After commit a3866ce7b122 ("drm/xe: Add vm to exec queues association"),
building for an architecture other than x86 (which defines its own
_THIS_IP_) with clang fails with:
drivers/gpu/drm/xe/xe_vm.c:1586:3: error: cannot jump from this indirect goto
statement to one of its possible targets
1586 | drm_exec_retry_on_contention(&exec);
| ^
include/drm/drm_exec.h:123:4: note: expanded from macro
'drm_exec_retry_on_contention'
123 | goto *__drm_exec_retry_ptr; \
| ^
drivers/gpu/drm/xe/xe_vm.c:1542:3: note: possible target of indirect goto
statement
1542 | might_lock(&vm->exec_queues.lock);
| ^
include/linux/lockdep.h:553:33: note: expanded from macro 'might_lock'
553 | lock_release(&(lock)->dep_map, _THIS_IP_);
\
| ^
include/linux/instruction_pointer.h:10:41: note: expanded from macro
'_THIS_IP_'
10 | #define _THIS_IP_ ({ __label__ __here; __here: (unsigned
long)&&__here; })
| ^
drivers/gpu/drm/xe/xe_vm.c:1583:2: note: jump exits scope of variable with
__attribute__((cleanup))
1583 | xe_validation_guard(&ctx, &xe->val, &exec, (struct
xe_val_flags) {.interruptible = true},
| ^
drivers/gpu/drm/xe/xe_validation.h:189:2: note: expanded from macro
'xe_validation_guard'
189 | scoped_guard(xe_validation, _ctx, _val, _exec, _flags, &_ret)
\
| ^
include/linux/cleanup.h:442:2: note: expanded from macro 'scoped_guard'
442 | __scoped_guard(_name, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:433:20: note: expanded from macro '__scoped_guard'
433 | for (CLASS(_name, scope)(args);
\
| ^
drivers/gpu/drm/xe/xe_vm.c:1542:3: note: jump enters a statement expression
1542 | might_lock(&vm->exec_queues.lock);
| ^
include/linux/lockdep.h:553:33: note: expanded from macro 'might_lock'
553 | lock_release(&(lock)->dep_map, _THIS_IP_);
\
| ^
include/linux/instruction_pointer.h:10:20: note: expanded from macro
'_THIS_IP_'
10 | #define _THIS_IP_ ({ __label__ __here; __here: (unsigned
long)&&__here; })
| ^
While this is a false positive error because __drm_exec_retry_ptr is
only ever assigned the label in drm_exec_until_all_locked() (thus it can
never jump over the cleanup variable), this error is not unreasonable in
general because the only supported use case for taking the address of a
label is computed gotos [1]. The kernel's use of the address of a label
in _THIS_IP_ is considered problematic by both GCC [2][3] and clang [4]
but they need to provide something equivalent before they can break this
use case.
Hide the usage of _THIS_IP_ by moving the CONFIG_PROVE_LOCKING if
statement to its own function, avoiding the error. This is similar to
commit 187e16f69de2 ("drm/xe: Work around clang multiple goto-label
error") but with the sources of _THIS_IP_.
Fixes: a3866ce7b122 ("drm/xe: Add vm to exec queues association")
Link: https://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html [1]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=44298 [2]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120071 [3]
Link: https://github.com/llvm/llvm-project/issues/138272 [4]
Signed-off-by: Nathan Chancellor <[email protected]>
---
drivers/gpu/drm/xe/xe_vm.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index f7bb21ac1987..293b92ed2fdd 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -1474,6 +1474,20 @@ static void xe_vm_pt_destroy(struct xe_vm *vm)
}
}
+static void xe_vm_init_prove_locking(struct xe_device *xe, struct xe_vm *vm)
+{
+ if (!IS_ENABLED(CONFIG_PROVE_LOCKING))
+ return;
+
+ fs_reclaim_acquire(GFP_KERNEL);
+ might_lock(&vm->exec_queues.lock);
+ fs_reclaim_release(GFP_KERNEL);
+
+ down_read(&vm->exec_queues.lock);
+ might_lock(&xe_root_mmio_gt(xe)->uc.guc.ct.lock);
+ up_read(&vm->exec_queues.lock);
+}
+
struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags, struct xe_file
*xef)
{
struct drm_gem_object *vm_resv_obj;
@@ -1537,15 +1551,7 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32
flags, struct xe_file *xef)
vm->preempt.min_run_period_ms = xe->min_run_period_lr_ms;
init_rwsem(&vm->exec_queues.lock);
- if (IS_ENABLED(CONFIG_PROVE_LOCKING)) {
- fs_reclaim_acquire(GFP_KERNEL);
- might_lock(&vm->exec_queues.lock);
- fs_reclaim_release(GFP_KERNEL);
-
- down_read(&vm->exec_queues.lock);
- might_lock(&xe_root_mmio_gt(xe)->uc.guc.ct.lock);
- up_read(&vm->exec_queues.lock);
- }
+ xe_vm_init_prove_locking(xe, vm);
for_each_tile(tile, xe, id)
xe_range_fence_tree_init(&vm->rftree[id]);
---
base-commit: 9dd1048bca4fe2aa67c7a286bafb3947537adedb
change-id: 20260121-xe-vm-fix-clang-goto-error-b23c9d6bbf68
Best regards,
--
Nathan Chancellor <[email protected]>
