Nouveau - Aug 2023 - [PATCH 2/2][next] nouveau/svm: Split assignment from if conditional

This small series aims to replace a one-element array with a
flexible-array member in struct nouveau_svm. And, while at it,
fix a checkpatch.pl error.

Gustavo A. R. Silva (2):
  nouveau/svm: Replace one-element array with flexible-array member in
    struct nouveau_svm
  nouveau/svm: Split assignment from if conditional

 drivers/gpu/drm/nouveau/nouveau_svm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

-- 
2.34.1

One-element and zero-length arrays are deprecated. So, replace
one-element array in struct nouveau_svm with flexible-array member.

This results in no differences in binary output.

Link: https://github.com/KSPP/linux/issues/338
Signed-off-by: Gustavo A. R. Silva <gustavoars at kernel.org>
---
 drivers/gpu/drm/nouveau/nouveau_svm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c
b/drivers/gpu/drm/nouveau/nouveau_svm.c
index 186351ecf72f..00444ad82d18 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -67,7 +67,7 @@ struct nouveau_svm {
 			struct nouveau_svmm *svmm;
 		} **fault;
 		int fault_nr;
-	} buffer[1];
+	} buffer[];
 };
 
 #define FAULT_ACCESS_READ 0
@@ -1063,7 +1063,7 @@ nouveau_svm_init(struct nouveau_drm *drm)
 	if (drm->client.device.info.family > NV_DEVICE_INFO_V0_PASCAL)
 		return;
 
-	if (!(drm->svm = svm = kzalloc(sizeof(*drm->svm), GFP_KERNEL)))
+	if (!(drm->svm = svm = kzalloc(struct_size(drm->svm, buffer, 1),
GFP_KERNEL)))
 		return;
 
 	drm->svm->drm = drm;
-- 
2.34.1

Fix checkpatch.pl ERROR: do not use assignment in if condition.

Signed-off-by: Gustavo A. R. Silva <gustavoars at kernel.org>
---
 drivers/gpu/drm/nouveau/nouveau_svm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c
b/drivers/gpu/drm/nouveau/nouveau_svm.c
index 00444ad82d18..cc03e0c22ff3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -1063,7 +1063,8 @@ nouveau_svm_init(struct nouveau_drm *drm)
 	if (drm->client.device.info.family > NV_DEVICE_INFO_V0_PASCAL)
 		return;
 
-	if (!(drm->svm = svm = kzalloc(struct_size(drm->svm, buffer, 1),
GFP_KERNEL)))
+	drm->svm = svm = kzalloc(struct_size(drm->svm, buffer, 1), GFP_KERNEL);
+	if (!drm->svm)
 		return;
 
 	drm->svm->drm = drm;
-- 
2.34.1

On Wed, 16 Aug 2023 12:03:06 -0600, Gustavo A. R. Silva
wrote:
> This small series aims to replace a one-element array with a
> flexible-array member in struct nouveau_svm. And, while at it,
> fix a checkpatch.pl error.
> 
> Gustavo A. R. Silva (2):
>   nouveau/svm: Replace one-element array with flexible-array member in
>     struct nouveau_svm
>   nouveau/svm: Split assignment from if conditional
> 
> [...]
These look trivially correct and haven't had further feedback for over a
month.

Applied to for-next/hardening, thanks!

[1/2] nouveau/svm: Replace one-element array with flexible-array member in
struct nouveau_svm
      https://git.kernel.org/kees/c/6ad33b53c9b8
[2/2] nouveau/svm: Split assignment from if conditional
      https://git.kernel.org/kees/c/4cb2e89fea5f

Take care,

-- 
Kees Cook