x86/bpf: Fix IP for relocating call depth accounting
The commit: 59bec00a ("x86/percpu: Introduce %rip-relative addressing to PER_CPU_VAR()") made PER_CPU_VAR() to use rip-relative addressing, hence INCREMENT_CALL_DEPTH macro and skl_call_thunk_template got rip-relative asm code inside of it. A follow up commit: 17bce3b2 ("x86/callthunks: Handle %rip-relative relocations in call thunk template") changed x86_call_depth_emit_accounting() to use apply_relocation(), but mistakenly assumed that the code is being patched in-place (where the destination of the relocation matches the address of the code), using *pprog as the destination ip. This is not true for the call depth accounting, emitted by the BPF JIT, so the calculated address was wrong, JIT-ed BPF progs on kernels with call depth tracking got broken and usually caused a page fault. Pass the destination IP when the BPF JIT emits call depth accounting. Fixes: 17bce3b2 ("x86/callthunks: Handle %rip-relative relocations in call thunk template") Signed-off-by: Joan Bruguera Micó <joanbrugueram@gmail.com> Reviewed-by: Uros Bizjak <ubizjak@gmail.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240401185821.224068-3-ubizjak@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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