From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gregory Haskins Subject: [PATCH] Subject: x86: Move crashkernel reservation before dma32_reserve_bootmem() Date: Mon, 25 Aug 2008 08:58:31 -0400 Message-ID: <20080825125639.26874.80623.stgit@dev.haskins.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, Bernhard Walle , Gregory Haskins To: srostedt@redhat.com, mingo@elte.hu, tglx@linutronix.de Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org Hi Steven, Ingo, Thomas, Bernard (cc'd) sent me this patch for 26.3-rt3 to fix an issue where a kdump kernel will fail to load, thereby disabling the crashdump feature. Please consider this patch for -rt4. IIUC, this patch is already upstream in the .27 series. -Greg ----------------- From: Bernhard Walle On a x86-64 machine (nothing special I could encounter) I had the problem that crashkernel reservation with the usual "64M@16M" failed. While debugging that, I encountered that dma32_reserve_bootmem() reserves a memory region which is in that area. Because dma32_reserve_bootmem() does not rely on a specific offset but crashkernel does, it makes sense to move the crashkernel reservation up a bit. I tested that patch and it works without problems. I don't see any negative effects of that move, but maybe I oversaw something ... While the long-term solution is to make the crashkernel reservation dynamic (which is already done in -tip), this bug should be fixed also short-term for 2.6.26 (or 2.6.26-stable if it's too short), and that's why I made that patch. Signed-off-by: Bernhard Walle Signed-off-by: Gregory Haskins --- arch/x86/kernel/setup_64.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c index 6dff128..158cefe 100644 --- a/arch/x86/kernel/setup_64.c +++ b/arch/x86/kernel/setup_64.c @@ -444,6 +444,12 @@ void __init setup_arch(char **cmdline_p) contig_initmem_init(0, end_pfn); #endif + /* + * dma32_reserve_bootmem() allocates bootmem which may conflict + * with the crashkernel command line, so do that before + */ + reserve_crashkernel(); + dma32_reserve_bootmem(); #ifdef CONFIG_ACPI_SLEEP @@ -484,7 +490,6 @@ void __init setup_arch(char **cmdline_p) } } #endif - reserve_crashkernel(); reserve_ibft_region();