Re: [BUG] acpica: ltp_acpi test case causes kernel crash at acpi_ns_walk_namespace

From: Rafael J. Wysocki
Date: Tue Dec 12 2017 - 18:46:39 EST


On Tuesday, December 12, 2017 4:59:19 PM CET Vadim Lomovtsev wrote:
> Hi guys,
>
> While running LTP tests I've faced kernel crash caused by ltp_acpi test case.
> I have ACPI support enabled in kernel but kernel is boot with FDT having ACPI
> disabled. The ltp_acpi test case application is built along with ltp_acpi_cmds
> module to run ACPI tests.
>
> So my question is - should we update acpica implementation at kernel side by
> adding 'acpi_disabled' variable checking to the 'acpi_get_devices' function (see
> patch next to this email, maybe not a good approach) or this should be fixed at LTP
> side so the ltp_acpi_cmds should be updated in order to check if acpi is enabled
> before running tests ?

There should be a check preventing acpi_get_devices() from being called in the
acpi_disabled case.

acpi_disabled is Linux-specific and the ACPICA code isn't, so the code calling
ACPICA functions should check acpi_disabled when necessary.

Thanks,
Rafael