Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933683Ab3CLWdU (ORCPT ); Tue, 12 Mar 2013 18:33:20 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60108 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755781Ab3CLWcn (ORCPT ); Tue, 12 Mar 2013 18:32:43 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takahisa Tanaka , Paul Menzel , Wim Van Sebroeck Subject: [ 010/100] watchdog: sp5100_tco: Fix wrong indirect I/O access for getting value of reserved bits Date: Tue, 12 Mar 2013 15:30:55 -0700 Message-Id: <20130312223124.039360804@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130312223122.884099393@linuxfoundation.org> References: <20130312223122.884099393@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2149 Lines: 56 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Takahisa Tanaka commit 10ab329b5db7e592a3a60b4594e4e5f40b60c45c upstream. In case of SB800 or later chipset and re-programming MMIO address(*), sp5100_tco module may read incorrect value of reserved bit, because the module reads a value from an incorrect I/O address. However, this bug doesn't cause a problem, because when re-programming MMIO address, by chance the module writes zero (this is BIOS's default value) to the low three bits of register. * In most cases, PC with SB8x0 or later chipset doesn't need to re-programming MMIO address, because such PC can enable AcpiMmio and can use 0xfed80b00 for watchdog register base address. This patch fixes this bug. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43176 Signed-off-by: Takahisa Tanaka Tested-by: Paul Menzel Signed-off-by: Wim Van Sebroeck Signed-off-by: Greg Kroah-Hartman --- drivers/watchdog/sp5100_tco.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/watchdog/sp5100_tco.c +++ b/drivers/watchdog/sp5100_tco.c @@ -500,14 +500,15 @@ static unsigned char sp5100_tco_setupdev /* Restore to the low three bits, if chipset is SB8x0(or later) */ if (sp5100_tco_pci->revision >= 0x40) { u8 reserved_bit; - reserved_bit = inb(base_addr) & 0x7; + outb(base_addr+0, index_reg); + reserved_bit = inb(data_reg) & 0x7; val |= (u32)reserved_bit; } /* Re-programming the watchdog timer base address */ outb(base_addr+0, index_reg); /* Low three bits of BASE are reserved */ - outb((val >> 0) & 0xf8, data_reg); + outb((val >> 0) & 0xff, data_reg); outb(base_addr+1, index_reg); outb((val >> 8) & 0xff, data_reg); outb(base_addr+2, index_reg); -- 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/