From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f174.google.com (mail-qk0-f174.google.com [209.85.220.174]) by kanga.kvack.org (Postfix) with ESMTP id 258826B0253 for ; Mon, 17 Aug 2015 09:32:32 -0400 (EDT) Received: by qkfj126 with SMTP id j126so46348451qkf.0 for ; Mon, 17 Aug 2015 06:32:31 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id h184si25181901qhc.21.2015.08.17.06.32.30 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 17 Aug 2015 06:32:30 -0700 (PDT) Message-ID: <1439818347.3153.95.camel@redhat.com> Subject: Re: [PATCH V3 2/3] arm64: support initrd outside kernel linear map From: Mark Salter Date: Mon, 17 Aug 2015 09:32:27 -0400 In-Reply-To: <20150817112256.GH1688@arm.com> References: <1439758168-29427-1-git-send-email-msalter@redhat.com> <1439758168-29427-3-git-send-email-msalter@redhat.com> <20150817112256.GH1688@arm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Will Deacon Cc: Catalin Marinas , "x86@kernel.org" , Andrew Morton , Arnd Bergmann , Ard Biesheuvel , Mark Rutland , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-mm@kvack.org" , "linux-arch@vger.kernel.org" On Mon, 2015-08-17 at 12:22 +0100, Will Deacon wrote: > Hi Mark, > > On Sun, Aug 16, 2015 at 09:49:27PM +0100, Mark Salter wrote: > > The use of mem= could leave part or all of the initrd outside of > > the kernel linear map. This will lead to an error when unpacking > > the initrd and a probable failure to boot. This patch catches that > > situation and relocates the initrd to be fully within the linear > > map. > > > > Signed-off-by: Mark Salter > > --- > > arch/arm64/kernel/setup.c | 59 > > +++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 59 insertions(+) > > > > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > > index f3067d4..5f45fd9 100644 > > --- a/arch/arm64/kernel/setup.c > > +++ b/arch/arm64/kernel/setup.c > > @@ -359,6 +359,64 @@ static void __init > > request_standard_resources(void) > > } > > } > > > > +#ifdef CONFIG_BLK_DEV_INITRD > > +/* > > + * Relocate initrd if it is not completely within the linear mapping. > > + * This would be the case if mem= cuts out all or part of it. > > + */ > > +static void __init relocate_initrd(void) > > +{ > > + phys_addr_t orig_start = __virt_to_phys(initrd_start); > > + phys_addr_t orig_end = __virt_to_phys(initrd_end); > > Any particular reason to use the __* variants here? To avoid need to cast initrd_{start,end} to pointer. > > > + phys_addr_t ram_end = memblock_end_of_DRAM(); > > + phys_addr_t new_start; > > + unsigned long size, to_free = 0; > > + void *dest; > > + > > + if (orig_end <= ram_end) > > + return; > > + > > + /* Note if any of original initrd will freeing below */ > > The comment doesn't make sense. No it doesn't. > > > + if (orig_start < ram_end) > > + to_free = ram_end - orig_start; > > + > > + size = orig_end - orig_start; > > + > > + /* initrd needs to be relocated completely inside linear > > mapping */ > > + new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn), > > + size, PAGE_SIZE); > > + if (!new_start) > > + panic("Cannot relocate initrd of size %ld\n", size); > > + memblock_reserve(new_start, size); > > + > > + initrd_start = __phys_to_virt(new_start); > > + initrd_end = initrd_start + size; > > + > > + pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n", > > + orig_start, orig_start + size - 1, > > + new_start, new_start + size - 1); > > + > > + dest = (void *)initrd_start; > > + > > + if (to_free) { > > + memcpy(dest, (void *)__phys_to_virt(orig_start), > > to_free); > > + dest += to_free; > > + } > > + > > + copy_from_early_mem(dest, orig_start + to_free, size - > > to_free); > > + > > + if (to_free) { > > + pr_info("Freeing original RAMDISK from [%llx-%llx]\n", > > + orig_start, orig_start + to_free - 1); > > + memblock_free(orig_start, to_free); > > + } > > +} > > +#else > > +static inline void __init reserve_initrd(void) > > relocate_initrd ? Yes Thanks, will fix that and the comment. -- 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