| Message ID | Z-bFsmWjr5yZy6c6@kspp (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,next] drm/nouveau/outp: Avoid -Wflex-array-member-not-at-end warning | expand |
On Fri, Mar 28, 2025 at 09:52:18AM -0600, Gustavo A. R. Silva wrote: > -Wflex-array-member-not-at-end was introduced in GCC-14, and we are > getting ready to enable it, globally. > > Use the `DEFINE_RAW_FLEX()` helper for an on-stack definition of > a flexible structure where the size of the flexible-array member > is known at compile-time, and refactor the rest of the code, > accordingly. > > So, with these changes, fix the following warning: > > drivers/gpu/drm/nouveau/nvif/outp.c:199:45: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > --- > Changes in v2: > - Avoid using magic number in if statement. (Danilo) > - Use sizeof() instead of __struct_size(). Good catch -- I guess the original code should have been a bit more obvious by passing &args.mthd, rather than &args. Applied to drm-misc-next, thanks!
diff --git a/drivers/gpu/drm/nouveau/nvif/outp.c b/drivers/gpu/drm/nouveau/nvif/outp.c index 6daeb7f0b09b..1ea20b2bdd29 100644 --- a/drivers/gpu/drm/nouveau/nvif/outp.c +++ b/drivers/gpu/drm/nouveau/nvif/outp.c @@ -195,20 +195,17 @@ nvif_outp_dp_aux_pwr(struct nvif_outp *outp, bool enable) int nvif_outp_hda_eld(struct nvif_outp *outp, int head, void *data, u32 size) { - struct { - struct nvif_outp_hda_eld_v0 mthd; - u8 data[128]; - } args; + DEFINE_RAW_FLEX(struct nvif_outp_hda_eld_v0, mthd, data, 128); int ret; - if (WARN_ON(size > ARRAY_SIZE(args.data))) + if (WARN_ON(size > (__struct_size(mthd) - sizeof(*mthd)))) return -EINVAL; - args.mthd.version = 0; - args.mthd.head = head; + mthd->version = 0; + mthd->head = head; - memcpy(args.data, data, size); - ret = nvif_mthd(&outp->object, NVIF_OUTP_V0_HDA_ELD, &args, sizeof(args.mthd) + size); + memcpy(mthd->data, data, size); + ret = nvif_mthd(&outp->object, NVIF_OUTP_V0_HDA_ELD, mthd, sizeof(*mthd) + size); NVIF_ERRON(ret, &outp->object, "[HDA_ELD head:%d size:%d]", head, size); return ret; }
-Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Use the `DEFINE_RAW_FLEX()` helper for an on-stack definition of a flexible structure where the size of the flexible-array member is known at compile-time, and refactor the rest of the code, accordingly. So, with these changes, fix the following warning: drivers/gpu/drm/nouveau/nvif/outp.c:199:45: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- Changes in v2: - Avoid using magic number in if statement. (Danilo) - Use sizeof() instead of __struct_size(). v1: - Link: https://lore.kernel.org/linux-hardening/Z-a2DAQmcsHHlyci@kspp/ drivers/gpu/drm/nouveau/nvif/outp.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)