diff options
| author | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2018-07-17 16:23:10 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2018-07-18 13:21:33 +0100 |
| commit | 66b19d762378785d1568b5650935205edfeb0503 (patch) | |
| tree | 397e6a3f84beb9f367dba8f2705ac8cf63f86893 /drivers/spi | |
| parent | 2ba87a9bcc7a10aa28af9fbf5b4354b3168366e2 (diff) | |
| download | linux-66b19d762378785d1568b5650935205edfeb0503.tar.bz2 | |
spi: dw: fix possible race condition
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>
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 f693bfe95ab9..a087464efdd7 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -485,6 +485,8 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) dws->dma_inited = 0; dws->dma_addr = (dma_addr_t)(dws->paddr + DW_SPI_DR); + spi_controller_set_devdata(master, dws); + ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dev_name(dev), master); if (ret < 0) { @@ -518,7 +520,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) } } - spi_controller_set_devdata(master, dws); ret = devm_spi_register_controller(dev, master); if (ret) { dev_err(&master->dev, "problem registering spi master\n"); |