[PATCH] bpf: Fix bpf_seq_read docs for increased buffer size

[PATCH] bpf: Fix bpf_seq_read docs for increased buffer size

[T.J. Mercier]

Commit af65320948b8 ("bpf: Bump iter seq size to support BTF
representation of large data structures") increased the fixed buffer
size from PAGE_SIZE to PAGE_SIZE << 3, but the docs for the function
didn't get updated at the same time. Update them.

Fixes: af65320948b8 ("bpf: Bump iter seq size to support BTF representation of large data structures")
Signed-off-by: T.J. Mercier <tjmercier@google.com>
---
 kernel/bpf/bpf_iter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
index eec60b57bd3d..4b58d56ecab1 100644
--- a/kernel/bpf/bpf_iter.c
+++ b/kernel/bpf/bpf_iter.c
@@ -86,7 +86,7 @@ static bool bpf_iter_support_resched(struct seq_file *seq)
 
 /* bpf_seq_read, a customized and simpler version for bpf iterator.
  * The following are differences from seq_read():
- *  . fixed buffer size (PAGE_SIZE)
+ *  . fixed buffer size (PAGE_SIZE << 3)
  *  . assuming NULL ->llseek()
  *  . stop() may call bpf program, handling potential overflow there
  */
-- 
2.52.0.223.gf5cc29aaa4-goog

Re: [PATCH] bpf: Fix bpf_seq_read docs for increased buffer size

[Menglong Dong]

On 12/7/25 8:58 AM, T.J. Mercier wrote:
> Commit af65320948b8 ("bpf: Bump iter seq size to support BTF
> representation of large data structures") increased the fixed buffer
> size from PAGE_SIZE to PAGE_SIZE << 3, but the docs for the function
> didn't get updated at the same time. Update them.
> 
> Fixes: af65320948b8 ("bpf: Bump iter seq size to support BTF representation of large data structures")

I think we don't need the "Fixes" tag for the document fix?
Therefore, it's better to go to the "bpf-next" tree with the
corresponding tag:
  [PATCH bpf-next]

Thanks!
Menglong Dong

> Signed-off-by: T.J. Mercier <tjmercier@google.com>
> ---
>  kernel/bpf/bpf_iter.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
> index eec60b57bd3d..4b58d56ecab1 100644
> --- a/kernel/bpf/bpf_iter.c
> +++ b/kernel/bpf/bpf_iter.c
> @@ -86,7 +86,7 @@ static bool bpf_iter_support_resched(struct seq_file *seq)
>  
>  /* bpf_seq_read, a customized and simpler version for bpf iterator.
>   * The following are differences from seq_read():
> - *  . fixed buffer size (PAGE_SIZE)
> + *  . fixed buffer size (PAGE_SIZE << 3)
>   *  . assuming NULL ->llseek()
>   *  . stop() may call bpf program, handling potential overflow there
>   */
> 

Re: [PATCH] bpf: Fix bpf_seq_read docs for increased buffer size

[T.J. Mercier]

On Sun, Dec 7, 2025 at 2:08 PM Menglong Dong <menglong.dong@linux.dev> wrote:
>
> On 12/7/25 8:58 AM, T.J. Mercier wrote:
> > Commit af65320948b8 ("bpf: Bump iter seq size to support BTF
> > representation of large data structures") increased the fixed buffer
> > size from PAGE_SIZE to PAGE_SIZE << 3, but the docs for the function
> > didn't get updated at the same time. Update them.
> >
> > Fixes: af65320948b8 ("bpf: Bump iter seq size to support BTF representation of large data structures")
>
> I think we don't need the "Fixes" tag for the document fix?
> Therefore, it's better to go to the "bpf-next" tree with the
> corresponding tag:
>   [PATCH bpf-next]
>
> Thanks!
> Menglong Dong

SGTM, resent to bpf-next at:
https://lore.kernel.org/bpf/20251207091005.2829703-1-tjmercier@google.com/T/#u

Thanks!
-T.J.

> > Signed-off-by: T.J. Mercier <tjmercier@google.com>
> > ---
> >  kernel/bpf/bpf_iter.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
> > index eec60b57bd3d..4b58d56ecab1 100644
> > --- a/kernel/bpf/bpf_iter.c
> > +++ b/kernel/bpf/bpf_iter.c
> > @@ -86,7 +86,7 @@ static bool bpf_iter_support_resched(struct seq_file *seq)
> >
> >  /* bpf_seq_read, a customized and simpler version for bpf iterator.
> >   * The following are differences from seq_read():
> > - *  . fixed buffer size (PAGE_SIZE)
> > + *  . fixed buffer size (PAGE_SIZE << 3)
> >   *  . assuming NULL ->llseek()
> >   *  . stop() may call bpf program, handling potential overflow there
> >   */
> >
>
>
>
>