Re: [PATCH v2 1/2] smb: client: let enum smb_eio_trace grow past 128 entries

[Namjae Jeon]

On Fri, Aug 21, 2026 at 11:25 AM Bryam Vargas via B4 Relay
<devnull+hexlabsecurity.proton.me@xxxxxxxxxx> wrote:
>
> From: Bryam Vargas <hexlabsecurity@xxxxxxxxx>
>
> enum smb_eio_trace is __mode(byte) and the list has held exactly 128
> entries since it was added, so the last sits at index 127 and a 129th has
> no representable value.  clang gives the enum a signed underlying type and
> converts the overflowing value to -128; x86_64 defconfig turns that into a
> build failure because it sets CONFIG_WERROR=y, and where it does not, the
> value stops matching the __print_symbolic() table and those events print a
> raw number.  gcc picks an unsigned underlying type and reports nothing.
>
> Drop the attribute.  On x86_64 the record does not grow: the field
> precedes an unsigned long at offset 8 of struct trace_event_raw_smb3_eio,
> so sizeof() stays 32 either way.
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202607290344.fvDmgRPA-lkp@xxxxxxxxx/
> Fixes: f80ac7eda1cf ("cifs: Add a tracepoint to log EIO errors")
> Cc: stable@xxxxxxxxxx
> Signed-off-by: Bryam Vargas <hexlabsecurity@xxxxxxxxx>
> ---
>  fs/smb/client/trace.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/smb/client/trace.h b/fs/smb/client/trace.h
> index 5b21ad3c15fb..0a91d3aaa079 100644
> --- a/fs/smb/client/trace.h
> +++ b/fs/smb/client/trace.h
> @@ -213,7 +213,7 @@
>  #define EM(a, b) a,
>  #define E_(a, b) a
>
> -enum smb_eio_trace             { smb_eio_traces } __mode(byte);
> +enum smb_eio_trace             { smb_eio_traces };
Looks ok. But these patches should be squashed because 0001 patch is
only required to make the new enum added by 0002 patch build
correctly.
Thanks.