From 46c501473d0a6fa62435dfd65c6884e1fd63b327 Mon Sep 17 00:00:00 2001 From: Inaky Perez-Gonzalez Date: Wed, 7 Oct 2009 22:46:29 +0900 Subject: [PATCH] wimax/i2400m: fix oops in TX when tearing down the device All the entry points into the TX module should check if the device has been torn down. Otherwise, when the device resets or shuts down, there are windows when a call to i2400m_tx*() will oops the system. For that, make i2400m_tx_release() set i2400m->tx_buf to NULL under the tx_lock. Then, any entry point [i2400m_tx(), _tx_msg_sent(), _tx_msg_get()] will check for i2400m->tx_buf to be NULL and exit gracefully. Signed-off-by: Inaky Perez-Gonzalez --- drivers/net/wimax/i2400m/sdio-tx.c | 5 ++++- drivers/net/wimax/i2400m/tx.c | 18 +++++++++++++++++- 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/net/wimax/i2400m/sdio-tx.c b/drivers/net/wimax/i2400m/sdio-tx.c index 5105a5ebc44f..de66d068c9cb 100644 --- a/drivers/net/wimax/i2400m/sdio-tx.c +++ b/drivers/net/wimax/i2400m/sdio-tx.c @@ -149,5 +149,8 @@ int i2400ms_tx_setup(struct i2400ms *i2400ms) void i2400ms_tx_release(struct i2400ms *i2400ms) { - destroy_workqueue(i2400ms->tx_workqueue); + if (i2400ms->tx_workqueue) { + destroy_workqueue(i2400ms->tx_workqueue); + i2400ms->tx_workqueue = NULL; + } } diff --git a/drivers/net/wimax/i2400m/tx.c b/drivers/net/wimax/i2400m/tx.c index 8c2080248aec..54480e8947f1 100644 --- a/drivers/net/wimax/i2400m/tx.c +++ b/drivers/net/wimax/i2400m/tx.c @@ -642,6 +642,9 @@ int i2400m_tx(struct i2400m *i2400m, const void *buf, size_t buf_len, * current one is out of payload slots or we have a singleton, * close it and start a new one */ spin_lock_irqsave(&i2400m->tx_lock, flags); + result = -ESHUTDOWN; + if (i2400m->tx_buf == NULL) + goto error_tx_new; try_new: if (unlikely(i2400m->tx_msg == NULL)) i2400m_tx_new(i2400m); @@ -697,7 +700,10 @@ try_new: } error_tx_new: spin_unlock_irqrestore(&i2400m->tx_lock, flags); - i2400m->bus_tx_kick(i2400m); /* always kick, might free up space */ + /* kick in most cases, except when the TX subsys is down, as + * it might free space */ + if (likely(result != -ESHUTDOWN)) + i2400m->bus_tx_kick(i2400m); d_fnend(3, dev, "(i2400m %p skb %p [%zu bytes] pt %u) = %d\n", i2400m, buf, buf_len, pl_type, result); return result; @@ -740,6 +746,9 @@ struct i2400m_msg_hdr *i2400m_tx_msg_get(struct i2400m *i2400m, d_fnstart(3, dev, "(i2400m %p bus_size %p)\n", i2400m, bus_size); spin_lock_irqsave(&i2400m->tx_lock, flags); + tx_msg_moved = NULL; + if (i2400m->tx_buf == NULL) + goto out_unlock; skip: tx_msg_moved = NULL; if (i2400m->tx_in == i2400m->tx_out) { /* Empty FIFO? */ @@ -829,6 +838,8 @@ void i2400m_tx_msg_sent(struct i2400m *i2400m) d_fnstart(3, dev, "(i2400m %p)\n", i2400m); spin_lock_irqsave(&i2400m->tx_lock, flags); + if (i2400m->tx_buf == NULL) + goto out_unlock; i2400m->tx_out += i2400m->tx_msg_size; d_printf(2, dev, "TX: sent %zu b\n", (size_t) i2400m->tx_msg_size); i2400m->tx_msg_size = 0; @@ -837,6 +848,7 @@ void i2400m_tx_msg_sent(struct i2400m *i2400m) n = i2400m->tx_out / I2400M_TX_BUF_SIZE; i2400m->tx_out %= I2400M_TX_BUF_SIZE; i2400m->tx_in -= n * I2400M_TX_BUF_SIZE; +out_unlock: spin_unlock_irqrestore(&i2400m->tx_lock, flags); d_fnend(3, dev, "(i2400m %p) = void\n", i2400m); } @@ -876,5 +888,9 @@ int i2400m_tx_setup(struct i2400m *i2400m) */ void i2400m_tx_release(struct i2400m *i2400m) { + unsigned long flags; + spin_lock_irqsave(&i2400m->tx_lock, flags); kfree(i2400m->tx_buf); + i2400m->tx_buf = NULL; + spin_unlock_irqrestore(&i2400m->tx_lock, flags); }