From c7299fea67696db5bd09d924d1f1080d894f92ef Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Mon, 26 Apr 2021 16:56:38 -0700 Subject: [PATCH 1/4] spi: Fix spi device unregister flow When an SPI device is unregistered, the spi->controller->cleanup() is called in the device's release callback. That's wrong for a couple of reasons: 1. spi_dev_put() can be called before spi_add_device() is called. And it's spi_add_device() that calls spi_setup(). This will cause clean() to get called without the spi device ever being setup. 2. There's no guarantee that the controller's driver would be present by the time the spi device's release function gets called. 3. It also causes "sleeping in atomic context" stack dump[1] when device link deletion code does a put_device() on the spi device. Fix these issues by simply moving the cleanup from the device release callback to the actual spi_unregister_device() function. [1] - https://lore.kernel.org/lkml/CAHp75Vc=FCGcUyS0v6fnxme2YJ+qD+Y-hQDQLa2JhWNON9VmsQ@mail.gmail.com/ Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20210426235638.1285530-1-saravanak@google.com Signed-off-by: Mark Brown --- drivers/spi/spi.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ba425b9c7700..f9885c096563 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -47,10 +47,6 @@ static void spidev_release(struct device *dev) { struct spi_device *spi = to_spi_device(dev); - /* spi controllers may cleanup for released devices */ - if (spi->controller->cleanup) - spi->controller->cleanup(spi); - spi_controller_put(spi->controller); kfree(spi->driver_override); kfree(spi); @@ -558,6 +554,12 @@ static int spi_dev_check(struct device *dev, void *data) return 0; } +static void spi_cleanup(struct spi_device *spi) +{ + if (spi->controller->cleanup) + spi->controller->cleanup(spi); +} + /** * spi_add_device - Add spi_device allocated with spi_alloc_device * @spi: spi_device to register @@ -622,11 +624,13 @@ int spi_add_device(struct spi_device *spi) /* Device may be bound to an active driver when this returns */ status = device_add(&spi->dev); - if (status < 0) + if (status < 0) { dev_err(dev, "can't add %s, status %d\n", dev_name(&spi->dev), status); - else + spi_cleanup(spi); + } else { dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); + } done: mutex_unlock(&spi_add_lock); @@ -710,6 +714,8 @@ void spi_unregister_device(struct spi_device *spi) if (!spi) return; + spi_cleanup(spi); + if (spi->dev.of_node) { of_node_clear_flag(spi->dev.of_node, OF_POPULATED); of_node_put(spi->dev.of_node); From 41f48a29ebd5ce944e412f491f1876b5abeff1d6 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Tue, 27 Apr 2021 16:38:42 +0200 Subject: [PATCH 2/4] spi: altera: Make SPI_ALTERA_CORE invisible The SPI_ALTERA_CORE config symbol controls compilation of the Altera SPI Controller core code. It is already selected by all of its users, so there is no reason to make it visible, unless compile-testing. Fixes: b0c3d9354de1f87e ("spi: altera: separate core code from platform code") Signed-off-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/f0cb8e66baba4506db6f42fca74dc51b76883507.1619534253.git.geert+renesas@glider.be Signed-off-by: Mark Brown --- drivers/spi/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 8b161ec4943b..f4481fe48bf0 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -65,7 +65,7 @@ config SPI_ALTERA This is the driver for the Altera SPI Controller. config SPI_ALTERA_CORE - tristate "Altera SPI Controller core code" + tristate "Altera SPI Controller core code" if COMPILE_TEST select REGMAP help "The core code for the Altera SPI Controller" From 121271f08809e5dc01d15d3e529988ac5d740af6 Mon Sep 17 00:00:00 2001 From: Amit Kumar Mahapatra Date: Wed, 28 Apr 2021 23:38:01 -0600 Subject: [PATCH 3/4] spi: spi-zynq-qspi: Fix kernel-doc warning Fix kernel-doc warning. Signed-off-by: Amit Kumar Mahapatra Link: https://lore.kernel.org/r/20210429053802.17650-2-amit.kumar-mahapatra@xilinx.com Signed-off-by: Mark Brown --- drivers/spi/spi-zynq-qspi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-zynq-qspi.c b/drivers/spi/spi-zynq-qspi.c index 5d8a5ee62fa2..1acde9e24973 100644 --- a/drivers/spi/spi-zynq-qspi.c +++ b/drivers/spi/spi-zynq-qspi.c @@ -367,7 +367,7 @@ static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi) } /** - * zynq_qspi_setup - Configure the QSPI controller + * zynq_qspi_setup_op - Configure the QSPI controller * @spi: Pointer to the spi_device structure * * Sets the operational mode of QSPI controller for the next QSPI transfer, baud From 6d5ff8e632a4f2389c331e5554cd1c2a9a28c7aa Mon Sep 17 00:00:00 2001 From: Karen Dombroski Date: Wed, 28 Apr 2021 23:38:02 -0600 Subject: [PATCH 4/4] spi: spi-zynq-qspi: Fix stack violation bug When the number of bytes for the op is greater than one, the read could run off the end of the function stack and cause a crash. This patch restores the behaviour of safely reading out of the original opcode location. Signed-off-by: Karen Dombroski Signed-off-by: Amit Kumar Mahapatra Link: https://lore.kernel.org/r/20210429053802.17650-3-amit.kumar-mahapatra@xilinx.com Signed-off-by: Mark Brown --- drivers/spi/spi-zynq-qspi.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-zynq-qspi.c b/drivers/spi/spi-zynq-qspi.c index 1acde9e24973..5a3d81c31d04 100644 --- a/drivers/spi/spi-zynq-qspi.c +++ b/drivers/spi/spi-zynq-qspi.c @@ -528,18 +528,17 @@ static int zynq_qspi_exec_mem_op(struct spi_mem *mem, struct zynq_qspi *xqspi = spi_controller_get_devdata(mem->spi->master); int err = 0, i; u8 *tmpbuf; - u8 opcode = op->cmd.opcode; dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n", - opcode, op->cmd.buswidth, op->addr.buswidth, + op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, op->dummy.buswidth, op->data.buswidth); zynq_qspi_chipselect(mem->spi, true); zynq_qspi_config_op(xqspi, mem->spi); - if (op->cmd.nbytes) { + if (op->cmd.opcode) { reinit_completion(&xqspi->data_completion); - xqspi->txbuf = &opcode; + xqspi->txbuf = (u8 *)&op->cmd.opcode; xqspi->rxbuf = NULL; xqspi->tx_bytes = op->cmd.nbytes; xqspi->rx_bytes = op->cmd.nbytes;