Commit 5bfdb4fb authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
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bpf: Disable exceptions when CONFIG_UNWINDER_FRAME_POINTER=y 



The build with CONFIG_UNWINDER_FRAME_POINTER=y is broken for
current exceptions feature as it assumes ORC unwinder specific fields in
the unwind_state. Disable exceptions when frame_pointer unwinder is
enabled for now.

Fixes: fd5d27b7 ("arch/x86: Implement arch_bpf_stack_walk")
Reported-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230918155233.297024-4-memxor@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 7d346063

arch/x86/net/bpf_jit_comp.c

+4 −5
Original line number Diff line number Diff line
@@ -3003,16 +3003,15 @@ void bpf_jit_free(struct bpf_prog *prog) 
bool bpf_jit_supports_exceptions(void)

{

	/* We unwind through both kernel frames (starting from within bpf_throw

	 * call) and BPF frames. Therefore we require one of ORC or FP unwinder

	 * to be enabled to walk kernel frames and reach BPF frames in the stack

	 * trace.

	 * call) and BPF frames. Therefore we require ORC unwinder to be enabled

	 * to walk kernel frames and reach BPF frames in the stack trace.

	 */

	return IS_ENABLED(CONFIG_UNWINDER_ORC) || IS_ENABLED(CONFIG_UNWINDER_FRAME_POINTER);

	return IS_ENABLED(CONFIG_UNWINDER_ORC);

}



void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie)

{

#if defined(CONFIG_UNWINDER_ORC) || defined(CONFIG_UNWINDER_FRAME_POINTER)

#if defined(CONFIG_UNWINDER_ORC)

	struct unwind_state state;

	unsigned long addr;