| Message ID | 20220310232707.44251-1-dossche.niels@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 46b348fd2d81a341b15fb3f3f986204b038f5c42 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v2] alx: acquire mutex for alx_reinit in alx_change_mtu | expand |
Hello: This patch was applied to netdev/net.git (master) by Jakub Kicinski <kuba@kernel.org>: On Fri, 11 Mar 2022 00:27:08 +0100 you wrote: > alx_reinit has a lockdep assertion that the alx->mtx mutex must be held. > alx_reinit is called from two places: alx_reset and alx_change_mtu. > alx_reset does acquire alx->mtx before calling alx_reinit. > alx_change_mtu does not acquire this mutex, nor do its callers or any > path towards alx_change_mtu. > Acquire the mutex in alx_change_mtu. > > [...] Here is the summary with links: - [v2] alx: acquire mutex for alx_reinit in alx_change_mtu https://git.kernel.org/netdev/net/c/46b348fd2d81 You are awesome, thank you!
diff --git a/drivers/net/ethernet/atheros/alx/main.c b/drivers/net/ethernet/atheros/alx/main.c index 4ad3fc72e74e..a89b93cb4e26 100644 --- a/drivers/net/ethernet/atheros/alx/main.c +++ b/drivers/net/ethernet/atheros/alx/main.c @@ -1181,8 +1181,11 @@ static int alx_change_mtu(struct net_device *netdev, int mtu) alx->hw.mtu = mtu; alx->rxbuf_size = max(max_frame, ALX_DEF_RXBUF_SIZE); netdev_update_features(netdev); - if (netif_running(netdev)) + if (netif_running(netdev)) { + mutex_lock(&alx->mtx); alx_reinit(alx); + mutex_unlock(&alx->mtx); + } return 0; }
alx_reinit has a lockdep assertion that the alx->mtx mutex must be held. alx_reinit is called from two places: alx_reset and alx_change_mtu. alx_reset does acquire alx->mtx before calling alx_reinit. alx_change_mtu does not acquire this mutex, nor do its callers or any path towards alx_change_mtu. Acquire the mutex in alx_change_mtu. The issue was introduced when the fine-grained locking was introduced to the code to replace the RTNL. The same commit also introduced the lockdep assertion. Fixes: 4a5fe57e7751 ("alx: use fine-grained locking instead of RTNL") Signed-off-by: Niels Dossche <dossche.niels@gmail.com> --- Changes in v2: - Added Fixes tag and explainer drivers/net/ethernet/atheros/alx/main.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)