| Message ID | 1628246109-27425-1-git-send-email-loic.poulain@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [net-next] net: wwan: mhi_wwan_ctrl: Fix possible deadlock | expand |
On Fri, Aug 6, 2021 at 1:24 PM Loic Poulain <loic.poulain@linaro.org> wrote: > Lockdep detected possible interrupt unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&mhiwwan->rx_lock); > local_irq_disable(); > lock(&mhi_cntrl->pm_lock); > lock(&mhiwwan->rx_lock); > <Interrupt> > lock(&mhi_cntrl->pm_lock); > > *** DEADLOCK *** > > To prevent this we need to disable the soft-interrupts when taking > the rx_lock. > > Cc: stable@vger.kernel.org > Fixes: fa588eba632d ("net: Add Qcom WWAN control driver") > Reported-by: Thomas Perrot <thomas.perrot@bootlin.com> > Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Fri, 6 Aug 2021 12:35:09 +0200 you wrote: > Lockdep detected possible interrupt unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&mhiwwan->rx_lock); > local_irq_disable(); > lock(&mhi_cntrl->pm_lock); > lock(&mhiwwan->rx_lock); > <Interrupt> > lock(&mhi_cntrl->pm_lock); > > [...] Here is the summary with links: - [net-next] net: wwan: mhi_wwan_ctrl: Fix possible deadlock https://git.kernel.org/netdev/net/c/34737e1320db You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/drivers/net/wwan/mhi_wwan_ctrl.c b/drivers/net/wwan/mhi_wwan_ctrl.c index 1e18420..d0a98f3 100644 --- a/drivers/net/wwan/mhi_wwan_ctrl.c +++ b/drivers/net/wwan/mhi_wwan_ctrl.c @@ -41,14 +41,14 @@ struct mhi_wwan_dev { /* Increment RX budget and schedule RX refill if necessary */ static void mhi_wwan_rx_budget_inc(struct mhi_wwan_dev *mhiwwan) { - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); mhiwwan->rx_budget++; if (test_bit(MHI_WWAN_RX_REFILL, &mhiwwan->flags)) schedule_work(&mhiwwan->rx_refill); - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); } /* Decrement RX budget if non-zero and return true on success */ @@ -56,7 +56,7 @@ static bool mhi_wwan_rx_budget_dec(struct mhi_wwan_dev *mhiwwan) { bool ret = false; - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); if (mhiwwan->rx_budget) { mhiwwan->rx_budget--; @@ -64,7 +64,7 @@ static bool mhi_wwan_rx_budget_dec(struct mhi_wwan_dev *mhiwwan) ret = true; } - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); return ret; } @@ -130,9 +130,9 @@ static void mhi_wwan_ctrl_stop(struct wwan_port *port) { struct mhi_wwan_dev *mhiwwan = wwan_port_get_drvdata(port); - spin_lock(&mhiwwan->rx_lock); + spin_lock_bh(&mhiwwan->rx_lock); clear_bit(MHI_WWAN_RX_REFILL, &mhiwwan->flags); - spin_unlock(&mhiwwan->rx_lock); + spin_unlock_bh(&mhiwwan->rx_lock); cancel_work_sync(&mhiwwan->rx_refill);
Lockdep detected possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mhiwwan->rx_lock); local_irq_disable(); lock(&mhi_cntrl->pm_lock); lock(&mhiwwan->rx_lock); <Interrupt> lock(&mhi_cntrl->pm_lock); *** DEADLOCK *** To prevent this we need to disable the soft-interrupts when taking the rx_lock. Cc: stable@vger.kernel.org Fixes: fa588eba632d ("net: Add Qcom WWAN control driver") Reported-by: Thomas Perrot <thomas.perrot@bootlin.com> Signed-off-by: Loic Poulain <loic.poulain@linaro.org> --- drivers/net/wwan/mhi_wwan_ctrl.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)