accel/amdxdna: Fix dead lock for suspend and resume

When an application issues a query IOCTL while auto suspend is running,
a deadlock can occur. The query path holds dev_lock and then calls
pm_runtime_resume_and_get(), which waits for the ongoing suspend to
complete. Meanwhile, the suspend callback attempts to acquire dev_lock
and blocks, resulting in a deadlock.

Fix this by releasing dev_lock before calling pm_runtime_resume_and_get()
and reacquiring it after the call completes. Also acquire dev_lock in the
resume callback to keep the locking consistent.

Fixes: 063db451832b ("accel/amdxdna: Enhance runtime power management")
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
Link: https://patch.msgid.link/20260211204644.722758-1-lizhi.hou@amd.com

diff --git a/drivers/accel/amdxdna/aie2_ctx.c b/drivers/accel/amdxdna/aie2_ctx.c
index e13be76084620f40bf60eaa8c4da99577cf04835..8d79fafd889a085356a990e59b029c7d0a3bdf99 100644 (file)
--- a/drivers/accel/amdxdna/aie2_ctx.c
+++ b/drivers/accel/amdxdna/aie2_ctx.c
@@ -629,7 +629,7 @@ int aie2_hwctx_init(struct amdxdna_hwctx *hwctx)
                goto free_entity;
        }
 
-       ret = amdxdna_pm_resume_get(xdna);
+       ret = amdxdna_pm_resume_get_locked(xdna);
        if (ret)
                goto free_col_list;
 
@@ -760,7 +760,7 @@ static int aie2_hwctx_cu_config(struct amdxdna_hwctx *hwctx, void *buf, u32 size
        if (!hwctx->cus)
                return -ENOMEM;
 
-       ret = amdxdna_pm_resume_get(xdna);
+       ret = amdxdna_pm_resume_get_locked(xdna);
        if (ret)
                goto free_cus;
 

diff --git a/drivers/accel/amdxdna/aie2_pci.c b/drivers/accel/amdxdna/aie2_pci.c
index 2a51b2658bfcd84626855ca7f3574f5dbfe15f7a..07e3695078189e67d9c8e4e3d18be58af6ef0235 100644 (file)
--- a/drivers/accel/amdxdna/aie2_pci.c
+++ b/drivers/accel/amdxdna/aie2_pci.c
@@ -451,7 +451,6 @@ static int aie2_hw_suspend(struct amdxdna_dev *xdna)
 {
        struct amdxdna_client *client;
 
-       guard(mutex)(&xdna->dev_lock);
        list_for_each_entry(client, &xdna->client_list, node)
                aie2_hwctx_suspend(client);
 
@@ -951,7 +950,7 @@ static int aie2_get_info(struct amdxdna_client *client, struct amdxdna_drm_get_i
        if (!drm_dev_enter(&xdna->ddev, &idx))
                return -ENODEV;
 
-       ret = amdxdna_pm_resume_get(xdna);
+       ret = amdxdna_pm_resume_get_locked(xdna);
        if (ret)
                goto dev_exit;
 
@@ -1044,7 +1043,7 @@ static int aie2_get_array(struct amdxdna_client *client,
        if (!drm_dev_enter(&xdna->ddev, &idx))
                return -ENODEV;
 
-       ret = amdxdna_pm_resume_get(xdna);
+       ret = amdxdna_pm_resume_get_locked(xdna);
        if (ret)
                goto dev_exit;
 
@@ -1134,7 +1133,7 @@ static int aie2_set_state(struct amdxdna_client *client,
        if (!drm_dev_enter(&xdna->ddev, &idx))
                return -ENODEV;
 
-       ret = amdxdna_pm_resume_get(xdna);
+       ret = amdxdna_pm_resume_get_locked(xdna);
        if (ret)
                goto dev_exit;
 

diff --git a/drivers/accel/amdxdna/aie2_pm.c b/drivers/accel/amdxdna/aie2_pm.c
index 579b8be13b1804519c391b805206129df7a4fd6e..29bd4403a94d449c4483f41ab6354b2b78b80e40 100644 (file)
--- a/drivers/accel/amdxdna/aie2_pm.c
+++ b/drivers/accel/amdxdna/aie2_pm.c
@@ -31,7 +31,7 @@ int aie2_pm_set_dpm(struct amdxdna_dev_hdl *ndev, u32 dpm_level)
 {
        int ret;
 
-       ret = amdxdna_pm_resume_get(ndev->xdna);
+       ret = amdxdna_pm_resume_get_locked(ndev->xdna);
        if (ret)
                return ret;
 

diff --git a/drivers/accel/amdxdna/amdxdna_ctx.c b/drivers/accel/amdxdna/amdxdna_ctx.c
index 59fa3800b9d3f4453a1eb132ae0a7c74ea993c06..5173456bbb6125d4c87f5cb3444f0e78c70014f6 100644 (file)
--- a/drivers/accel/amdxdna/amdxdna_ctx.c
+++ b/drivers/accel/amdxdna/amdxdna_ctx.c
@@ -266,9 +266,9 @@ int amdxdna_drm_config_hwctx_ioctl(struct drm_device *dev, void *data, struct dr
        struct amdxdna_drm_config_hwctx *args = data;
        struct amdxdna_dev *xdna = to_xdna_dev(dev);
        struct amdxdna_hwctx *hwctx;
-       int ret, idx;
        u32 buf_size;
        void *buf;
+       int ret;
        u64 val;
 
        if (XDNA_MBZ_DBG(xdna, &args->pad, sizeof(args->pad)))
@@ -310,20 +310,17 @@ int amdxdna_drm_config_hwctx_ioctl(struct drm_device *dev, void *data, struct dr
                return -EINVAL;
        }
 
