This is a note to let you know that I've just added the patch titled watchdog: sp5100_tco: Fix wrong indirect I/O access for getting value of reserved bits to the 3.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: watchdog-sp5100_tco-fix-wrong-indirect-i-o-access-for-getting-value-of-reserved-bits.patch and it can be found in the queue-3.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 10ab329b5db7e592a3a60b4594e4e5f40b60c45c Mon Sep 17 00:00:00 2001 From: Takahisa Tanaka <mc74hc00@xxxxxxxxx> Date: Mon, 14 Jan 2013 11:01:57 +0900 Subject: watchdog: sp5100_tco: Fix wrong indirect I/O access for getting value of reserved bits From: Takahisa Tanaka <mc74hc00@xxxxxxxxx> 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 <mc74hc00@xxxxxxxxx> Tested-by: Paul Menzel <paulepanter@xxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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); Patches currently in stable-queue which might be from mc74hc00@xxxxxxxxx are queue-3.8/watchdog-sp5100_tco-fix-wrong-indirect-i-o-access-for-getting-value-of-reserved-bits.patch queue-3.8/watchdog-sp5100_tco-write-back-the-original-value-to-reserved-bits-instead-of-zero.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html