Gustavo A. R. Silva
2025-Apr-03 16:45 UTC
[PATCH][next] drm/nouveau: chan: Avoid -Wflex-array-member-not-at-end warnings
-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 a few on-stack definitions 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 warnings: drivers/gpu/drm/nouveau/nouveau_chan.c:274:37: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/gpu/drm/nouveau/nouveau_chan.c:371:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/gpu/drm/nouveau/nouveau_chan.c:524:42: 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 at kernel.org> --- drivers/gpu/drm/nouveau/nouveau_chan.c | 115 ++++++++++++------------- 1 file changed, 56 insertions(+), 59 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.c b/drivers/gpu/drm/nouveau/nouveau_chan.c index cd659b9fd1d9..a7e70517b7cd 100644 --- a/drivers/gpu/drm/nouveau/nouveau_chan.c +++ b/drivers/gpu/drm/nouveau/nouveau_chan.c @@ -270,10 +270,7 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, { NV03_CHANNEL_DMA , 0 }, {} }; - struct { - struct nvif_chan_v0 chan; - char name[TASK_COMM_LEN+16]; - } args; + DEFINE_RAW_FLEX(struct nvif_chan_v0, args, name, TASK_COMM_LEN + 16); struct nvif_device *device = &cli->device; struct nouveau_channel *chan; const u64 plength = 0x10000; @@ -298,28 +295,28 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, return ret; /* create channel object */ - args.chan.version = 0; - args.chan.namelen = sizeof(args.name); - args.chan.runlist = __ffs64(runm); - args.chan.runq = 0; - args.chan.priv = priv; - args.chan.devm = BIT(0); + args->version = 0; + args->namelen = __struct_size(args) - sizeof(*args); + args->runlist = __ffs64(runm); + args->runq = 0; + args->priv = priv; + args->devm = BIT(0); if (hosts[cid].oclass < NV50_CHANNEL_GPFIFO) { - args.chan.vmm = 0; - args.chan.ctxdma = nvif_handle(&chan->push.ctxdma); - args.chan.offset = chan->push.addr; - args.chan.length = 0; + args->vmm = 0; + args->ctxdma = nvif_handle(&chan->push.ctxdma); + args->offset = chan->push.addr; + args->length = 0; } else { - args.chan.vmm = nvif_handle(&chan->vmm->vmm.object); + args->vmm = nvif_handle(&chan->vmm->vmm.object); if (hosts[cid].oclass < FERMI_CHANNEL_GPFIFO) - args.chan.ctxdma = nvif_handle(&chan->push.ctxdma); + args->ctxdma = nvif_handle(&chan->push.ctxdma); else - args.chan.ctxdma = 0; - args.chan.offset = ioffset + chan->push.addr; - args.chan.length = ilength; + args->ctxdma = 0; + args->offset = ioffset + chan->push.addr; + args->length = ilength; } - args.chan.huserd = 0; - args.chan.ouserd = 0; + args->huserd = 0; + args->ouserd = 0; /* allocate userd */ if (hosts[cid].oclass >= VOLTA_CHANNEL_GPFIFO_A) { @@ -329,27 +326,28 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, if (ret) return ret; - args.chan.huserd = nvif_handle(&chan->mem_userd.object); - args.chan.ouserd = 0; + args->huserd = nvif_handle(&chan->mem_userd.object); + args->ouserd = 0; chan->userd = &chan->mem_userd.object; } else { chan->userd = &chan->user; } - snprintf(args.name, sizeof(args.name), "%s[%d]", current->comm, task_pid_nr(current)); + snprintf(args->name, __struct_size(args) - sizeof(*args), "%s[%d]", + current->comm, task_pid_nr(current)); ret = nvif_object_ctor(&device->object, "abi16ChanUser", 0, hosts[cid].oclass, - &args, sizeof(args), &chan->user); + args, __struct_size(args), &chan->user); if (ret) { nouveau_channel_del(pchan); return ret; } - chan->runlist = args.chan.runlist; - chan->chid = args.chan.chid; - chan->inst = args.chan.inst; - chan->token = args.chan.token; + chan->runlist = args->runlist; + chan->chid = args->chid; + chan->inst = args->inst; + chan->token = args->token; return 0; } @@ -367,17 +365,17 @@ nouveau_channel_init(struct nouveau_channel *chan, u32 vram, u32 gart) return ret; if (chan->user.oclass >= FERMI_CHANNEL_GPFIFO) { - struct { - struct nvif_event_v0 base; - struct nvif_chan_event_v0 host; - } args; + DEFINE_RAW_FLEX(struct nvif_event_v0, args, data, + sizeof(struct nvif_chan_event_v0)); + struct nvif_chan_event_v0 *host + (struct nvif_chan_event_v0 *)args->data; - args.host.version = 0; - args.host.type = NVIF_CHAN_EVENT_V0_KILLED; + host->version = 0; + host->type = NVIF_CHAN_EVENT_V0_KILLED; ret = nvif_event_ctor(&chan->user, "abi16ChanKilled", chan->chid, nouveau_channel_killed, false, - &args.base, sizeof(args), &chan->kill); + args, __struct_size(args), &chan->kill); if (ret == 0) ret = nvif_event_allow(&chan->kill); if (ret) { @@ -520,46 +518,45 @@ nouveau_channels_fini(struct nouveau_drm *drm) int nouveau_channels_init(struct nouveau_drm *drm) { - struct { - struct nv_device_info_v1 m; - struct { - struct nv_device_info_v1_data channels; - struct nv_device_info_v1_data runlists; - } v; - } args = { - .m.version = 1, - .m.count = sizeof(args.v) / sizeof(args.v.channels), - .v.channels.mthd = NV_DEVICE_HOST_CHANNELS, - .v.runlists.mthd = NV_DEVICE_HOST_RUNLISTS, - }; + DEFINE_RAW_FLEX(struct nv_device_info_v1, args, data, 2); + struct nv_device_info_v1_data *channels = &args->data[0]; + struct nv_device_info_v1_data *runlists = &args->data[1]; struct nvif_object *device = &drm->client.device.object; int ret, i; - ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, &args, sizeof(args)); + args->version = 1; + args->count = (__struct_size(args) - sizeof(*args)) / + sizeof(*args->data); + channels->mthd = NV_DEVICE_HOST_CHANNELS; + runlists->mthd = NV_DEVICE_HOST_RUNLISTS; + + ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, args, + __struct_size(args)); if (ret || - args.v.runlists.mthd == NV_DEVICE_INFO_INVALID || !args.v.runlists.data || - args.v.channels.mthd == NV_DEVICE_INFO_INVALID) + runlists->mthd == NV_DEVICE_INFO_INVALID || !runlists->data || + channels->mthd == NV_DEVICE_INFO_INVALID) return -ENODEV; - drm->chan_nr = drm->chan_total = args.v.channels.data; - drm->runl_nr = fls64(args.v.runlists.data); + drm->chan_nr = drm->chan_total = channels->data; + drm->runl_nr = fls64(runlists->data); drm->runl = kcalloc(drm->runl_nr, sizeof(*drm->runl), GFP_KERNEL); if (!drm->runl) return -ENOMEM; if (drm->chan_nr == 0) { for (i = 0; i < drm->runl_nr; i++) { - if (!(args.v.runlists.data & BIT(i))) + if (!(runlists->data & BIT(i))) continue; - args.v.channels.mthd = NV_DEVICE_HOST_RUNLIST_CHANNELS; - args.v.channels.data = i; + channels->mthd = NV_DEVICE_HOST_RUNLIST_CHANNELS; + channels->data = i; - ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, &args, sizeof(args)); - if (ret || args.v.channels.mthd == NV_DEVICE_INFO_INVALID) + ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, args, + __struct_size(args)); + if (ret || channels->mthd == NV_DEVICE_INFO_INVALID) return -ENODEV; - drm->runl[i].chan_nr = args.v.channels.data; + drm->runl[i].chan_nr = channels->data; drm->runl[i].chan_id_base = drm->chan_total; drm->runl[i].context_base = dma_fence_context_alloc(drm->runl[i].chan_nr); -- 2.43.0
Kees Cook
2025-Apr-07 19:50 UTC
[PATCH][next] drm/nouveau: chan: Avoid -Wflex-array-member-not-at-end warnings
