6.17-stable review patch. If anyone has any objections, please let me know.
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From: Tao Chen chen.dylane@linux.dev
[ Upstream commit 4223bf833c8495e40ae2886acbc0ecbe88fa6306 ]
Now BPF program will run with migration disabled, so it is safe to access this_cpu_inc_return(bpf_bprintf_nest_level).
Fixes: d9c9e4db186a ("bpf: Factorize bpf_trace_printk and bpf_seq_printf") Signed-off-by: Tao Chen chen.dylane@linux.dev Signed-off-by: Andrii Nakryiko andrii@kernel.org Link: https://lore.kernel.org/bpf/20250819125638.2544715-1-chen.dylane@linux.dev Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/helpers.c | 3 --- 1 file changed, 3 deletions(-)
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 8af62cb243d9e..9c750a6a895bf 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -774,11 +774,9 @@ int bpf_try_get_buffers(struct bpf_bprintf_buffers **bufs) { int nest_level;
- preempt_disable(); nest_level = this_cpu_inc_return(bpf_bprintf_nest_level); if (WARN_ON_ONCE(nest_level > MAX_BPRINTF_NEST_LEVEL)) { this_cpu_dec(bpf_bprintf_nest_level); - preempt_enable(); return -EBUSY; } *bufs = this_cpu_ptr(&bpf_bprintf_bufs[nest_level - 1]); @@ -791,7 +789,6 @@ void bpf_put_buffers(void) if (WARN_ON_ONCE(this_cpu_read(bpf_bprintf_nest_level) == 0)) return; this_cpu_dec(bpf_bprintf_nest_level); - preempt_enable(); }
void bpf_bprintf_cleanup(struct bpf_bprintf_data *data)