6.6-stable review patch. If anyone has any objections, please let me know.
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From: Andy Chiu andy.chiu@sifive.com
[ Upstream commit 23b2188920a25e88d447dd7d819a0b0f62fb4455 ]
arch_stack_walk() is called intensively in function_graph when the kernel is compiled with CONFIG_TRACE_IRQFLAGS. As a result, the kernel logs a lot of arch_stack_walk and its sub-functions into the ftrace buffer. However, these functions should not appear on the trace log because they are part of the ftrace itself. This patch references what arm64 does for the smae function. So it further prevent the re-enter kprobe issue, which is also possible on riscv.
Related-to: commit 0fbcd8abf337 ("arm64: Prohibit instrumentation on arch_stack_walk()") Fixes: 680341382da5 ("riscv: add CALLER_ADDRx support") Signed-off-by: Andy Chiu andy.chiu@sifive.com Reviewed-by: Alexandre Ghiti alexghiti@rivosinc.com Link: https://lore.kernel.org/r/20240613-dev-andyc-dyn-ftrace-v4-v1-1-1a538e12c01e... Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/kernel/stacktrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index 528ec7cc9a622..0d3f00eb0baee 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -156,7 +156,7 @@ unsigned long __get_wchan(struct task_struct *task) return pc; }
-noinline void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, +noinline noinstr void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, struct task_struct *task, struct pt_regs *regs) { walk_stackframe(task, regs, consume_entry, cookie);