On Thu, Apr 03, 2025 at 10:45:18AM -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 a few on-stack definitions > 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 warnings: > > drivers/gpu/drm/nouveau/nouveau_chan.c:274:37: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > drivers/gpu/drm/nouveau/nouveau_chan.c:371:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] > drivers/gpu/drm/nouveau/nouveau_chan.c:524:42: 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 at kernel.org> > --- > drivers/gpu/drm/nouveau/nouveau_chan.c | 115 ++++++++++++------------- > 1 file changed, 56 insertions(+), 59 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.c b/drivers/gpu/drm/nouveau/nouveau_chan.c > index cd659b9fd1d9..a7e70517b7cd 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_chan.c > +++ b/drivers/gpu/drm/nouveau/nouveau_chan.c > @@ -270,10 +270,7 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, > { NV03_CHANNEL_DMA , 0 }, > {} > }; > - struct { > - struct nvif_chan_v0 chan; > - char name[TASK_COMM_LEN+16]; > - } args; > + DEFINE_RAW_FLEX(struct nvif_chan_v0, args, name, TASK_COMM_LEN + 16); > struct nvif_device *device = &cli->device; > struct nouveau_channel *chan; > const u64 plength = 0x10000; > @@ -298,28 +295,28 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, > return ret; > > /* create channel object */ > - args.chan.version = 0; > - args.chan.namelen = sizeof(args.name); > - args.chan.runlist = __ffs64(runm); > - args.chan.runq = 0; > - args.chan.priv = priv; > - args.chan.devm = BIT(0); > + args->version = 0; > + args->namelen = __struct_size(args) - sizeof(*args);Does __struct_size(args->name) work here (and later)?> + args->runlist = __ffs64(runm); > + args->runq = 0; > + args->priv = priv; > + args->devm = BIT(0); > if (hosts[cid].oclass < NV50_CHANNEL_GPFIFO) { > - args.chan.vmm = 0; > - args.chan.ctxdma = nvif_handle(&chan->push.ctxdma); > - args.chan.offset = chan->push.addr; > - args.chan.length = 0; > + args->vmm = 0; > + args->ctxdma = nvif_handle(&chan->push.ctxdma); > + args->offset = chan->push.addr; > + args->length = 0; > } else { > - args.chan.vmm = nvif_handle(&chan->vmm->vmm.object); > + args->vmm = nvif_handle(&chan->vmm->vmm.object); > if (hosts[cid].oclass < FERMI_CHANNEL_GPFIFO) > - args.chan.ctxdma = nvif_handle(&chan->push.ctxdma); > + args->ctxdma = nvif_handle(&chan->push.ctxdma); > else > - args.chan.ctxdma = 0; > - args.chan.offset = ioffset + chan->push.addr; > - args.chan.length = ilength; > + args->ctxdma = 0; > + args->offset = ioffset + chan->push.addr; > + args->length = ilength; > } > - args.chan.huserd = 0; > - args.chan.ouserd = 0; > + args->huserd = 0; > + args->ouserd = 0; > > /* allocate userd */ > if (hosts[cid].oclass >= VOLTA_CHANNEL_GPFIFO_A) { > @@ -329,27 +326,28 @@ nouveau_channel_ctor(struct nouveau_cli *cli, bool priv, u64 runm, > if (ret) > return ret; > > - args.chan.huserd = nvif_handle(&chan->mem_userd.object); > - args.chan.ouserd = 0; > + args->huserd = nvif_handle(&chan->mem_userd.object); > + args->ouserd = 0; > > chan->userd = &chan->mem_userd.object; > } else { > chan->userd = &chan->user; > } > > - snprintf(args.name, sizeof(args.name), "%s[%d]", current->comm, task_pid_nr(current)); > + snprintf(args->name, __struct_size(args) - sizeof(*args), "%s[%d]", > + current->comm, task_pid_nr(current)); > > ret = nvif_object_ctor(&device->object, "abi16ChanUser", 0, hosts[cid].oclass, > - &args, sizeof(args), &chan->user); > + args, __struct_size(args), &chan->user); > if (ret) { > nouveau_channel_del(pchan); > return ret; > } > > - chan->runlist = args.chan.runlist; > - chan->chid = args.chan.chid; > - chan->inst = args.chan.inst; > - chan->token = args.chan.token; > + chan->runlist = args->runlist; > + chan->chid = args->chid; > + chan->inst = args->inst; > + chan->token = args->token; > return 0; > } > > @@ -367,17 +365,17 @@ nouveau_channel_init(struct