Re: [PATCH bpf-next v7 11/22] bpf: Dispatch cleanup pads by rewriting return addresses

[Yonghong Song <yonghong.song@linux.dev>]

On 9/28/26 6:14 PM, bot+bpf-ci@kernel.org wrote:
>> diff --git a/kernel/bpf/fixups.c b/kernel/bpf/fixups.c
>> index 5b7fe4ba610b..bff9d2539371 100644
>> --- a/kernel/bpf/fixups.c
>> +++ b/kernel/bpf/fixups.c
>> @@ -1,5 +1,6 @@
>>   // SPDX-License-Identifier: GPL-2.0-only
>>   /* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */
>> +#include <linux/bitmap.h>
> This isn't a bug, but is <linux/bitmap.h> needed? No bitmap API appears
> in the file.

Thanks. Will remove.

> [ ... ]
>
>> @@ -1286,6 +1309,61 @@ static int resolve_func_ptrs(struct bpf_verifier_env *env)
>>   	return 0;
>>   }
>>
>> +static int exc_info_for_subprog(struct bpf_verifier_env *env, struct bpf_prog *sub,
>> +				u32 subprog, u32 start, u32 end)
>> +{
>> +	struct bpf_cleanup_info *recs;
>> +	u32 i, cnt = 0;
>> +	int err;
>> +
>> +	if (!env->cleanup_info_cnt)
>> +		return 0;
>> +
>> +	err = bpf_exc_alloc_info(sub->aux);
>> +	if (err)
>> +		return err;
>> +
>> +	for (i = start; i < end; i++) {
>> +		if (env->insn_aux_data[i].cleanup_pad)
>> +			cnt++;
>> +	}
>> +	if (!cnt)
>> +		return 0;
>> +
>> +	recs = kvmalloc_array(cnt, sizeof(*recs), GFP_KERNEL_ACCOUNT | __GFP_NOWARN);
>> +	if (!recs)
>> +		return -ENOMEM;
>> +
>> +	for (i = start, cnt = 0; i < end; i++) {
>> +		u32 pad = env->insn_aux_data[i].cleanup_pad;
>> +
>> +		if (!pad)
>> +			continue;
>> +		pad--;
>> +		if (verifier_bug_if(pad < start || pad >= end, env,
>> +				    "insn %u is covered by a landing pad at %u outside its subprog [%u, %u)",
>> +				    i, pad, start, end)) {
>> +			kvfree(recs);
>> +			return -EFAULT;
>> +		}
>> +		recs[cnt].begin_off = i - start;
>> +		recs[cnt].end_off = i - start + 1;
>> +		recs[cnt].landing_pad_off = pad - start;
>> +		cnt++;
>> +	}
>> +	err = bpf_exc_attach_info(sub->aux, recs, cnt);
>> +	if (err)
>> +		return err;
>> +	return 0;
>> +}
> This isn't a bug, but is the subprog parameter meant to be used? The
> function body uses only start and end, yet both callers pass a value for
> it.

Will remove unused 'subprog' parameter.