Revert "ACPI: Add memory semantics to acpi_os_map_memory()"
authorJia He <justin.he@arm.com>
Thu, 23 Sep 2021 03:35:57 +0000 (11:35 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Thu, 23 Sep 2021 18:39:36 +0000 (20:39 +0200)
commit12064c1768439fa0882547010afae6b52aafa7af
tree7124338fd560de71519fc6baa5b0d1abad2c4eaf
parente4e737bb5c170df6135a127739a9e6148ee3da82
Revert "ACPI: Add memory semantics to acpi_os_map_memory()"

This reverts commit 437b38c51162f8b87beb28a833c4d5dc85fa864e.

The memory semantics added in commit 437b38c51162 causes SystemMemory
Operation region, whose address range is not described in the EFI memory
map to be mapped as NormalNC memory on arm64 platforms (through
acpi_os_map_memory() in acpi_ex_system_memory_space_handler()).

This triggers the following abort on an ARM64 Ampere eMAG machine,
because presumably the physical address range area backing the Opregion
does not support NormalNC memory attributes driven on the bus.

 Internal error: synchronous external abort: 96000410 [#1] SMP
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.14.0+ #462
 Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 0.14 02/22/2019
 pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[...snip...]
 Call trace:
  acpi_ex_system_memory_space_handler+0x26c/0x2c8
  acpi_ev_address_space_dispatch+0x228/0x2c4
  acpi_ex_access_region+0x114/0x268
  acpi_ex_field_datum_io+0x128/0x1b8
  acpi_ex_extract_from_field+0x14c/0x2ac
  acpi_ex_read_data_from_field+0x190/0x1b8
  acpi_ex_resolve_node_to_value+0x1ec/0x288
  acpi_ex_resolve_to_value+0x250/0x274
  acpi_ds_evaluate_name_path+0xac/0x124
  acpi_ds_exec_end_op+0x90/0x410
  acpi_ps_parse_loop+0x4ac/0x5d8
  acpi_ps_parse_aml+0xe0/0x2c8
  acpi_ps_execute_method+0x19c/0x1ac
  acpi_ns_evaluate+0x1f8/0x26c
  acpi_ns_init_one_device+0x104/0x140
  acpi_ns_walk_namespace+0x158/0x1d0
  acpi_ns_initialize_devices+0x194/0x218
  acpi_initialize_objects+0x48/0x50
  acpi_init+0xe0/0x498

If the Opregion address range is not present in the EFI memory map there
is no way for us to determine the memory attributes to use to map it -
defaulting to NormalNC does not work (and it is not correct on a memory
region that may have read side-effects) and therefore commit
437b38c51162 should be reverted, which means reverting back to the
original behavior whereby address ranges that are mapped using
acpi_os_map_memory() default to the safe devicenGnRnE attributes on
ARM64 if the mapped address range is not defined in the EFI memory map.

Fixes: 437b38c51162 ("ACPI: Add memory semantics to acpi_os_map_memory()")
Signed-off-by: Jia He <justin.he@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arch/arm64/include/asm/acpi.h
arch/arm64/kernel/acpi.c
drivers/acpi/osl.c
include/acpi/acpi_io.h