On Sat, Dec 16, 2023 at 01:54:56PM +0100, Christophe JAILLET wrote:
> When compiled with W=1, we get:
> block/blk-throttle.c: In function ‘tg_prfill_limit’:
> block/blk-throttle.c:1539:74: error: ‘snprintf’ output may be truncated before the last format character [-Werror=format-truncation=]
> 1539 | snprintf(idle_time, sizeof(idle_time), " idle=%lu",
> | ^
> block/blk-throttle.c:1539:25: note: ‘snprintf’ output between 8 and 27 bytes into a destination of size 26
> 1539 | snprintf(idle_time, sizeof(idle_time), " idle=%lu",
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 1540 | tg->idletime_threshold_conf);
> | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> block/blk-throttle.c:1546:43: error: ‘%lu’ directive output may be truncated writing between 1 and 20 bytes into a region of size 17 [-Werror=format-truncation=]
> 1546 | " latency=%lu", tg->latency_target_conf);
> | ^~~
> block/blk-throttle.c:1546:33: note: directive argument in the range [0, 18446744073709551614]
> 1546 | " latency=%lu", tg->latency_target_conf);
> | ^~~~~~~~~~~~~~
> block/blk-throttle.c:1545:25: note: ‘snprintf’ output between 11 and 30 bytes into a destination of size 26
> 1545 | snprintf(latency_time, sizeof(latency_time),
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 1546 | " latency=%lu", tg->latency_target_conf);
> | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> In order to fix it, remove all the intermediate buffers and write directly
> into the 'sf' seq_file.
>
> Fixes: ada75b6e5b2a ("blk-throttle: add interface to configure idle time threshold")
> Fixes: ec80991d6fc2 ("blk-throttle: add interface for per-cgroup target latency")
I'm not sure Fixes tags are necessary here given that this isn't something
we'd hit in practice.
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Looks fine to me, so:
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
But, can you please briefly explain how you tested the patch?
Thanks.
--
tejun
