diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2020-09-29 15:25:22 +0200 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-09-30 22:27:51 +0100 |
| commit | a509a66a9d0d4f4e304d58fad38c078d0336c445 (patch) | |
| tree | 184e21de28cb19106d700d4e2bd11a1a415ba034 /include/linux | |
| parent | 75df529bec9110dad43ab30e2d9490242529e8b8 (diff) | |
arm64: permit ACPI core to map kernel memory used for table overrides
Jonathan reports that the strict policy for memory mapped by the
ACPI core breaks the use case of passing ACPI table overrides via
initramfs. This is due to the fact that the memory type used for
loading the initramfs in memory is not recognized as a memory type
that is typically used by firmware to pass firmware tables.
Since the purpose of the strict policy is to ensure that no AML or
other ACPI code can manipulate any memory that is used by the kernel
to keep its internal state or the state of user tasks, we can relax
the permission check, and allow mappings of memory that is reserved
and marked as NOMAP via memblock, and therefore not covered by the
linear mapping to begin with.
Fixes: 1583052d111f ("arm64/acpi: disallow AML memory opregions to access kernel memory")
Fixes: 325f5585ec36 ("arm64/acpi: disallow writeable AML opregion mapping for EFI code regions")
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20200929132522.18067-1-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/acpi.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 1e4cdc6c7ae2..64ae25c59d55 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -958,7 +958,7 @@ void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state, acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b); -#ifdef CONFIG_X86 +#ifndef CONFIG_IA64 void arch_reserve_mem_area(acpi_physical_address addr, size_t size); #else static inline void arch_reserve_mem_area(acpi_physical_address addr, |