From: Krzysztof Kozlowski krzk@kernel.org
commit e50e4f0b85be308a01b830c5fbdffc657e1a6dd0 upstream
If interrupt comes late, during probe error path or device remove (could be triggered with CONFIG_DEBUG_SHIRQ), the interrupt handler i2c_imx_isr() will access registers with the clock being disabled. This leads to external abort on non-linefetch on Toradex Colibri VF50 module (with Vybrid VF5xx):
Unhandled fault: external abort on non-linefetch (0x1008) at 0x8882d003 Internal error: : 1008 [#1] ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 5.7.0 #607 Hardware name: Freescale Vybrid VF5xx/VF6xx (Device Tree) (i2c_imx_isr) from [<8017009c>] (free_irq+0x25c/0x3b0) (free_irq) from [<805844ec>] (release_nodes+0x178/0x284) (release_nodes) from [<80580030>] (really_probe+0x10c/0x348) (really_probe) from [<80580380>] (driver_probe_device+0x60/0x170) (driver_probe_device) from [<80580630>] (device_driver_attach+0x58/0x60) (device_driver_attach) from [<805806bc>] (__driver_attach+0x84/0xc0) (__driver_attach) from [<8057e228>] (bus_for_each_dev+0x68/0xb4) (bus_for_each_dev) from [<8057f3ec>] (bus_add_driver+0x144/0x1ec) (bus_add_driver) from [<80581320>] (driver_register+0x78/0x110) (driver_register) from [<8010213c>] (do_one_initcall+0xa8/0x2f4) (do_one_initcall) from [<80c0100c>] (kernel_init_freeable+0x178/0x1dc) (kernel_init_freeable) from [<80807048>] (kernel_init+0x8/0x110) (kernel_init) from [<80100114>] (ret_from_fork+0x14/0x20)
Additionally, the i2c_imx_isr() could wake up the wait queue (imx_i2c_struct->queue) before its initialization happens.
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: 1c4b6c3bcf30 ("i2c: imx: implement bus recovery") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski krzk@kernel.org Acked-by: Oleksij Rempel o.rempel@pengutronix.de Signed-off-by: Wolfram Sang wsa@kernel.org [sudip: manual backport with extra label for goto] Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/busses/i2c-imx.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-)
--- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -1093,20 +1093,20 @@ static int i2c_imx_probe(struct platform goto clk_disable; }
- /* Request IRQ */ - ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0, - pdev->name, i2c_imx); - if (ret) { - dev_err(&pdev->dev, "can't claim irq %d\n", irq); - goto clk_disable; - } - /* Init queue */ init_waitqueue_head(&i2c_imx->queue);
/* Set up adapter data */ i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
+ /* Request IRQ */ + ret = request_threaded_irq(irq, i2c_imx_isr, NULL, 0, + pdev->name, i2c_imx); + if (ret) { + dev_err(&pdev->dev, "can't claim irq %d\n", irq); + goto clk_disable; + } + /* Set up clock divider */ i2c_imx->bitrate = IMX_I2C_BIT_RATE; ret = of_property_read_u32(pdev->dev.of_node, @@ -1125,7 +1125,7 @@ static int i2c_imx_probe(struct platform ret = i2c_add_numbered_adapter(&i2c_imx->adapter); if (ret < 0) { dev_err(&pdev->dev, "registration failed\n"); - goto clk_disable; + goto clk_free_irq; }
/* Set up platform driver data */ @@ -1143,6 +1143,8 @@ static int i2c_imx_probe(struct platform
return 0; /* Return OK */
+clk_free_irq: + free_irq(irq, i2c_imx); clk_disable: clk_disable_unprepare(i2c_imx->clk); return ret; @@ -1151,6 +1153,7 @@ clk_disable: static int i2c_imx_remove(struct platform_device *pdev) { struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); + int irq;
/* remove adapter */ dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); @@ -1165,6 +1168,10 @@ static int i2c_imx_remove(struct platfor imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
+ irq = platform_get_irq(pdev, 0); + if (irq >= 0) + free_irq(irq, i2c_imx); + return 0; }