From: Jean Delvare <jdelvare@xxxxxxx> Many firmwares have a common register definition bug where 8-bit access width is specified for a 32-bit register. Ideally this should be fixed in the BIOS, but earlier versions of the kernel did not complain, so fix that up silently. This closes kernel bug #43282: https://bugzilla.kernel.org/show_bug.cgi?id=43282 Signed-off-by: Jean Delvare <jdelvare@xxxxxxx> Acked-by: Huang Ying <ying.huang@xxxxxxxxx> Acked-by: Gary Hade <garyhade@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx [3.4+] Signed-off-by: Len Brown <len.brown@xxxxxxxxx> --- drivers/acpi/apei/apei-base.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c index 6686b1e..00a7836 100644 --- a/drivers/acpi/apei/apei-base.c +++ b/drivers/acpi/apei/apei-base.c @@ -586,6 +586,11 @@ static int apei_check_gar(struct acpi_generic_address *reg, u64 *paddr, } *access_bit_width = 1UL << (access_size_code + 2); + /* Fixup common BIOS bug */ + if (bit_width == 32 && bit_offset == 0 && (*paddr & 0x03) == 0 && + *access_bit_width < 32) + *access_bit_width = 32; + if ((bit_width + bit_offset) > *access_bit_width) { pr_warning(FW_BUG APEI_PFX "Invalid bit width + offset in GAR [0x%llx/%u/%u/%u/%u]\n", -- 1.7.12.rc0
