Commit 78f1699 (ACPI: processor: call _PDC early) blindly walks
the namespace and calls _PDC on every processor object it finds.
This change may cause issues on platforms that declare dummy
values for SSDTs on non-present processors (disabled in MADT).
When we call _PDC and dynamically attempt to execute the AML
Load() op on these dummy SSDTs, there's no telling what might
happen.
Rather than finding every platform that has bogus SSDTs, restrict
early _PDC calls to platforms that are known to need early
evaluation of _PDC.
This is a minimal, temporary fix (given the context of the
current release cycle). A real solution of checking the MADT for
non-present processors will be written for the next merge window.
References:
http://bugzilla.kernel.org/show_bug.cgi?id=14710http://bugzilla.kernel.org/show_bug.cgi?id=14954
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Alex Chiang introduced acpi_early_processor_set_pdc() in commit:
ACPI: processor: call _PDC early
78f1699659
But this results in a section mismatch:
WARNING: drivers/acpi/acpi.o(.text+0xa9c1): Section mismatch in reference from the
function acpi_early_processor_set_pdc() to the variable .cpuinit.data:processor_idle_dmi_table
The function acpi_early_processor_set_pdc() references
the variable __cpuinitdata processor_idle_dmi_table.
This is often because acpi_early_processor_set_pdc lacks a __cpuinitdata
annotation or the annotation of processor_idle_dmi_table is wrong.
The only caller of acpi_early_processor_set_pdc() is acpi_bus_init() which
is an "__init" function. So the correct fix here is to mark
acpi_early_processor_set_pdc() "__init" too.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
When calling _PDC, we really only need the handle to the processor
to call the method; we don't look at any other parts of the
struct acpi_processor * given to us.
In the early path, when we walk the namespace, we are given the
handle directly, so just pass it through to acpi_processor_set_pdc()
without stuffing it into a wasteful struct acpi_processor allocated
on the stack each time
This saves 2834 bytes of stack.
Update the interface accordingly.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We have the acpi_object_list * right there in acpi_processor_set_pdc()
so it doesn't seem necessary for an entire helper function just to
free it.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
acpi_processor_eval_pdc() really only needs a handle and an
acpi_object_list * to do its work.
No need to pass in a struct acpi_processor *, so let's be more specific
about what we want.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
acpi_processor_init_pdc() isn't really doing anything interesting
with the struct acpi_processor * parameter. Its real job is to allocate
the buffer for the _PDC bits.
So rename the function to acpi_processor_alloc_pdc(), and just return
the struct acpi_object_list * it's supposed to allocate.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The x86 and ia64 implementations of the function in $subject are
exactly the same.
Also, since the arch-specific implementations of setting _PDC have
been completely hollowed out, remove the empty shells.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The only thing arch-specific about calling _PDC is what bits get
set in the input obj_list buffer.
There's no need for several levels of indirection to twiddle those
bits. Additionally, since we're just messing around with a buffer,
we can simplify the interface; no need to pass around the entire
struct acpi_processor * just to get at the buffer.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Both x86 and ia64 initialize _PDC with mostly common bit settings.
Factor out the common settings and leave the arch-specific ones alone.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The x86 and ia64 implementations of arch_acpi_processor_init_pdc()
are almost exactly the same. The only difference is in what bits
they set in obj_list buffer.
Combine the boilerplate memory management code, and leave the
arch-specific bit twiddling in separate implementations.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
arch dependent helper function that tells us if we should attempt to
evaluate _PDC on this machine or not.
The x86 implementation assumes that the CPUs in the machine must be
homogeneous, and that you cannot mix CPUs of different vendors.
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We discovered that at least one machine (HP Envy), methods in the DSDT
attempt to call external methods defined in a dynamically loaded SSDT.
Unfortunately, the DSDT methods we are trying to call are part of the
EC initialization, which happens very early, and the the dynamic SSDT
is only loaded when a processor _PDC method runs much later.
This results in namespace lookup errors for the (as of yet) undefined
methods.
Since Windows doesn't have any issues with this machine, we take it
as a hint that they must be evaluating _PDC much earlier than we are.
Thus, the proper thing for Linux to do should be to match the Windows
implementation more closely.
Provide a mechanism to call _PDC before we enable the EC. Doing so loads
the dynamic tables, and allows the EC to be enabled correctly.
The ACPI processor driver will still evaluate _PDC in its .add() method
to cover the hotplug case.
Resolves: http://bugzilla.kernel.org/show_bug.cgi?id=14824
Cc: ming.m.lin@intel.com
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>