[PATCH] Bluetooth: hci_bcm: fix usage_count leak when autosuspend_delay is negative

[PATCH] Bluetooth: hci_bcm: fix usage_count leak when autosuspend_delay is negative

[Guangshuo Li]

bcm_request_irq() calls pm_runtime_use_autosuspend(), but bcm_close()
does not call the matching pm_runtime_dont_use_autosuspend() when
tearing down runtime PM.

If the autosuspend delay is set to a negative value while autosuspend
is enabled, the runtime PM core increments usage_count to prevent
runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
during driver teardown, this reference is not dropped and usage_count
remains unbalanced.

Add the missing pm_runtime_dont_use_autosuspend() call before disabling
runtime PM.

This issue was found by manual code inspection.

Fixes: e88ab30d3669 ("Bluetooth: hci_bcm: Add suspend/resume runtime PM functions")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
 drivers/bluetooth/hci_bcm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 1a4fc3882fd2..cc419e1960de 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -547,6 +547,7 @@ static int bcm_close(struct hci_uart *hu)
 		if (IS_ENABLED(CONFIG_PM) && bdev->irq_acquired) {
 			devm_free_irq(bdev->dev, bdev->irq, bdev);
 			device_init_wakeup(bdev->dev, false);
+			pm_runtime_dont_use_autosuspend(bdev->dev);
 			pm_runtime_disable(bdev->dev);
 		}
 
-- 
2.43.0

Re: [PATCH] Bluetooth: hci_bcm: fix usage_count leak when autosuspend_delay is negative

[patchwork-bot+bluetooth]

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>:

On Sat,  8 Aug 2026 13:15:32 +0800 you wrote:
> bcm_request_irq() calls pm_runtime_use_autosuspend(), but bcm_close()
> does not call the matching pm_runtime_dont_use_autosuspend() when
> tearing down runtime PM.
> 
> If the autosuspend delay is set to a negative value while autosuspend
> is enabled, the runtime PM core increments usage_count to prevent
> runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
> during driver teardown, this reference is not dropped and usage_count
> remains unbalanced.
> 
> [...]

Here is the summary with links:
  - Bluetooth: hci_bcm: fix usage_count leak when autosuspend_delay is negative
    https://git.kernel.org/bluetooth/bluetooth-next/c/32b42c0704fd

You are awesome, thank you!
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