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| author | Takahisa Tanaka <mc74hc00@gmail.com> | 2013-01-14 11:01:57 +0900 |
|---|---|---|
| committer | Wim Van Sebroeck <wim@iguana.be> | 2013-03-01 12:19:26 +0100 |
| commit | 10ab329b5db7e592a3a60b4594e4e5f40b60c45c (patch) | |
| tree | 52e8c155fe20f181df604c3ac5cefa2a306c0bbb /drivers/watchdog | |
| parent | 6737176569d1d6356c644694d60ea2b265cb3870 (diff) | |
| download | linux-10ab329b5db7e592a3a60b4594e4e5f40b60c45c.tar.bz2 | |
watchdog: sp5100_tco: Fix wrong indirect I/O access for getting value of reserved bits
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@gmail.com>
Tested-by: Paul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: stable <stable@vger.kernel.org>
Diffstat (limited to 'drivers/watchdog')
| -rw-r--r-- | drivers/watchdog/sp5100_tco.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c index 2b0e000d4377..5dfe86ebdc8b 100644 --- a/drivers/watchdog/sp5100_tco.c +++ b/drivers/watchdog/sp5100_tco.c @@ -500,14 +500,15 @@ static unsigned char sp5100_tco_setupdevice(void) /* 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); |