[PATCH 6.1 0787/1146] ftrace: Allow WITH_ARGS flavour of graph tracer with shadow call stack

Greg Kroah-Hartman
2022-12-28T16:33:19Z

From: Ard Biesheuvel <ardb@kernel.org>

[ Upstream commit 38792972de4294163f44d6360fd221e6f2c22a05 ]

The recent switch on arm64 from DYNAMIC_FTRACE_WITH_REGS to
DYNAMIC_FTRACE_WITH_ARGS failed to take into account that we currently
require the former in order to allow the function graph tracer to be
enabled in combination with shadow call stacks. This means that this is
no longer permitted at all, in spite of the fact that either flavour of
ftrace works perfectly fine in this combination.

So permit WITH_ARGS as well as WITH_REGS.

Fixes: ddc9863e9e90 ("scs: Disable when function graph tracing is enabled")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20221213132407.1485025-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index 8f138e580d1a..81599f5c17b0 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -635,7 +635,7 @@ config ARCH_SUPPORTS_SHADOW_CALL_STACK
config SHADOW_CALL_STACK
bool "Shadow Call Stack"
depends on ARCH_SUPPORTS_SHADOW_CALL_STACK
- depends on DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER
+ depends on DYNAMIC_FTRACE_WITH_ARGS || DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER
help
This option enables the compiler's Shadow Call Stack, which
uses a shadow stack to protect function return addresses from
--
2.35.1