On 06/30/2015 11:07 AM, Sudeep Holla wrote: > Hi Al, > > On 18/06/15 23:36, Al Stone wrote: >> In the ACPI 5.1 version of the spec, the struct for the GICC subtable >> (struct acpi_madt_generic_interrupt) of the MADT is 76 bytes long; in >> ACPI 6.0, the struct is 80 bytes long. But, there is only one definition >> in ACPICA for this struct -- and that is the 6.0 version. Hence, when >> BAD_MADT_ENTRY() compares the struct size to the length in the GICC >> subtable, it fails if 5.1 structs are in use, and there are systems in >> the wild that have them. >> >> Note that this was found in linux-next and these patches apply against >> that tree and the arm64 kernel tree; 4.1-rc8 does not appear to have this >> problem since it still has the 5.1 struct definition. >> >> Even though there is precendent in ia64 code for ignoring the changes in >> size, this patch set instead tries to verify correctness. The first patch >> in the set adds macros for easily using the ACPI spec version. The second >> patch adds the BAD_MADT_GICC_ENTRY() macro that uses the version macros to >> check the GICC subtable only, accounting for the difference in specification >> versions that are possible. The final patch replaces BAD_MADT_ENTRY usage >> with the BAD_MADT_GICC_ENTRY macro in arm64 code, which is currently the >> only architecture affected. The BAD_MADT_ENTRY() will continue to work as >> is for all other MADT subtables. >> > > We need to get this series or a patch to remove the check(similar to > ia64) based on what Rafael prefers. Without that, platforms using ACPI > on ARM64 fails to boot with latest mainline. This blocks any testing on > ARM64/ACPI systems. > > Regards, > Sudeep I have not received any other feedback than some Reviewed-bys from Hanjun and an ACK from Will for the arm64 patch. And absolutely agreed: this is a blocker for arm64/ACPI, starting with the ACPICA 20150515 patches which appear to have gone in with 4.2-rc1. Rafael? Ping? Do we need these to go through your tree or the arm64 tree? Without this series (or an ia64-like solution), we have ACPI systems in the field that cannot boot. -- ciao, al ----------------------------------- Al Stone Software Engineer Red Hat, Inc. ahs3@xxxxxxxxxx ----------------------------------- -- 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
