From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zou Nan hai Date: Wed, 28 Jun 2006 22:38:22 +0000 Subject: Re: [PATCH] ia64, kexec: allow base of crashkernel to be Message-Id: <1151534302.6052.66.camel@linux-znh> List-Id: References: <20060628110052.GA11751@verge.net.au> In-Reply-To: <20060628110052.GA11751@verge.net.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Wed, 2006-06-28 at 19:00, Horms wrote: > The crashkernel command line parameter accepts a size and base address for > the memory region that is reserved to be used as the memory space for a > crash kernel. At this time, on some architectures, notably i386 and x86_64, > the base address of the crash kernel needs to be modified at compile time > to match the base address passed to crashkernel. However, on ia64 the > crash kernel does not need to be relocated at compile time, thus > there the base address of the crashkernel region does not need to be fixed. > > This patch allows the base address of crashkernel to be determined at boot > time if the base address passed on the command line is 0. Otherwise > the specified base address will be used, as is currently the case. > > The advantage is that the region layout may vary from machine to machine, > and finding a place for the crashkernel is a manual process. This eliminates > that manual work, and I expect will make life slightly easier for distros. > > I would like to note that currently it will try and place the crashkernel > region inside the first "System RAM" region that has space. I am not > sure if there should be a lower or upper bond on the crashkernel base address, > but it will be trivial to add to the arguments passed to allocate_region() > if necessary. > I think there is no upper and lower limit of crash kernel base address, but the base address should be aligned to 64M. which is max(max possible IA64_GRANULE_SIZE, KERNEL_TR_PAGE_SIZE) > Signed-Off-By: Horms > > arch/ia64/kernel/efi.c | 37 +++++++++++++++++++++++++++++++++---- > 1 file changed, 33 insertions(+), 4 deletions(-) >