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    Subject[PATCH v7 04/11] scs: disable when function graph tracing is enabled
    From
    The graph tracer hooks returns by modifying frame records on the
    (regular) stack, but with SCS the return address is taken from the
    shadow stack, and the value in the frame record has no effect. As we
    don't currently have a mechanism to determine the corresponding slot
    on the shadow stack (and to pass this through the ftrace
    infrastructure), for now let's disable SCS when the graph tracer is
    enabled.

    Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
    ---
    arch/Kconfig | 1 +
    1 file changed, 1 insertion(+)

    diff --git a/arch/Kconfig b/arch/Kconfig
    index 1b16aa9a3fe5..0d746373c52e 100644
    --- a/arch/Kconfig
    +++ b/arch/Kconfig
    @@ -530,6 +530,7 @@ config ARCH_SUPPORTS_SHADOW_CALL_STACK

    config SHADOW_CALL_STACK
    bool "Clang Shadow Call Stack"
    + depends on !FUNCTION_GRAPH_TRACER
    depends on ARCH_SUPPORTS_SHADOW_CALL_STACK
    help
    This option enables Clang's Shadow Call Stack, which uses a
    --
    2.25.0.341.g760bfbb309-goog
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