From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by ti-out-0910.google.com with SMTP id j3so1535919tid.8 for ; Mon, 16 Jun 2008 01:08:59 -0700 (PDT) Message-ID: Date: Mon, 16 Jun 2008 16:08:59 +0800 From: "Dave Young" Subject: Re: [PATCH] kernel parameter vmalloc size fix In-Reply-To: <20080616080131.GC25632@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080616042528.GA3003@darkstar.te-china.tietoenator.com> <20080616080131.GC25632@elte.hu> Sender: owner-linux-mm@kvack.org Return-Path: To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, hpa@zytor.com, the arch/x86 maintainers List-ID: On Mon, Jun 16, 2008 at 4:01 PM, Ingo Molnar wrote: > > * Dave Young wrote: > >> booting kernel with vmalloc=[any size<=16m] will oops. >> >> It's due to the vm area hole. >> >> In include/asm-x86/pgtable_32.h: >> #define VMALLOC_OFFSET (8 * 1024 * 1024) >> #define VMALLOC_START (((unsigned long)high_memory + 2 * VMALLOC_OFFSET - 1) \ >> & ~(VMALLOC_OFFSET - 1)) >> >> BUG_ON in arch/x86/mm/init_32.c will be triggered: >> BUG_ON((unsigned long)high_memory > VMALLOC_START); >> >> Fixed by return -EINVAL for invalid parameter > > hm. Why dont we instead add the size of the hole to the > __VMALLOC_RESERVE value instead? There's nothing inherently bad about > using vmalloc=16m. The VM area hole is really a kernel-internal > abstraction that should not be visible in the usage of the parameter. Good suggestion, thanks. I will rewrite the patch and send. -- Regards dave -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org