From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [patch v2 2/2] s390: Add architecture code for unmapping crashkernel memory From: Michael Holzheu Reply-To: holzheu@linux.vnet.ibm.com In-Reply-To: <20110914182902.GA32658@redhat.com> References: <20110913132635.063397500@linux.vnet.ibm.com> <20110913132654.157278466@linux.vnet.ibm.com> <20110913145218.659f9e21.akpm@google.com> <1315990708.3367.14.camel@br98xy6r> <20110914182902.GA32658@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 15 Sep 2011 10:48:03 +0200 Message-ID: <1316076483.3526.4.camel@br98xy6r> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Vivek Goyal Cc: Andrew Morton , ebiederm@xmission.com, mahesh@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Andrew Morton List-ID: Hello Vivek, Andrew, On Wed, 2011-09-14 at 14:29 -0400, Vivek Goyal wrote: > On Wed, Sep 14, 2011 at 10:58:28AM +0200, Michael Holzheu wrote: > > > Why not make this unconditional, for all architectures which support > > > hugepages? ie: > > > > > > #ifdef HPAGE_SIZE > > > #define KEXEC_CRASH_MEM_ALIGN HPAGE_SIZE > > > #else > > > #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE > > > #endif > > > > > in include/linux/kexec.h? > > > > > > IOW, what are the compromises here? > > > > If we would do it that way, crashkernel memory on architectures that > > support large pages but do not support unmapping of crashkernel memory > > would always be aligned to HPAGE_SIZE. But only PAGE_SIZE alignment > > would be necessary in that case. > > > > If that is acceptable I have no problem to define that unconditional for > > all architectures. Vivek what do you think? > > As PAGE_SIZE alignment is sufficient for rest of the architecture, I > am fine with keeping it in arch dependent files. Ok fine. So I will resend the two patches including Andrew's resource_size() fix and keep KEXEC_CRASH_MEM_ALIGN definition architecture dependent. Michael