Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755016AbaGPTAq (ORCPT ); Wed, 16 Jul 2014 15:00:46 -0400 Received: from mail-ig0-f181.google.com ([209.85.213.181]:58487 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753807AbaGPTAm (ORCPT ); Wed, 16 Jul 2014 15:00:42 -0400 MIME-Version: 1.0 In-Reply-To: <53C63139.7000608@kristov.de> References: <53C63139.7000608@kristov.de> From: Bjorn Helgaas Date: Wed, 16 Jul 2014 13:00:21 -0600 Message-ID: Subject: Re: [PATCH 1/1] x86: don't exclude low BIOS area when allocating address space for non-PCI cards To: Christoph Schulz Cc: "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "x86@kernel.org" , Robert Resch Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 16, 2014 at 2:00 AM, Christoph Schulz wrote: > From: Christoph Schulz > > Commit 30919b0bf356a8ee0ef4f7d38ca8ad99b96820b2 ("x86: avoid low BIOS area when > allocating address space") moved the test for resource allocations that fall > within the first 1MB of address space from the PCI-specific path to a generic > path, such that all resource allocations will avoid this area. However, this > breaks ISA cards which need to allocate a memory region within the first 1MB. > An example is the i82365 PCMCIA controller and derivatives like the Ricoh > RF5C296/396 which map part of the PCMCIA socket memory address space into the > first 1MB of system memory address space. They do not work anymore as no usable > memory region exists due to this change: > > Intel ISA PCIC probe: Ricoh RF5C296/396 ISA-to-PCMCIA at port 0x3e0 ofs 0x00, 2 sockets > host opts [0]: none > host opts [1]: none > ISA irqs (scanned) = 3,4,5,9,10 status change on irq 10 > pcmcia_socket pcmcia_socket1: pccard: PCMCIA card inserted into slot 1 > pcmcia_socket pcmcia_socket0: cs: IO port probe 0xc00-0xcff: excluding 0xcf8-0xcff > pcmcia_socket pcmcia_socket0: cs: IO port probe 0xa00-0xaff: clean. > pcmcia_socket pcmcia_socket0: cs: IO port probe 0x100-0x3ff: excluding 0x170-0x177 0x1f0-0x1f7 0x2f8-0x2ff 0x370-0x37f 0x3c0-0x3e7 0x3f0-0x3ff > pcmcia_socket pcmcia_socket0: cs: memory probe 0x0a0000-0x0affff: excluding 0xa0000-0xaffff > pcmcia_socket pcmcia_socket0: cs: memory probe 0x0b0000-0x0bffff: excluding 0xb0000-0xbffff > pcmcia_socket pcmcia_socket0: cs: memory probe 0x0c0000-0x0cffff: excluding 0xc0000-0xcbfff > pcmcia_socket pcmcia_socket0: cs: memory probe 0x0d0000-0x0dffff: clean. > pcmcia_socket pcmcia_socket0: cs: memory probe 0x0e0000-0x0effff: clean. > pcmcia_socket pcmcia_socket0: cs: memory probe 0x60000000-0x60ffffff: clean. > pcmcia_socket pcmcia_socket0: cs: memory probe 0xa0000000-0xa0ffffff: clean. > pcmcia_socket pcmcia_socket1: cs: IO port probe 0xc00-0xcff: excluding 0xcf8-0xcff > pcmcia_socket pcmcia_socket1: cs: IO port probe 0xa00-0xaff: clean. > pcmcia_socket pcmcia_socket1: cs: IO port probe 0x100-0x3ff: excluding 0x170-0x177 0x1f0-0x1f7 0x2f8-0x2ff 0x370-0x37f 0x3c0-0x3e7 0x3f0-0x3ff > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0a0000-0x0affff: excluding 0xa0000-0xaffff > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0b0000-0x0bffff: excluding 0xb0000-0xbffff > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0c0000-0x0cffff: excluding 0xc0000-0xcbfff > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0d0000-0x0dffff: clean. > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0e0000-0x0effff: clean. > pcmcia_socket pcmcia_socket1: cs: memory probe 0x60000000-0x60ffffff: clean. > pcmcia_socket pcmcia_socket1: cs: memory probe 0xa0000000-0xa0ffffff: clean. > pcmcia_socket pcmcia_socket1: cs: memory probe 0x0cc000-0x0effff: excluding 0xe0000-0xeffff > pcmcia_socket pcmcia_socket1: cs: unable to map card memory! > > If filtering out the first 1MB is reverted, everything works as expected. > > Signed-off-by: Christoph Schulz > Tested-by: Robert Resch I applied this to pci/misc for v3.17, thanks. This effectively reverts 30919b0bf356 ("x86: avoid low BIOS area when allocating address space"). I don't see a reference there to a bug fixed by 30919b0bf356, so hopefully reverting it won't reintroduce a bug. > --- > diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c > index 2a26819..80eab01 100644 > --- a/arch/x86/kernel/resource.c > +++ b/arch/x86/kernel/resource.c > @@ -37,10 +37,12 @@ static void remove_e820_regions(struct resource *avail) > > void arch_remove_reservations(struct resource *avail) > { > - /* Trim out BIOS areas (low 1MB and high 2MB) and E820 regions */ > + /* > + * Trim out BIOS area (high 2MB) and E820 regions. We do not remove > + * the low 1MB unconditionally, as this area is needed for some ISA > + * cards requiring a memory range, e.g. the i82365 PCMCIA controller. > + */ > if (avail->flags & IORESOURCE_MEM) { > - if (avail->start < BIOS_END) > - avail->start = BIOS_END; > resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END); > > remove_e820_regions(avail); > diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c > index a19ed92..2ae525e 100644 > --- a/arch/x86/pci/i386.c > +++ b/arch/x86/pci/i386.c > @@ -162,6 +162,10 @@ pcibios_align_resource(void *data, const struct resource *res, > return start; > if (start & 0x300) > start = (start + 0x3ff) & ~0x3ff; > + } else if (res->flags & IORESOURCE_MEM) { > + /* The low 1MB range is reserved for ISA cards */ > + if (start < BIOS_END) > + start = BIOS_END; > } > return start; > } > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/