diff options
author | Sasha Levin <sashal@kernel.org> | 2020-06-15 17:28:08 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-06-20 10:23:17 +0200 |
commit | efc093e63fa85b1863d900642123f5b84a78a115 (patch) | |
tree | b0eada103b4f2a7ffaadc43cbe228df50b45d711 /drivers/spi | |
parent | 7a5764e8990096fd08e8566b87df3c111bf5a736 (diff) |
spi: dw: fix possible race condition
[ Upstream commit 66b19d762378785d1568b5650935205edfeb0503 ]
It is possible to get an interrupt as soon as it is requested. dw_spi_irq
does spi_controller_get_devdata(master) and expects it to be different than
NULL. However, spi_controller_set_devdata() is called after request_irq(),
resulting in the following crash:
CPU 0 Unable to handle kernel paging request at virtual address 00000030, epc == 8058e09c, ra == 8018ff90
[...]
Call Trace:
[<8058e09c>] dw_spi_irq+0x8/0x64
[<8018ff90>] __handle_irq_event_percpu+0x70/0x1d4
[<80190128>] handle_irq_event_percpu+0x34/0x8c
[<801901c4>] handle_irq_event+0x44/0x80
[<801951a8>] handle_level_irq+0xdc/0x194
[<8018f580>] generic_handle_irq+0x38/0x50
[<804c6924>] ocelot_irq_handler+0x104/0x1c0
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-dw.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 5688591e9cd3..61a951549eba 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -501,6 +501,8 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num); spin_lock_init(&dws->buf_lock); + spi_master_set_devdata(master, dws); + ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dws->name, master); if (ret < 0) { dev_err(dev, "can not get IRQ\n"); @@ -532,7 +534,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) } } - spi_master_set_devdata(master, dws); ret = devm_spi_register_master(dev, master); if (ret) { dev_err(&master->dev, "problem registering spi master\n"); |