From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> [ Upstream commit ba6535e8b494931471df9666addf0f1e5e6efa27 ] Device can be unbound or probe can fail, so driver must also release memory for the wakeup source. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- **YES** This commit should be backported to stable kernel trees. Here's my extensive analysis: ## Analysis of the Commit ### 1. Nature of the Fix This commit addresses a **resource leak bug** in the btmrvl_sdio driver. The fix changes `device_init_wakeup(dev, true)` to `devm_device_init_wakeup(dev)`, which ensures automatic cleanup of wakeup sources when the device is unbound or probe fails. ### 2. Code Changes Analysis The specific changes are: ```diff - device_init_wakeup(dev, true); + ret = devm_device_init_wakeup(dev); + if (ret) + return dev_err_probe(dev, ret, "Failed to init wakeup\n"); ``` This change: - Replaces manual wakeup initialization with device- managed version - Adds proper error handling for the wakeup initialization - Ensures automatic cleanup when device is removed or probe fails ### 3. Comparison with Similar Commits This commit is **very similar to Similar Commit #3** (gpio: mpc8xxx), which: - Also fixes wakeup source leaks on device unbind - Uses the same pattern: `device_init_wakeup()` → `devm_device_init_wakeup()` - Has identical commit message structure and purpose - **Was marked for backporting (Status: YES)** The pattern is also similar to **Similar Commit #2** (btmrvl_sdio: Refactor irq wakeup), which was also backported (Status: YES) and dealt with wakeup handling improvements. ### 4. Stable Tree Criteria Assessment ✅ **Fixes important bug**: Resource leaks can cause system-wide issues ✅ **Small and contained**: Only changes 3 lines in one function ✅ **No architectural changes**: Uses existing kernel APIs ✅ **Minimal regression risk**: Device-managed resources are well- established ✅ **Clear side effects**: Only improves resource management ✅ **Affects users**: Anyone using btmrvl_sdio with wakeup functionality ### 5. Risk Analysis **Low Risk Factors:** - `devm_device_init_wakeup()` is a well-established API - The change follows standard kernel patterns for resource management - Error handling is improved with proper error propagation - Similar changes have been successfully backported (as shown in Similar Commit #3) **No Major Concerns:** - No changes to critical code paths - No new features introduced - No complex logic modifications ### 6. Impact Assessment **Positive Impact:** - Prevents wakeup source memory leaks - Improves system stability during device unbind/rebind cycles - Follows kernel best practices for resource management - Adds better error handling **User-Facing Benefit:** - Systems using btmrvl_sdio devices will be more stable - Proper cleanup during module unload or device removal - Better error reporting if wakeup initialization fails ### Conclusion This commit meets all the criteria for stable backporting: - It's a clear bugfix addressing resource leaks - The change is minimal and low-risk - It follows established patterns (identical to Similar Commit #3 which was backported) - It improves system stability without introducing new functionality - The fix is contained within a single driver subsystem The commit should be backported to ensure users don't experience wakeup source leaks when using btmrvl_sdio devices. drivers/bluetooth/btmrvl_sdio.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/btmrvl_sdio.c b/drivers/bluetooth/btmrvl_sdio.c index 07cd308f7abf6..93932a0d8625a 100644 --- a/drivers/bluetooth/btmrvl_sdio.c +++ b/drivers/bluetooth/btmrvl_sdio.c @@ -100,7 +100,9 @@ static int btmrvl_sdio_probe_of(struct device *dev, } /* Configure wakeup (enabled by default) */ - device_init_wakeup(dev, true); + ret = devm_device_init_wakeup(dev); + if (ret) + return dev_err_probe(dev, ret, "Failed to init wakeup\n"); } } -- 2.39.5
