Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751500AbaK1L3w (ORCPT ); Fri, 28 Nov 2014 06:29:52 -0500 Received: from 8bytes.org ([81.169.241.247]:40160 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750984AbaK1L3W (ORCPT ); Fri, 28 Nov 2014 06:29:22 -0500 From: Joerg Roedel To: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Konrad Rzeszutek Wilk Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Joerg Roedel , Joerg Roedel Subject: [PATCH 0/3] Fix kdump failures with crashkernel=high Date: Fri, 28 Nov 2014 12:29:06 +0100 Message-Id: <1417174149-31210-1-git-send-email-joro@8bytes.org> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, here is a patch-set to fix failed kdump kernel boots when the systems was booted with crashkernel=X,high. On those systems the kernel allocates only 72MiB of low-memory for DMA buffers, which showed to be too low on some systems. The problem is that 64MiB of the low-memory is allocated by swiotlb, leaving 8MB for the page-allocator. But swiotlb tries to allocate DMA memory from the page-allocator first, which fails pretty fast in the boot sequence, causing warnings. This patch-set removes these warnings. But even the 64MiB for swiotlb are eaten up on some systems, so that the default of low-memory allocated for the crash-kernel is increase from 72MB to 256MB (only changing the defaults, can still be overwritten by crashkernel=X,low). This number comes from experiments on the affected systems, 128MiB low-memory was still not enough there, thus I set the value to 256MiB to fix the issues. Any feedback appreciated. Thanks, Joerg Joerg Roedel (3): swiotlb: Warn on allocation failure in swiotlb_alloc_coherent x86, swiotlb: Try coherent allocations with __GFP_NOWARN x86, crash: Allocate enough low-mem when crashkernel=high arch/x86/kernel/pci-swiotlb.c | 8 ++++++++ arch/x86/kernel/setup.c | 5 ++++- lib/swiotlb.c | 11 +++++++++-- 3 files changed, 21 insertions(+), 3 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/