From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amerigo Wang Date: Thu, 06 Aug 2009 02:05:44 +0000 Subject: Re: [Patch 0/7] Implement crashkernel=auto Message-Id: <4A7A3A78.7080200@redhat.com> List-Id: References: <20090805112123.6552.73574.sendpatchset@localhost.localdomain> <20090805140408.GJ7259@hmsreliant.think-freely.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Eric W. Biederman" Cc: Neil Horman , linux-kernel@vger.kernel.org, tony.luck@intel.com, linux-ia64@vger.kernel.org, akpm@linux-foundation.org, Ingo Molnar , Anton Vorontsov Eric W. Biederman wrote: > Neil Horman writes: > >> You could of >> course boot the installer kernel with a crashkernel line pre-selected suppose, >> but then you have to go to the trouble of figuring that allocation size out each >> time. This gives you a nice convienent way to get a reasonable block of memory >> without the need to do all that extra work. >> > > My big concern is that you are moving policy into the kernel, when it isn't at > all clear that policy is the right thing to do, and the existing mechanisms give > you enough rope to do this all in userspace. > How? This doesn't remove the existing mechanism, just provides a new choice for user like me who doesn't know how much memory should be reserved, or who simply doesn't want to concern this since he/she has very enough memory. > You also have to build (or at least load) the whole kdump image after > the system boots, and configure someplace for this to be saved. > > What class of problems do you expect to catch with this? > Again, try to save the user from choosing numbers for "crashkernel=". > What has me puzzled is that the mkdumprd that ships with fedora isn't > usable without patching, and it seems to be steadily getting worse. Please explain why it is not usable? The patch won't break the userspace, since it modifies the "crashkernel=" command line dynamically. Thanks.