Re: [PATCH] nvme-tcp: replace sg_init_marker() with sg_init_table()

[Chaitanya Kulkarni]

On 10/22/22 10:46, Nam Cao wrote:
> In nvme_tcp_ddgst_update(), sg_init_marker() is called with an
> uninitialized scatterlist. This is probably fine, but gcc complains:
> 
>    CC [M]  drivers/nvme/host/tcp.o
> In file included from ./include/linux/dma-mapping.h:10,
>                   from ./include/linux/skbuff.h:31,
>                   from ./include/net/net_namespace.h:43,
>                   from ./include/linux/netdevice.h:38,
>                   from ./include/net/sock.h:46,
>                   from drivers/nvme/host/tcp.c:12:
> In function ‘sg_mark_end’,
>      inlined from ‘sg_init_marker’ at ./include/linux/scatterlist.h:356:2,
>      inlined from ‘nvme_tcp_ddgst_update’ at drivers/nvme/host/tcp.c:390:2:
> ./include/linux/scatterlist.h:234:11: error: ‘sg.page_link’ is used uninitialized [-Werror=uninitialized]
>    234 |         sg->page_link |= SG_END;
>        |         ~~^~~~~~~~~~~
> drivers/nvme/host/tcp.c: In function ‘nvme_tcp_ddgst_update’:
> drivers/nvme/host/tcp.c:388:28: note: ‘sg’ declared here
>    388 |         struct scatterlist sg;
>        |                            ^~
> cc1: all warnings being treated as errors
> 
> Use sg_init_table() instead, which basically memset the scatterlist to
> zero first before calling sg_init_marker().
> 
> Signed-off-by: Nam Cao <namcaov@xxxxxxxxx>

Looks good to me, can you please share what version if gcc you are
using ? my test setup did not catch this error and I'd like to update
with the one that can catch these errors.

Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>

-ck