It will cause memory leakage when use driver API devm_free_percpu() to free memory allocated by devm_alloc_percpu(), fixed by using devres_release() instead of devres_destroy() within devm_free_percpu().
Fixes: ff86aae3b411 ("devres: add devm_alloc_percpu()") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com --- drivers/base/devres.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 3df0025d12aa..082dbb296b6e 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -1222,7 +1222,11 @@ EXPORT_SYMBOL_GPL(__devm_alloc_percpu); */ void devm_free_percpu(struct device *dev, void __percpu *pdata) { - WARN_ON(devres_destroy(dev, devm_percpu_release, devm_percpu_match, + /* + * Use devres_release() to prevent memory leakage as + * devm_free_pages() does. + */ + WARN_ON(devres_release(dev, devm_percpu_release, devm_percpu_match, (__force void *)pdata)); } EXPORT_SYMBOL_GPL(devm_free_percpu);
On Wed, Jun 19, 2024 at 09:38:01PM +0800, Zijun Hu wrote:
It will cause memory leakage when use driver API devm_free_percpu() to free memory allocated by devm_alloc_percpu(), fixed by using devres_release() instead of devres_destroy() within devm_free_percpu().
Fixes: ff86aae3b411 ("devres: add devm_alloc_percpu()") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com
drivers/base/devres.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 3df0025d12aa..082dbb296b6e 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -1222,7 +1222,11 @@ EXPORT_SYMBOL_GPL(__devm_alloc_percpu); */ void devm_free_percpu(struct device *dev, void __percpu *pdata) {
- WARN_ON(devres_destroy(dev, devm_percpu_release, devm_percpu_match,
- /*
* Use devres_release() to prevent memory leakage as* devm_free_pages() does.*/- WARN_ON(devres_release(dev, devm_percpu_release, devm_percpu_match, (__force void *)pdata));
} EXPORT_SYMBOL_GPL(devm_free_percpu); -- 2.7.4
These are good fixes, how are you finding them? Care to write up some kunit tests for the devres apis?
thanks,
greg k-h
On 6/19/2024 10:53 PM, Greg KH wrote:
On Wed, Jun 19, 2024 at 09:38:01PM +0800, Zijun Hu wrote:
It will cause memory leakage when use driver API devm_free_percpu() to free memory allocated by devm_alloc_percpu(), fixed by using devres_release() instead of devres_destroy() within devm_free_percpu().
Fixes: ff86aae3b411 ("devres: add devm_alloc_percpu()") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com
drivers/base/devres.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 3df0025d12aa..082dbb296b6e 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -1222,7 +1222,11 @@ EXPORT_SYMBOL_GPL(__devm_alloc_percpu); */ void devm_free_percpu(struct device *dev, void __percpu *pdata) {
- WARN_ON(devres_destroy(dev, devm_percpu_release, devm_percpu_match,
- /*
* Use devres_release() to prevent memory leakage as* devm_free_pages() does.*/- WARN_ON(devres_release(dev, devm_percpu_release, devm_percpu_match, (__force void *)pdata));
} EXPORT_SYMBOL_GPL(devm_free_percpu); -- 2.7.4
These are good fixes, how are you finding them? Care to write up some kunit tests for the devres apis?
find them by reading code.😀
thanks,
greg k-h
linux-stable-mirror@lists.linaro.org
-
Greg KH -
quic_zijuhu -
Zijun Hu