-       mutex_lock(&xdna->dev_lock);
-       idx = srcu_read_lock(&client->hwctx_srcu);
+       guard(mutex)(&xdna->dev_lock);
        hwctx = xa_load(&client->hwctx_xa, args->handle);
        if (!hwctx) {
                XDNA_DBG(xdna, "PID %d failed to get hwctx %d", client->pid, args->handle);
                ret = -EINVAL;
-               goto unlock_srcu;
+               goto free_buf;
        }
 
        ret = xdna->dev_info->ops->hwctx_config(hwctx, args->param_type, val, buf, buf_size);
 
-unlock_srcu:
-       srcu_read_unlock(&client->hwctx_srcu, idx);
-       mutex_unlock(&xdna->dev_lock);
+free_buf:
        kfree(buf);
        return ret;
 }
@@ -334,7 +331,7 @@ int amdxdna_hwctx_sync_debug_bo(struct amdxdna_client *client, u32 debug_bo_hdl)
        struct amdxdna_hwctx *hwctx;
        struct amdxdna_gem_obj *abo;
        struct drm_gem_object *gobj;
-       int ret, idx;
+       int ret;
 
        if (!xdna->dev_info->ops->hwctx_sync_debug_bo)
                return -EOPNOTSUPP;
@@ -345,17 +342,15 @@ int amdxdna_hwctx_sync_debug_bo(struct amdxdna_client *client, u32 debug_bo_hdl)
 
        abo = to_xdna_obj(gobj);
        guard(mutex)(&xdna->dev_lock);
-       idx = srcu_read_lock(&client->hwctx_srcu);
        hwctx = xa_load(&client->hwctx_xa, abo->assigned_hwctx);
        if (!hwctx) {
                ret = -EINVAL;
-               goto unlock_srcu;
+               goto put_obj;
        }
 
        ret = xdna->dev_info->ops->hwctx_sync_debug_bo(hwctx, debug_bo_hdl);
 
-unlock_srcu:
-       srcu_read_unlock(&client->hwctx_srcu, idx);
+put_obj:
        drm_gem_object_put(gobj);
        return ret;
 }

diff --git a/drivers/accel/amdxdna/amdxdna_pm.c b/drivers/accel/amdxdna/amdxdna_pm.c
index d024d480521c4964ae7c0c789e201884633ca72f..b1fafddd7ad5970526c124a00c5ed8c70267b39b 100644 (file)
--- a/drivers/accel/amdxdna/amdxdna_pm.c
+++ b/drivers/accel/amdxdna/amdxdna_pm.c
@@ -16,6 +16,7 @@ int amdxdna_pm_suspend(struct device *dev)
        struct amdxdna_dev *xdna = to_xdna_dev(dev_get_drvdata(dev));
        int ret = -EOPNOTSUPP;
 
+       guard(mutex)(&xdna->dev_lock);
        if (xdna->dev_info->ops->suspend)
                ret = xdna->dev_info->ops->suspend(xdna);
 
@@ -28,6 +29,7 @@ int amdxdna_pm_resume(struct device *dev)
        struct amdxdna_dev *xdna = to_xdna_dev(dev_get_drvdata(dev));
        int ret = -EOPNOTSUPP;
 
+       guard(mutex)(&xdna->dev_lock);
        if (xdna->dev_info->ops->resume)
                ret = xdna->dev_info->ops->resume(xdna);
 

diff --git a/drivers/accel/amdxdna/amdxdna_pm.h b/drivers/accel/amdxdna/amdxdna_pm.h
index 77b2d6e4557001a52aa3464ead1b77321072663b..3d26b973e0e36b7c5abb2bf791a9e4e89f8b3dc2 100644 (file)
--- a/drivers/accel/amdxdna/amdxdna_pm.h
+++ b/drivers/accel/amdxdna/amdxdna_pm.h
@@ -15,4 +15,15 @@ void amdxdna_pm_suspend_put(struct amdxdna_dev *xdna);
 void amdxdna_pm_init(struct amdxdna_dev *xdna);
 void amdxdna_pm_fini(struct amdxdna_dev *xdna);
 
+static inline int amdxdna_pm_resume_get_locked(struct amdxdna_dev *xdna)
+{
+       int ret;
+
+       mutex_unlock(&xdna->dev_lock);
+       ret = amdxdna_pm_resume_get(xdna);
+       mutex_lock(&xdna->dev_lock);
+
+       return ret;
+}
+
 #endif /* _AMDXDNA_PM_H_ */