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-rw-r--r--drivers/firmware/efi/Kconfig57
1 files changed, 57 insertions, 0 deletions
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index d4ea929e8b34..ecc83e2f032c 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -75,6 +75,27 @@ config EFI_MAX_FAKE_MEM
Ranges can be set up to this value using comma-separated list.
The default value is 8.
+config EFI_SOFT_RESERVE
+ bool "Reserve EFI Specific Purpose Memory"
+ depends on EFI && EFI_STUB && ACPI_HMAT
+ default ACPI_HMAT
+ help
+ On systems that have mixed performance classes of memory EFI
+ may indicate specific purpose memory with an attribute (See
+ EFI_MEMORY_SP in UEFI 2.8). A memory range tagged with this
+ attribute may have unique performance characteristics compared
+ to the system's general purpose "System RAM" pool. On the
+ expectation that such memory has application specific usage,
+ and its base EFI memory type is "conventional" answer Y to
+ arrange for the kernel to reserve it as a "Soft Reserved"
+ resource, and set aside for direct-access (device-dax) by
+ default. The memory range can later be optionally assigned to
+ the page allocator by system administrator policy via the
+ device-dax kmem facility. Say N to have the kernel treat this
+ memory as "System RAM" by default.
+
+ If unsure, say Y.
+
config EFI_PARAMS_FROM_FDT
bool
help
@@ -180,6 +201,42 @@ config RESET_ATTACK_MITIGATION
have been evicted, since otherwise it will trigger even on clean
reboots.
+config EFI_RCI2_TABLE
+ bool "EFI Runtime Configuration Interface Table Version 2 Support"
+ depends on X86 || COMPILE_TEST
+ help
+ Displays the content of the Runtime Configuration Interface
+ Table version 2 on Dell EMC PowerEdge systems as a binary
+ attribute 'rci2' under /sys/firmware/efi/tables directory.
+
+ RCI2 table contains BIOS HII in XML format and is used to populate
+ BIOS setup page in Dell EMC OpenManage Server Administrator tool.
+ The BIOS setup page contains BIOS tokens which can be configured.
+
+ Say Y here for Dell EMC PowerEdge systems.
+
+config EFI_DISABLE_PCI_DMA
+ bool "Clear Busmaster bit on PCI bridges during ExitBootServices()"
+ help
+ Disable the busmaster bit in the control register on all PCI bridges
+ while calling ExitBootServices() and passing control to the runtime
+ kernel. System firmware may configure the IOMMU to prevent malicious
+ PCI devices from being able to attack the OS via DMA. However, since
+ firmware can't guarantee that the OS is IOMMU-aware, it will tear
+ down IOMMU configuration when ExitBootServices() is called. This
+ leaves a window between where a hostile device could still cause
+ damage before Linux configures the IOMMU again.
+
+ If you say Y here, the EFI stub will clear the busmaster bit on all
+ PCI bridges before ExitBootServices() is called. This will prevent
+ any malicious PCI devices from being able to perform DMA until the
+ kernel reenables busmastering after configuring the IOMMU.
+
+ This option will cause failures with some poorly behaved hardware
+ and should not be enabled without testing. The kernel commandline
+ options "efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma"
+ may be used to override this option.
+
endmenu
config UEFI_CPER
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