date: Wed, 11 Dec 2019 10:10:00 -0500 Message-Id: <20191211151150.19073-24-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191211151150.19073-1-sashal@kernel.org> References: <20191211151150.19073-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: "Aneesh Kumar K.V" [ Upstream commit 75838a3290cd4ebbd1f567f310ba04b6ef017ce4 ] If the hypervisor returned H_PTEG_FULL for H_ENTER hcall, retry a hash page table insert by removing a random entry from the group. After some runtime, it is very well possible to find all the 8 hash page table entry slot in the hpte group used for mapping. Don't fail a bolted entry insert in that case. With Storage class memory a user can find this error easily since a namespace enable/disable is equivalent to memory add/remove. This results in failures as reported below: $ ndctl create-namespace -r region1 -t pmem -m devdax -a 65536 -s 100M libndctl: ndctl_dax_enable: dax1.3: failed to enable Error: namespace1.2: failed to enable failed to create namespace: No such device or address In kernel log we find the details as below: Unable to create mapping for hot added memory 0xc000042006000000..0xc00004200d000000: -1 dax_pmem: probe of dax1.3 failed with error -14 This indicates that we failed to create a bolted hash table entry for direct-map address backing the namespace. We also observe failures such that not all namespaces will be enabled with ndctl enable-namespace all command. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191024093542.29777-2-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin --- arch/powerpc/mm/book3s64/hash_utils.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index 6c123760164e8..6e5a769ebcb80 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -294,7 +294,14 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend, ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, HPTE_V_BOLTED, psize, psize, ssize); - + if (ret == -1) { + /* Try to remove a non bolted entry */ + ret = mmu_hash_ops.hpte_remove(hpteg); + if (ret != -1) + ret = mmu_hash_ops.hpte_insert(hpteg, vpn, paddr, tprot, + HPTE_V_BOLTED, psize, psize, + ssize); + } if (ret < 0) break; -- 2.20.1