[PATCH 39/50] ACPI: Fix possible alignment issues with GAS 'address' references
From: Len Brown <lenb@kernel.org>
Date: 2012-01-17 12:26:54
Also in:
linux-acpi, lkml
Subsystem:
acpi, the rest · Maintainers:
"Rafael J. Wysocki", Linus Torvalds
From: Myron Stowe <redacted> Generic Address Structures (GAS) may reside within ACPI tables which are byte aligned. This patch copies GAS 'address' references to a local variable, which will be naturally aligned, to be used going forward. ACPI Generic Address Structure (GAS) reference: ACPI Specification, Revision 4.0, Section 5.2.3.1, "Generic Address Structure" Signed-off-by: Myron Stowe <redacted> Signed-off-by: Len Brown <redacted> --- drivers/acpi/osl.c | 38 ++++++++++++++++++++++++-------------- 1 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index f31c5c5..2e285cd 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c@@ -166,17 +166,21 @@ static u32 acpi_osi_handler(acpi_string interface, u32 supported) return supported; } -static void __init acpi_request_region (struct acpi_generic_address *addr, +static void __init acpi_request_region (struct acpi_generic_address *gas, unsigned int length, char *desc) { - if (!addr->address || !length) + u64 addr; + + /* Handle possible alignment issues */ + memcpy(&addr, &gas->address, sizeof(addr)); + if (!addr || !length) return; /* Resources are never freed */ - if (addr->space_id == ACPI_ADR_SPACE_SYSTEM_IO) - request_region(addr->address, length, desc); - else if (addr->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) - request_mem_region(addr->address, length, desc); + if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO) + request_region(addr, length, desc); + else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) + request_mem_region(addr, length, desc); } static int __init acpi_reserve_resources(void)
@@ -427,35 +431,41 @@ void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size) __acpi_unmap_table(virt, size); } -static int acpi_os_map_generic_address(struct acpi_generic_address *addr) +static int acpi_os_map_generic_address(struct acpi_generic_address *gas) { + u64 addr; void __iomem *virt; - if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) + if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) return 0; - if (!addr->address || !addr->bit_width) + /* Handle possible alignment issues */ + memcpy(&addr, &gas->address, sizeof(addr)); + if (!addr || !gas->bit_width) return -EINVAL; - virt = acpi_os_map_memory(addr->address, addr->bit_width / 8); + virt = acpi_os_map_memory(addr, gas->bit_width / 8); if (!virt) return -EIO; return 0; } -static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) +static void acpi_os_unmap_generic_address(struct acpi_generic_address *gas) { + u64 addr; struct acpi_ioremap *map; - if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) + if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) return; - if (!addr->address || !addr->bit_width) + /* Handle possible alignment issues */ + memcpy(&addr, &gas->address, sizeof(addr)); + if (!addr || !gas->bit_width) return; mutex_lock(&acpi_ioremap_lock); - map = acpi_map_lookup(addr->address, addr->bit_width / 8); + map = acpi_map_lookup(addr, gas->bit_width / 8); if (!map) { mutex_unlock(&acpi_ioremap_lock); return;
--
1.7.9.rc1