On Thu, 24 Aug 2023, Thierry Reding <thierry.red...@gmail.com> wrote: > On Thu, Aug 24, 2023 at 08:37:00AM +0100, Lee Jones wrote: >> When converting from int to string, we must allow for up to 10-chars >> (2147483647). >> >> Fixes the following W=1 kernel build warning(s): >> >> drivers/gpu/drm/tegra/hub.c: In function ‘tegra_display_hub_probe’: >> drivers/gpu/drm/tegra/hub.c:1106:47: warning: ‘%u’ directive output may be >> truncated writing between 1 and 10 bytes into a region of size 4 >> [-Wformat-truncation=] >> drivers/gpu/drm/tegra/hub.c:1106:42: note: directive argument in the range >> [0, 4294967294] >> drivers/gpu/drm/tegra/hub.c:1106:17: note: ‘snprintf’ output between 6 and >> 15 bytes into a destination of size 8 > > I wish there was (perhaps there is?) a better way to annotate that i > will always be within a given range. In practice this is always going to > be smaller than 10 and even in future hardware I wouldn't expect this to > ever exceed anything like 32 or 64, so 8 characters is already generous.
I assume you could do snprintf(id, sizeof(id), "wgrp%u", (unsigned char)i); but it's perhaps less obvious than just increasing the size of the buffer. BR, Jani. > > Thierry > >> >> Signed-off-by: Lee Jones <l...@kernel.org> >> --- >> Cc: Thierry Reding <thierry.red...@gmail.com> >> Cc: Mikko Perttunen <mperttu...@nvidia.com> >> Cc: David Airlie <airl...@gmail.com> >> Cc: Daniel Vetter <dan...@ffwll.ch> >> Cc: Jonathan Hunter <jonath...@nvidia.com> >> Cc: Philipp Zabel <p.za...@pengutronix.de> >> Cc: dri-devel@lists.freedesktop.org >> Cc: linux-te...@vger.kernel.org >> --- >> drivers/gpu/drm/tegra/hub.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/tegra/hub.c b/drivers/gpu/drm/tegra/hub.c >> index 1af5f8318d914..f21e57e8599ee 100644 >> --- a/drivers/gpu/drm/tegra/hub.c >> +++ b/drivers/gpu/drm/tegra/hub.c >> @@ -1101,7 +1101,7 @@ static int tegra_display_hub_probe(struct >> platform_device *pdev) >> >> for (i = 0; i < hub->soc->num_wgrps; i++) { >> struct tegra_windowgroup *wgrp = &hub->wgrps[i]; >> - char id[8]; >> + char id[16]; >> >> snprintf(id, sizeof(id), "wgrp%u", i); >> mutex_init(&wgrp->lock); >> -- >> 2.42.0.rc1.204.g551eb34607-goog >> -- Jani Nikula, Intel Open Source Graphics Center