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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21BCAC3527D for ; Tue, 12 Apr 2022 08:40:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383351AbiDLIgq (ORCPT ); Tue, 12 Apr 2022 04:36:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352185AbiDLHhN (ORCPT ); Tue, 12 Apr 2022 03:37:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6760517C5; Tue, 12 Apr 2022 00:09:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0F82E61701; Tue, 12 Apr 2022 07:09:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CC69C385A1; Tue, 12 Apr 2022 07:09:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649747377; bh=0e/d5D+R6S4UcwLPGQgbNjXmPk3xN2N8EX8QHHUO7/k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dO4MxluPah4l814KyKPL5YFZKsZpG3dU374S5ApNJ8vDYiB6ede+4ZG788Vsx6KFD XmG0eTIecErjeAn/BCLRsfpZcCc17CoxR+shGfGCdNzlngblJyUcMn/qnFax6a7gLR s2RqF1jtvE6/KPkfBg/B2k6lFaKNjMYQeeew9uSc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Abdul haleem , Sourabh Jain , Michael Ellerman , Sasha Levin Subject: [PATCH 5.17 056/343] powerpc: Set crashkernel offset to mid of RMA region Date: Tue, 12 Apr 2022 08:27:54 +0200 Message-Id: <20220412062952.721929501@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220412062951.095765152@linuxfoundation.org> References: <20220412062951.095765152@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sourabh Jain [ Upstream commit 7c5ed82b800d8615cdda00729e7b62e5899f0b13 ] On large config LPARs (having 192 and more cores), Linux fails to boot due to insufficient memory in the first memblock. It is due to the memory reservation for the crash kernel which starts at 128MB offset of the first memblock. This memory reservation for the crash kernel doesn't leave enough space in the first memblock to accommodate other essential system resources. The crash kernel start address was set to 128MB offset by default to ensure that the crash kernel get some memory below the RMA region which is used to be of size 256MB. But given that the RMA region size can be 512MB or more, setting the crash kernel offset to mid of RMA size will leave enough space for the kernel to allocate memory for other system resources. Since the above crash kernel offset change is only applicable to the LPAR platform, the LPAR feature detection is pushed before the crash kernel reservation. The rest of LPAR specific initialization will still be done during pseries_probe_fw_features as usual. This patch is dependent on changes to paca allocation for boot CPU. It expect boot CPU to discover 1T segment support which is introduced by the patch posted here: https://lists.ozlabs.org/pipermail/linuxppc-dev/2022-January/239175.html Reported-by: Abdul haleem Signed-off-by: Sourabh Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220204085601.107257-1-sourabhjain@linux.ibm.com Signed-off-by: Sasha Levin --- arch/powerpc/kernel/rtas.c | 6 ++++++ arch/powerpc/kexec/core.c | 15 +++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index 733e6ef36758..1f42aabbbab3 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -1313,6 +1313,12 @@ int __init early_init_dt_scan_rtas(unsigned long node, entryp = of_get_flat_dt_prop(node, "linux,rtas-entry", NULL); sizep = of_get_flat_dt_prop(node, "rtas-size", NULL); +#ifdef CONFIG_PPC64 + /* need this feature to decide the crashkernel offset */ + if (of_get_flat_dt_prop(node, "ibm,hypertas-functions", NULL)) + powerpc_firmware_features |= FW_FEATURE_LPAR; +#endif + if (basep && entryp && sizep) { rtas.base = *basep; rtas.entry = *entryp; diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c index 8b68d9f91a03..abf5897ae88c 100644 --- a/arch/powerpc/kexec/core.c +++ b/arch/powerpc/kexec/core.c @@ -134,11 +134,18 @@ void __init reserve_crashkernel(void) if (!crashk_res.start) { #ifdef CONFIG_PPC64 /* - * On 64bit we split the RMO in half but cap it at half of - * a small SLB (128MB) since the crash kernel needs to place - * itself and some stacks to be in the first segment. + * On the LPAR platform place the crash kernel to mid of + * RMA size (512MB or more) to ensure the crash kernel + * gets enough space to place itself and some stack to be + * in the first segment. At the same time normal kernel + * also get enough space to allocate memory for essential + * system resource in the first segment. Keep the crash + * kernel starts at 128MB offset on other platforms. */ - crashk_res.start = min(0x8000000ULL, (ppc64_rma_size / 2)); + if (firmware_has_feature(FW_FEATURE_LPAR)) + crashk_res.start = ppc64_rma_size / 2; + else + crashk_res.start = min(0x8000000ULL, (ppc64_rma_size / 2)); #else crashk_res.start = KDUMP_KERNELBASE; #endif -- 2.35.1