On 07/21/2017 05:56 PM, Andy Shevchenko wrote: > On Fri, Jul 21, 2017 at 12:41 PM, Song liwei <liwei.song@xxxxxxxxxxxxx> wrote: > >> [Firmware Bug]: APEI: Invalid bit width + offset in GAR [0xb2/16/0/1/1] >> >> This is due to an 8-bit access width is specified for a 16-bit register, >> Do bit_width check just like what the original commit have done. > >> else if (bit_width == 64 && bit_offset == 0 && (*paddr & 0x07) == 0 && >> *access_bit_width < 64) >> *access_bit_width = 64; >> + else if (bit_width == 16 && bit_offset == 0 && (*paddr & 0x01) == 0 && >> + *access_bit_width < 16) >> + *access_bit_width = 16; > > Wouldn't be better to rearrange that it will go in a sequence > (16,32,64 or 64,32,16) ? > > or move bit_offset == 0 into external condion > > /* Fixup common BIOS bug */ > if (bit_offset == 0) { > if (bit_width == 16 && (*paddr & 0x01) == 0 && *access_bit_width < 16) > *access_bit_width = 16; > else if (bit_width == 32 && (*paddr & 0x03) == 0 && > *access_bit_width < 32) > *access_bit_width = 32; > else if (bit_width == 64 && (*paddr & 0x07) == 0 && > *access_bit_width < 64) > *access_bit_width = 64; > } > > > It might be (I'm not sure it will make it better, just a side note) > considered to convert each internal conditional to > > ...if (bit_width == XX && (*paddr & YY) == 0) > *access_bit_width = max(*access_bit_width, bit_width); Hi Andy, Thanks for your suggestion, what about the condition like the following? The main bug in bios is bit_width is not comfortable with access_bit_width So check it first. if (*access_bit_width < bit_width && bit_offset == 0) { if ((bit_width == 16 && (*paddr & 0x01) == 0) || (bit_width == 32 && (*paddr & 0x03) == 0) || (bit_width == 64 && (*paddr & 0x07) == 0)) *access_bit_width = bit_width; } Thanks, Liwei. > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html