From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eyal Reizer , Tony Lindgren , Kalle Valo , Sasha Levin Subject: [PATCH 4.19 077/361] wlcore: Fix BUG with clear completion on timeout Date: Sun, 11 Nov 2018 14:17:04 -0800 Message-Id: <20181111221630.803995370@linuxfoundation.org> In-Reply-To: <20181111221619.915519183@linuxfoundation.org> References: <20181111221619.915519183@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tony Lindgren [ Upstream commit 4e651bad848955d88b29a568bfbfb4b831270e16 ] We do not currently clear wl->elp_compl on ELP timeout and we have bogus lingering pointer that wlcore_irq then will try to access after recovery is done: BUG: spinlock bad magic on CPU#1, irq/255-wl12xx/580 ... (spin_dump) from [] (do_raw_spin_lock+0xc8/0x124) (do_raw_spin_lock) from [] (_raw_spin_lock_irqsave+0x68/0x74) (_raw_spin_lock_irqsave) from [] (complete+0x24/0x58) (complete) from [] (wlcore_irq+0x48/0x17c [wlcore]) (wlcore_irq [wlcore]) from [] (irq_thread_fn+0x2c/0x64) (irq_thread_fn) from [] (irq_thread+0x148/0x290) (irq_thread) from [] (kthread+0x160/0x17c) (kthread) from [] (ret_from_fork+0x14/0x20) ... After that the system will hang. Let's fix this by adding a flag for recovery and moving the recovery work call to to the error handling section. And we want to set WL1271_FLAG_INTENDED_FW_RECOVERY and actually clear it too in wl1271_recovery_work() and just downgrade the error to a warning to prevent overly verbose output. Cc: Eyal Reizer Signed-off-by: Tony Lindgren Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/ti/wlcore/main.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) --- a/drivers/net/wireless/ti/wlcore/main.c +++ b/drivers/net/wireless/ti/wlcore/main.c @@ -957,6 +957,8 @@ static void wl1271_recovery_work(struct BUG_ON(wl->conf.recovery.bug_on_recovery && !test_bit(WL1271_FLAG_INTENDED_FW_RECOVERY, &wl->flags)); + clear_bit(WL1271_FLAG_INTENDED_FW_RECOVERY, &wl->flags); + if (wl->conf.recovery.no_recovery) { wl1271_info("No recovery (chosen on module load). Fw will remain stuck."); goto out_unlock; @@ -6710,6 +6712,7 @@ static int __maybe_unused wlcore_runtime int ret; unsigned long start_time = jiffies; bool pending = false; + bool recovery = false; /* Nothing to do if no ELP mode requested */ if (!test_bit(WL1271_FLAG_IN_ELP, &wl->flags)) @@ -6726,7 +6729,7 @@ static int __maybe_unused wlcore_runtime ret = wlcore_raw_write32(wl, HW_ACCESS_ELP_CTRL_REG, ELPCTRL_WAKE_UP); if (ret < 0) { - wl12xx_queue_recovery_work(wl); + recovery = true; goto err; } @@ -6734,11 +6737,12 @@ static int __maybe_unused wlcore_runtime ret = wait_for_completion_timeout(&compl, msecs_to_jiffies(WL1271_WAKEUP_TIMEOUT)); if (ret == 0) { - wl1271_error("ELP wakeup timeout!"); - wl12xx_queue_recovery_work(wl); + wl1271_warning("ELP wakeup timeout!"); /* Return no error for runtime PM for recovery */ - return 0; + ret = 0; + recovery = true; + goto err; } } @@ -6753,6 +6757,12 @@ err: spin_lock_irqsave(&wl->wl_lock, flags); wl->elp_compl = NULL; spin_unlock_irqrestore(&wl->wl_lock, flags); + + if (recovery) { + set_bit(WL1271_FLAG_INTENDED_FW_RECOVERY, &wl->flags); + wl12xx_queue_recovery_work(wl); + } + return ret; }