On Sun, Jun 14, 2020 at 12:29:04PM +0200, Krzysztof Kozlowski wrote:
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
Changes since v1:
- Remove the devm- and use regular methods.
Hi everyone,
Similar patch for SPI driver was already merged [1]. Any comments here?
Best regards, Krzysztof
[1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?...
drivers/i2c/busses/i2c-imx.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-)