drm/amdgpu/debugfs: fix ref count leak when pm_runtime_get_sync fails

The call to pm_runtime_get_sync increments the counter even in case of
failure, leading to incorrect ref count.
In case of failure, decrement the ref count before returning.

Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 70 insertions, 25 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
index 0ac9aab69497..aeada7c9fbea 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -223,12 +223,16 @@ static int  amdgpu_debugfs_process_reg_op(bool read, struct file *f,
 	*pos &= (1UL << 22) - 1;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	if (use_bank) {
 		if ((sh_bank != 0xFFFFFFFF && sh_bank >= adev->gfx.config.max_sh_per_se) ||
@@ -332,12 +336,16 @@ static ssize_t amdgpu_debugfs_regs_pcie_read(struct file *f, char __user *buf,
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -387,12 +395,16 @@ static ssize_t amdgpu_debugfs_regs_pcie_write(struct file *f, const char __user
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -443,12 +455,16 @@ static ssize_t amdgpu_debugfs_regs_didt_read(struct file *f, char __user *buf,
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -498,12 +514,16 @@ static ssize_t amdgpu_debugfs_regs_didt_write(struct file *f, const char __user
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -554,12 +574,16 @@ static ssize_t amdgpu_debugfs_regs_smc_read(struct file *f, char __user *buf,
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -609,12 +633,16 @@ static ssize_t amdgpu_debugfs_regs_smc_write(struct file *f, const char __user *
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -764,12 +792,16 @@ static ssize_t amdgpu_debugfs_sensor_read(struct file *f, char __user *buf,
 	valuesize = sizeof(values);
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_dpm_read_sensor(adev, idx, &values[0], &valuesize);
 
@@ -842,12 +874,16 @@ static ssize_t amdgpu_debugfs_wave_read(struct file *f, char __user *buf,
 	simd = (*pos & GENMASK_ULL(44, 37)) >> 37;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	r = amdgpu_virt_enable_access_debugfs(adev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	/* switch to the specific se/sh/cu */
 	mutex_lock(&adev->grbm_idx_mutex);
@@ -981,6 +1017,7 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
 	return result;
 
 err:
+	pm_runtime_put_autosuspend(adev->ddev->dev);
 	kfree(data);
 	return r;
 }
@@ -1006,8 +1043,10 @@ static ssize_t amdgpu_debugfs_gfxoff_write(struct file *f, const char __user *bu
 		return -EINVAL;
 
 	r = pm_runtime_get_sync(adev->ddev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	while (size) {
 		uint32_t value;
@@ -1143,8 +1182,10 @@ static int amdgpu_debugfs_test_ib(struct seq_file *m, void *data)
 	int r = 0, i;
 
 	r = pm_runtime_get_sync(dev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	/* Avoid accidently unparking the sched thread during GPU reset */
 	mutex_lock(&adev->lock_reset);
@@ -1200,8 +1241,10 @@ static int amdgpu_debugfs_evict_vram(struct seq_file *m, void *data)
 	int r;
 
 	r = pm_runtime_get_sync(dev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	seq_printf(m, "(%d)\n", amdgpu_bo_evict_vram(adev));
 
@@ -1219,8 +1262,10 @@ static int amdgpu_debugfs_evict_gtt(struct seq_file *m, void *data)
 	int r;
 
 	r = pm_runtime_get_sync(dev->dev);
-	if (r < 0)
+	if (r < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return r;
+	}
 
 	seq_printf(m, "(%d)\n", ttm_bo_evict_mm(&adev->mman.bdev, TTM_PL_TT));
 
@@ -1410,16 +1455,16 @@ static int amdgpu_debugfs_sclk_set(void *data, u64 val)
 		return -EINVAL;
 
 	ret = pm_runtime_get_sync(adev->ddev->dev);
-	if (ret < 0)
+	if (ret < 0) {
+		pm_runtime_put_autosuspend(adev->ddev->dev);
 		return ret;
+	}
 
 	if (is_support_sw_smu(adev)) {
 		ret = smu_get_dpm_freq_range(&adev->smu, SMU_SCLK, &min_freq, &max_freq, true);
 		if (ret || val > max_freq || val < min_freq)
 			return -EINVAL;
 		ret = smu_set_soft_freq_range(&adev->smu, SMU_SCLK, (uint32_t)val, (uint32_t)val, true);
-	} else {
-		return 0;
 	}
 
 	pm_runtime_mark_last_busy(adev->ddev->dev);