| Message ID | 20230720103107.817084-1-contact@emersion.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/ioctl: turn on -Woverride-init for IOCTL table | expand |
On Thu, 20 Jul 2023, Simon Ser <contact@emersion.fr> wrote: > Recently two patches [1] [2] have hit a case of mistakenly picking > an IOCTL number which was already in-use. This is hard to debug > because the last definition wins and there is no indication that > there is a conflict. > > Fix this by enabling -Werror=override-init for the IOCTL table. > When there is a duplicate entry, the compiler now errors out: > > CC [M] drivers/gpu/drm/drm_ioctl.o > drivers/gpu/drm/drm_ioctl.c:555:33: error: initialized field overwritten [-Werror=override-init] > 555 | [DRM_IOCTL_NR(ioctl)] = { \ > | ^ > drivers/gpu/drm/drm_ioctl.c:708:9: note: in expansion of macro ‘DRM_IOCTL_DEF’ > 708 | DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_reset_ioctl, > | ^~~~~~~~~~~~~ > drivers/gpu/drm/drm_ioctl.c:555:33: note: (near initialization for ‘drm_ioctls[207]’) > 555 | [DRM_IOCTL_NR(ioctl)] = { \ > | ^ > drivers/gpu/drm/drm_ioctl.c:708:9: note: in expansion of macro ‘DRM_IOCTL_DEF’ > 708 | DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_reset_ioctl, > | ^~~~~~~~~~~~~ > cc1: some warnings being treated as errors > > [1]: https://lore.kernel.org/dri-devel/20230714111257.11940-1-contact@emersion.fr/ > [2]: https://lore.kernel.org/dri-devel/vVFDBgHpdcB0vOwnl02QPOFmAZPEbIV56E_wQ8B012K2GZ-fAGyG0JMbSrMu3-IcKYVf0JpJyrf71e6KFHfeMoSPJlYRACxlxy91eW9c6Fc=@emersion.fr/ > > Signed-off-by: Simon Ser <contact@emersion.fr> > Cc: Erik Kurzinger <ekurzinger@nvidia.com> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: Thomas Zimmermann <tzimmermann@suse.de> > Cc: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/drm_ioctl.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c > index f03ffbacfe9b..cd485eb54d2a 100644 > --- a/drivers/gpu/drm/drm_ioctl.c > +++ b/drivers/gpu/drm/drm_ioctl.c > @@ -566,6 +566,8 @@ static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) > #endif > > /* Ioctl table */ > +#pragma GCC diagnostic push > +#pragma GCC diagnostic error "-Woverride-init" You should probably use __diag_push(), __diag_warn(), and __diag_pop() compiler agnostic wrappers instead of using #pragmas directly. BR, Jani. > static const struct drm_ioctl_desc drm_ioctls[] = { > DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW), > DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), > @@ -718,6 +720,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = { > DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER), > }; > +#pragma GCC diagnostic pop > > #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index f03ffbacfe9b..cd485eb54d2a 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -566,6 +566,8 @@ static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv) #endif /* Ioctl table */ +#pragma GCC diagnostic push +#pragma GCC diagnostic error "-Woverride-init" static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0), @@ -718,6 +720,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER), }; +#pragma GCC diagnostic pop #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
Recently two patches [1] [2] have hit a case of mistakenly picking an IOCTL number which was already in-use. This is hard to debug because the last definition wins and there is no indication that there is a conflict. Fix this by enabling -Werror=override-init for the IOCTL table. When there is a duplicate entry, the compiler now errors out: CC [M] drivers/gpu/drm/drm_ioctl.o drivers/gpu/drm/drm_ioctl.c:555:33: error: initialized field overwritten [-Werror=override-init] 555 | [DRM_IOCTL_NR(ioctl)] = { \ | ^ drivers/gpu/drm/drm_ioctl.c:708:9: note: in expansion of macro ‘DRM_IOCTL_DEF’ 708 | DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_reset_ioctl, | ^~~~~~~~~~~~~ drivers/gpu/drm/drm_ioctl.c:555:33: note: (near initialization for ‘drm_ioctls[207]’) 555 | [DRM_IOCTL_NR(ioctl)] = { \ | ^ drivers/gpu/drm/drm_ioctl.c:708:9: note: in expansion of macro ‘DRM_IOCTL_DEF’ 708 | DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_reset_ioctl, | ^~~~~~~~~~~~~ cc1: some warnings being treated as errors [1]: https://lore.kernel.org/dri-devel/20230714111257.11940-1-contact@emersion.fr/ [2]: https://lore.kernel.org/dri-devel/vVFDBgHpdcB0vOwnl02QPOFmAZPEbIV56E_wQ8B012K2GZ-fAGyG0JMbSrMu3-IcKYVf0JpJyrf71e6KFHfeMoSPJlYRACxlxy91eW9c6Fc=@emersion.fr/ Signed-off-by: Simon Ser <contact@emersion.fr> Cc: Erik Kurzinger <ekurzinger@nvidia.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Christian König <christian.koenig@amd.com> --- drivers/gpu/drm/drm_ioctl.c | 3 +++ 1 file changed, 3 insertions(+)