6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bill Wendling morbo@google.com
commit 2bac084468847cfe5bbc7166082b2a208514bb1c upstream.
Work for __counted_by on generic pointers in structures (not just flexible array members) has started landing in Clang 19 (current tip of tree). During the development of this feature, a restriction was added to __counted_by to prevent the flexible array member's element type from including a flexible array member itself such as:
struct foo { int count; char buf[]; };
struct bar { int count; struct foo data[] __counted_by(count); };
because the size of data cannot be calculated with the standard array size formula:
sizeof(struct foo) * count
This restriction was downgraded to a warning but due to CONFIG_WERROR, it can still break the build. The application of __counted_by on the states member of 'struct _StateArray' triggers this restriction, resulting in:
drivers/gpu/drm/radeon/pptable.h:442:5: error: 'counted_by' should not be applied to an array with element of unknown size because 'ATOM_PPLIB_STATE_V2' (aka 'struct _ATOM_PPLIB_STATE_V2') is a struct type with a flexible array member. This will be an error in a future compiler version [-Werror,-Wbounds-safety-counted-by-elt-type-unknown-size] 442 | ATOM_PPLIB_STATE_V2 states[] __counted_by(ucNumEntries); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated.
Remove this use of __counted_by to fix the warning/error. However, rather than remove it altogether, leave it commented, as it may be possible to support this in future compiler releases.
Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/2028 Fixes: efade6fe50e7 ("drm/radeon: silence UBSAN warning (v3)") Signed-off-by: Bill Wendling morbo@google.com Co-developed-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/radeon/pptable.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/radeon/pptable.h +++ b/drivers/gpu/drm/radeon/pptable.h @@ -439,7 +439,7 @@ typedef struct _StateArray{ //how many states we have UCHAR ucNumEntries;
- ATOM_PPLIB_STATE_V2 states[] __counted_by(ucNumEntries); + ATOM_PPLIB_STATE_V2 states[] /* __counted_by(ucNumEntries) */; }StateArray;