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| author | Cindy H Kao <cindy.h.kao@intel.com> | 2009-08-27 15:25:12 -0700 |
|---|---|---|
| committer | Inaky Perez-Gonzalez <inaky@linux.intel.com> | 2009-10-19 15:55:33 +0900 |
| commit | 5b45bfe5010ae1ddaac463d1bcdb141a4ff4ff66 (patch) | |
| tree | 8115ce638a420e4ba6610ea6c2e126ddb9180b86 /drivers/net | |
| parent | 663ebb4aa2fd0d19e3d1da0fed3fa3fa134a4ef0 (diff) | |
| download | linux-5b45bfe5010ae1ddaac463d1bcdb141a4ff4ff66.tar.gz linux-5b45bfe5010ae1ddaac463d1bcdb141a4ff4ff66.tar.bz2 linux-5b45bfe5010ae1ddaac463d1bcdb141a4ff4ff66.zip | |
wimax/i2400m: fix the bootmode RX deadlock in SDIO driver
i2400ms_bus_bm_wait_for_ack() causes a race condition. It happens
because this function clears i2400ms->bm_ack_size before waiting for
an interrupt, which is set by the interrupt service routine i2400ms_rx()
to indicate reception and size of received data; thus, if the interrupt
came right before the clearing/waiting, it is lost.
The fix is clear the bm_ack_size to -EINPROGRESS before we are enabling
the RX interrupt configuration in i2400ms_rx_setup(). Then everytime
when the interrupt service routine i2400ms_rx() is invoked during bootmode,
bm_ack_size is updated with the actual rx_size and it is cleared to
-EINPROGRESS again after the RX data is handled.
Signed-off-by: Cindy H Kao <cindy.h.kao@intel.com>
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/wimax/i2400m/sdio-fw.c | 8 | ||||
| -rw-r--r-- | drivers/net/wimax/i2400m/sdio-rx.c | 7 |
2 files changed, 11 insertions, 4 deletions
diff --git a/drivers/net/wimax/i2400m/sdio-fw.c b/drivers/net/wimax/i2400m/sdio-fw.c index 7d6ec0f475f8..c8dc538d40c1 100644 --- a/drivers/net/wimax/i2400m/sdio-fw.c +++ b/drivers/net/wimax/i2400m/sdio-fw.c @@ -177,10 +177,6 @@ ssize_t i2400ms_bus_bm_wait_for_ack(struct i2400m *i2400m, d_fnstart(5, dev, "(i2400m %p ack %p size %zu)\n", i2400m, ack, ack_size); - spin_lock(&i2400m->rx_lock); - i2400ms->bm_ack_size = -EINPROGRESS; - spin_unlock(&i2400m->rx_lock); - result = wait_event_timeout(i2400ms->bm_wfa_wq, i2400ms->bm_ack_size != -EINPROGRESS, 2 * HZ); @@ -199,6 +195,10 @@ ssize_t i2400ms_bus_bm_wait_for_ack(struct i2400m *i2400m, size = min(ack_size, i2400ms->bm_ack_size); memcpy(ack, i2400m->bm_ack_buf, size); } + /* + * Remember always to clear the bm_ack_size to -EINPROGRESS + * after the RX data is processed + */ i2400ms->bm_ack_size = -EINPROGRESS; spin_unlock(&i2400m->rx_lock); diff --git a/drivers/net/wimax/i2400m/sdio-rx.c b/drivers/net/wimax/i2400m/sdio-rx.c index 321beadf6e47..f6ca51ab216d 100644 --- a/drivers/net/wimax/i2400m/sdio-rx.c +++ b/drivers/net/wimax/i2400m/sdio-rx.c @@ -234,6 +234,13 @@ int i2400ms_rx_setup(struct i2400ms *i2400ms) init_waitqueue_head(&i2400ms->bm_wfa_wq); spin_lock(&i2400m->rx_lock); i2400ms->bm_wait_result = -EINPROGRESS; + /* + * Before we are about to enable the RX interrupt, make sure + * bm_ack_size is cleared to -EINPROGRESS which indicates + * no RX interrupt happened yet or the previous interrupt + * has been handled, we are ready to take the new interrupt + */ + i2400ms->bm_ack_size = -EINPROGRESS; spin_unlock(&i2400m->rx_lock); sdio_claim_host(func); |