| Message ID | 20240205-cdns-qspi-pm-fix-v2-2-2e7bbad49a46@bootlin.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | spi: cadence-qspi: Fix runtime PM and system-wide suspend | expand |
Hello, On Wed Feb 7, 2024 at 9:42 AM CET, Dhruva Gole wrote: > On Feb 05, 2024 at 15:57:30 +0100, Théo Lebrun wrote: > > dev_get_drvdata() gets used to acquire the pointer to cqspi and the SPI > > controller. Neither embed the other; this lead to memory corruption. > > > > On a given platform (Mobileye EyeQ5) the memory corruption is hidden > > inside cqspi->f_pdata. Also, this uninitialised memory is used as a > > mutex (ctlr->bus_lock_mutex) by spi_controller_suspend(). > > > > Fixes: 2087e85bb66e ("spi: cadence-quadspi: fix suspend-resume implementations") > > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> > > --- > > drivers/spi/spi-cadence-quadspi.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c > > index 720b28d2980c..1a27987638f0 100644 > > --- a/drivers/spi/spi-cadence-quadspi.c > > +++ b/drivers/spi/spi-cadence-quadspi.c > > @@ -1930,10 +1930,9 @@ static void cqspi_remove(struct platform_device *pdev) > > static int cqspi_runtime_suspend(struct device *dev) > > { > > struct cqspi_st *cqspi = dev_get_drvdata(dev); > > - struct spi_controller *host = dev_get_drvdata(dev); > > Or you could do: > + struct spi_controller *host = cqspi->host; Indeed. I preferred minimizing line count as I didn't see a benefit to introducing a new variable. It goes away new patch anyway. If you prefer it this way tell me and I'll fix it for next revision. Thanks Dhruva, -- Théo Lebrun, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
On Wed, Feb 07, 2024 at 02:09:02PM +0530, Dhruva Gole wrote: > On Feb 05, 2024 at 15:12:10 +0000, Mark Brown wrote: > > Please place fixes at the start of serieses so that they don't end up > > with spurious dependencies on other changes and can more easily be > > applied as fixes. > Didn't really understand the comment here, aren't the 1,2 and 3 patches > fixes and the last one the non-fix? Thus fixes are indeed placed at > start of this series right? Patch 1 is a rename, this is obviously cosmetic and not a bug fix.
Hey, On Feb 07, 2024 at 09:50:16 +0000, Mark Brown wrote: > On Wed, Feb 07, 2024 at 02:09:02PM +0530, Dhruva Gole wrote: > > On Feb 05, 2024 at 15:12:10 +0000, Mark Brown wrote: > > > > Please place fixes at the start of serieses so that they don't end up > > > with spurious dependencies on other changes and can more easily be > > > applied as fixes. > > > Didn't really understand the comment here, aren't the 1,2 and 3 patches > > fixes and the last one the non-fix? Thus fixes are indeed placed at > > start of this series right? > > Patch 1 is a rename, this is obviously cosmetic and not a bug fix. Well, Theo, seems like you better fix the first patch, then reorder and send a v3 :)
diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c index 720b28d2980c..1a27987638f0 100644 --- a/drivers/spi/spi-cadence-quadspi.c +++ b/drivers/spi/spi-cadence-quadspi.c @@ -1930,10 +1930,9 @@ static void cqspi_remove(struct platform_device *pdev) static int cqspi_runtime_suspend(struct device *dev) { struct cqspi_st *cqspi = dev_get_drvdata(dev); - struct spi_controller *host = dev_get_drvdata(dev); int ret; - ret = spi_controller_suspend(host); + ret = spi_controller_suspend(cqspi->host); cqspi_controller_enable(cqspi, 0); clk_disable_unprepare(cqspi->clk); @@ -1944,7 +1943,6 @@ static int cqspi_runtime_suspend(struct device *dev) static int cqspi_runtime_resume(struct device *dev) { struct cqspi_st *cqspi = dev_get_drvdata(dev); - struct spi_controller *host = dev_get_drvdata(dev); clk_prepare_enable(cqspi->clk); cqspi_wait_idle(cqspi); @@ -1953,7 +1951,7 @@ static int cqspi_runtime_resume(struct device *dev) cqspi->current_cs = -1; cqspi->sclk = 0; - return spi_controller_resume(host); + return spi_controller_resume(cqspi->host); } static DEFINE_RUNTIME_DEV_PM_OPS(cqspi_dev_pm_ops, cqspi_runtime_suspend,
dev_get_drvdata() gets used to acquire the pointer to cqspi and the SPI controller. Neither embed the other; this lead to memory corruption. On a given platform (Mobileye EyeQ5) the memory corruption is hidden inside cqspi->f_pdata. Also, this uninitialised memory is used as a mutex (ctlr->bus_lock_mutex) by spi_controller_suspend(). Fixes: 2087e85bb66e ("spi: cadence-quadspi: fix suspend-resume implementations") Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> --- drivers/spi/spi-cadence-quadspi.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)