nouveau_channel *chan, u32 vram, u32 gart) > return ret; > > if (chan->user.oclass >= FERMI_CHANNEL_GPFIFO) { > - struct { > - struct nvif_event_v0 base; > - struct nvif_chan_event_v0 host; > - } args; > + DEFINE_RAW_FLEX(struct nvif_event_v0, args, data, > + sizeof(struct nvif_chan_event_v0)); > + struct nvif_chan_event_v0 *host > + (struct nvif_chan_event_v0 *)args->data; > > - args.host.version = 0; > - args.host.type = NVIF_CHAN_EVENT_V0_KILLED; > + host->version = 0; > + host->type = NVIF_CHAN_EVENT_V0_KILLED; > > ret = nvif_event_ctor(&chan->user, "abi16ChanKilled", chan->chid, > nouveau_channel_killed, false, > - &args.base, sizeof(args), &chan->kill); > + args, __struct_size(args), &chan->kill); > if (ret == 0) > ret = nvif_event_allow(&chan->kill); > if (ret) { > @@ -520,46 +518,45 @@ nouveau_channels_fini(struct nouveau_drm *drm) > int > nouveau_channels_init(struct nouveau_drm *drm) > { > - struct { > - struct nv_device_info_v1 m; > - struct { > - struct nv_device_info_v1_data channels; > - struct nv_device_info_v1_data runlists; > - } v; > - } args = { > - .m.version = 1, > - .m.count = sizeof(args.v) / sizeof(args.v.channels),sizeof(args.v) == sizeof(struct nv_device_info_v1_data) * 2 and sizeof(args.v.channels) == sizeof(struct nv_device_info_v1_data). Isn't this just "2"? i.e. isn't struct nv_device_info_v1::count the counted_by for struct nv_device_info_v1::data?> - .v.channels.mthd = NV_DEVICE_HOST_CHANNELS, > - .v.runlists.mthd = NV_DEVICE_HOST_RUNLISTS, > - }; > + DEFINE_RAW_FLEX(struct nv_device_info_v1, args, data, 2); > + struct nv_device_info_v1_data *channels = &args->data[0]; > + struct nv_device_info_v1_data *runlists = &args->data[1]; > struct nvif_object *device = &drm->client.device.object; > int ret, i; > > - ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, &args, sizeof(args)); > + args->version = 1; > + args->count = (__struct_size(args) - sizeof(*args)) / > + sizeof(*args->data); > + channels->mthd = NV_DEVICE_HOST_CHANNELS; > + runlists->mthd = NV_DEVICE_HOST_RUNLISTS; > + > + ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, args, > + __struct_size(args)); > if (ret || > - args.v.runlists.mthd == NV_DEVICE_INFO_INVALID || !args.v.runlists.data || > - args.v.channels.mthd == NV_DEVICE_INFO_INVALID) > + runlists->mthd == NV_DEVICE_INFO_INVALID || !runlists->data || > + channels->mthd == NV_DEVICE_INFO_INVALID) > return -ENODEV; > > - drm->chan_nr = drm->chan_total = args.v.channels.data; > - drm->runl_nr = fls64(args.v.runlists.data); > + drm->chan_nr = drm->chan_total = channels->data; > + drm->runl_nr = fls64(runlists->data); > drm->runl = kcalloc(drm->runl_nr, sizeof(*drm->runl), GFP_KERNEL); > if (!drm->runl) > return -ENOMEM; > > if (drm->chan_nr == 0) { > for (i = 0; i < drm->runl_nr; i++) { > - if (!(args.v.runlists.data & BIT(i))) > + if (!(runlists->data & BIT(i))) > continue; > > - args.v.channels.mthd = NV_DEVICE_HOST_RUNLIST_CHANNELS; > - args.v.channels.data = i; > + channels->mthd = NV_DEVICE_HOST_RUNLIST_CHANNELS; > + channels->data = i; > > - ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, &args, sizeof(args)); > - if (ret || args.v.channels.mthd == NV_DEVICE_INFO_INVALID) > + ret = nvif_object_mthd(device, NV_DEVICE_V0_INFO, args, > + __struct_size(args)); > + if (ret || channels->mthd == NV_DEVICE_INFO_INVALID) > return -ENODEV; > > - drm->runl[i].chan_nr = args.v.channels.data; > + drm->runl[i].chan_nr = channels->data; > drm->runl[i].chan_id_base = drm->chan_total; > drm->runl[i].context_base = dma_fence_context_alloc(drm->runl[i].chan_nr); >Otherwise looks good. -Kees -- Kees Cook