I suspect this won't work correctly. If the profiler locks the device
multiple times, it probably also unlocks it multiple times. But I see no
reference counting being done, so this may result in a situation where
user mode locks twice, and unlocks once. Now it's lost the lock but it
was still expecting to have it from the first lock operation.
I suspect that this is a user mode bug, and KFD is working as expected.
Regards,
Felix
On 2026-08-12 03:14, Zhu, Lingshan wrote:
AMD General
Gentle Ping.
Thanks
Lingshan
-----Original Message-----
From: Zhu, Lingshan <[email protected]>
Sent: Thursday, August 6, 2026 4:43 PM
To: Deucher, Alexander <[email protected]>; Koenig, Christian
<[email protected]>; Kuehling, Felix <[email protected]>
Cc: Huang, Ray <[email protected]>; [email protected]; Zhu, Lingshan
<[email protected]>
Subject: [PATCH] amdkfd: allow profiler process reenter
profile_lock_device() currently returns -EALREADY when the current profiler
process requests to lock the device again. However any negtive values here are
treated as failure, so this causes rejecting a profiler operation even though
the caller still owns the device locking.
This commit fixes this problem by returning 0 when the current profiler process
locking the device again.
This commit also changes profile_lock_device() to return an int value other
than uint32_t, because it returns negative number when fail.
Signed-off-by: Zhu Lingshan <[email protected]>
---
drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 309510e23315..9acd5c91e51c 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -3329,8 +3329,8 @@ static int kfd_ioctl_create_process(struct file *filep,
struct kfd_process *p, v
return 0;
}
-static inline uint32_t profile_lock_device(struct kfd_process *p,
- uint32_t gpu_id, uint32_t op)
+static inline int profile_lock_device(struct kfd_process *p,
+ uint32_t gpu_id, uint32_t op)
{
struct kfd_process_device *pdd;
struct kfd_dev *kfd;
@@ -3365,7 +3365,7 @@ static inline uint32_t profile_lock_device(struct
kfd_process *p,
}
return status;
} else if (kfd->profiler_process == p) {
- status = -EALREADY;
+ status = 0;
} else {
status = -EBUSY;
}
--
2.53.0
