diff options
| author | Kees Cook <keescook@chromium.org> | 2017-07-17 15:05:11 -0700 |
|---|---|---|
| committer | Rob Herring <robh@kernel.org> | 2017-07-24 12:49:56 -0500 |
| commit | e5bc0c37c97e1edb4ef491fc8d50d7ca7ffdaadb (patch) | |
| tree | 4fcce8d7413bbd0d984db2ba4285cd8cf58a94f2 /Documentation/devicetree/bindings/chosen.txt | |
| parent | e2af1f561168897de43b179e5b9d513392721eff (diff) | |
dt-bindings: chosen: document kaslr-seed property
Document the /chosen/kaslr-seed property (and its interaction with the
EFI_RNG_PROTOCOL API). Thanks to Ard for clarifications.
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'Documentation/devicetree/bindings/chosen.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/chosen.txt | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index dee3f5d9df26..e3b13ea7d2ae 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -5,9 +5,31 @@ The chosen node does not represent a real device, but serves as a place for passing data between firmware and the operating system, like boot arguments. Data in the chosen node does not represent the hardware. +The following properties are recognized: -stdout-path property --------------------- + +kaslr-seed +----------- + +This property is used when booting with CONFIG_RANDOMIZE_BASE as the +entropy used to randomize the kernel image base address location. Since +it is used directly, this value is intended only for KASLR, and should +not be used for other purposes (as it may leak information about KASLR +offsets). It is parsed as a u64 value, e.g. + +/ { + chosen { + kaslr-seed = <0xfeedbeef 0xc0def00d>; + }; +}; + +Note that if this property is set from UEFI (or a bootloader in EFI +mode) when EFI_RNG_PROTOCOL is supported, it will be overwritten by +the Linux EFI stub (which will populate the property itself, using +EFI_RNG_PROTOCOL). + +stdout-path +----------- Device trees may specify the device to be used for boot console output with a stdout-path property under /chosen, as described in the Devicetree |