On Sun, 14 Jun 2020 at 13:57, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote: > > If interrupt comes late, during probe error path or device remove (could > be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler > dspi_interrupt() will access registers with the clock being disabled. This > leads to external abort on non-linefetch on Toradex Colibri VF50 module > (with Vybrid VF5xx): > > $ echo 4002d000.spi > /sys/devices/platform/soc/40000000.bus/4002d000.spi/driver/unbind > > Unhandled fault: external abort on non-linefetch (0x1008) at 0x8887f02c > Internal error: : 1008 [#1] ARM > CPU: 0 PID: 136 Comm: sh Not tainted 5.7.0-next-20200610-00009-g5c913fa0f9c5-dirty #74 > Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) > (regmap_mmio_read32le) from [<8061885c>] (regmap_mmio_read+0x48/0x68) > (regmap_mmio_read) from [<8060e3b8>] (_regmap_bus_reg_read+0x24/0x28) > (_regmap_bus_reg_read) from [<80611c50>] (_regmap_read+0x70/0x1c0) > (_regmap_read) from [<80611dec>] (regmap_read+0x4c/0x6c) > (regmap_read) from [<80678ca0>] (dspi_interrupt+0x3c/0xa8) > (dspi_interrupt) from [<8017acec>] (free_irq+0x26c/0x3cc) > (free_irq) from [<8017dcec>] (devm_irq_release+0x1c/0x20) > (devm_irq_release) from [<805f98ec>] (release_nodes+0x1e4/0x298) > (release_nodes) from [<805f9ac8>] (devres_release_all+0x40/0x60) > (devres_release_all) from [<805f5134>] (device_release_driver_internal+0x108/0x1ac) > (device_release_driver_internal) from [<805f521c>] (device_driver_detach+0x20/0x24) > > The resource-managed framework should not be used for interrupt handling, > because the resource will be released too late - after disabling clocks. > The interrupt handler is not prepared for such case. > > Fixes: 349ad66c0ab0 ("spi:Add Freescale DSPI driver for Vybrid VF610 platform") > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> > > --- I don't buy this argument that "the resource-managed framework should not be used for interrupt handling". What is it there for, then? Could you just call disable_irq before clk_disable_unprepare instead of this massive rework? > > This is an follow up of my other patch for I2C IMX driver [1]. Let's fix the > issues consistently. > > [1] https://lore.kernel.org/lkml/1592130544-19759-2-git-send-email-krzk@xxxxxxxxxx/T/#u > --- > drivers/spi/spi-fsl-dspi.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c > index 58190c94561f..57e7a626ba00 100644 > --- a/drivers/spi/spi-fsl-dspi.c > +++ b/drivers/spi/spi-fsl-dspi.c > @@ -1385,8 +1385,8 @@ static int dspi_probe(struct platform_device *pdev) > goto poll_mode; > } > > - ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, > - IRQF_SHARED, pdev->name, dspi); > + ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL, > + IRQF_SHARED, pdev->name, dspi); > if (ret < 0) { > dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n"); > goto out_clk_put; > @@ -1400,7 +1400,7 @@ static int dspi_probe(struct platform_device *pdev) > ret = dspi_request_dma(dspi, res->start); > if (ret < 0) { > dev_err(&pdev->dev, "can't get dma channels\n"); > - goto out_clk_put; > + goto out_free_irq; > } > } > > @@ -1415,11 +1415,14 @@ static int dspi_probe(struct platform_device *pdev) > ret = spi_register_controller(ctlr); > if (ret != 0) { > dev_err(&pdev->dev, "Problem registering DSPI ctlr\n"); > - goto out_clk_put; > + goto out_free_irq; > } > > return ret; > > +out_free_irq: > + if (dspi->irq > 0) > + free_irq(dspi->irq, dspi); > out_clk_put: > clk_disable_unprepare(dspi->clk); > out_ctlr_put: > @@ -1435,6 +1438,8 @@ static int dspi_remove(struct platform_device *pdev) > > /* Disconnect from the SPI framework */ > dspi_release_dma(dspi); > + if (dspi->irq > 0) > + free_irq(dspi->irq, dspi); > clk_disable_unprepare(dspi->clk); > spi_unregister_controller(dspi->ctlr); > > -- > 2.7.4 > Thanks, -Vladimir