From 4033714d6cbe04893aa0708d1fcaa45dd8eb3f53 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Micha=C5=82=20Miros=C5=82aw?= Date: Tue, 11 Feb 2020 11:35:01 +0100 Subject: [PATCH] staging: wfx: fix init/remove vs IRQ race MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Current code races in init/exit with interrupt handlers. This is noticed by the warning below. Fix it by using devres for ordering allocations and IRQ de/registration. WARNING: CPU: 0 PID: 827 at drivers/staging/wfx/bus_spi.c:142 wfx_spi_irq_handler+0x5c/0x64 [wfx] race condition in driver init/deinit Cc: stable@vger.kernel.org Fixes: 0096214a59a7 ("staging: wfx: add support for I/O access") Signed-off-by: Michał Mirosław Reviewed-by: Jérôme Pouiller Link: https://lore.kernel.org/r/f0c66cbb3110c2736cd4357c753fba8c14ee3aee.1581416843.git.mirq-linux@rere.qmqm.pl Signed-off-by: Greg Kroah-Hartman --- drivers/staging/wfx/bus_sdio.c | 15 ++++++--------- drivers/staging/wfx/bus_spi.c | 27 ++++++++++++++------------- drivers/staging/wfx/main.c | 21 +++++++++++++-------- drivers/staging/wfx/main.h | 1 - 4 files changed, 33 insertions(+), 31 deletions(-) diff --git a/drivers/staging/wfx/bus_sdio.c b/drivers/staging/wfx/bus_sdio.c index f890116..5450bd5e 100644 --- a/drivers/staging/wfx/bus_sdio.c +++ b/drivers/staging/wfx/bus_sdio.c @@ -200,25 +200,23 @@ static int wfx_sdio_probe(struct sdio_func *func, if (ret) goto err0; - ret = wfx_sdio_irq_subscribe(bus); - if (ret) - goto err1; - bus->core = wfx_init_common(&func->dev, &wfx_sdio_pdata, &wfx_sdio_hwbus_ops, bus); if (!bus->core) { ret = -EIO; - goto err2; + goto err1; } + ret = wfx_sdio_irq_subscribe(bus); + if (ret) + goto err1; + ret = wfx_probe(bus->core); if (ret) - goto err3; + goto err2; return 0; -err3: - wfx_free_common(bus->core); err2: wfx_sdio_irq_unsubscribe(bus); err1: @@ -234,7 +232,6 @@ static void wfx_sdio_remove(struct sdio_func *func) struct wfx_sdio_priv *bus = sdio_get_drvdata(func); wfx_release(bus->core); - wfx_free_common(bus->core); wfx_sdio_irq_unsubscribe(bus); sdio_claim_host(func); sdio_disable_func(func); diff --git a/drivers/staging/wfx/bus_spi.c b/drivers/staging/wfx/bus_spi.c index 40bc330..605ad74 100644 --- a/drivers/staging/wfx/bus_spi.c +++ b/drivers/staging/wfx/bus_spi.c @@ -154,6 +154,11 @@ static void wfx_spi_request_rx(struct work_struct *work) wfx_bh_request_rx(bus->core); } +static void wfx_flush_irq_work(void *w) +{ + flush_work(w); +} + static size_t wfx_spi_align_size(void *priv, size_t size) { // Most of SPI controllers avoid DMA if buffer size is not 32bit aligned @@ -207,22 +212,23 @@ static int wfx_spi_probe(struct spi_device *func) udelay(2000); } - ret = devm_request_irq(&func->dev, func->irq, wfx_spi_irq_handler, - IRQF_TRIGGER_RISING, "wfx", bus); - if (ret) - return ret; - INIT_WORK(&bus->request_rx, wfx_spi_request_rx); bus->core = wfx_init_common(&func->dev, &wfx_spi_pdata, &wfx_spi_hwbus_ops, bus); if (!bus->core) return -EIO; - ret = wfx_probe(bus->core); + ret = devm_add_action_or_reset(&func->dev, wfx_flush_irq_work, + &bus->request_rx); if (ret) - wfx_free_common(bus->core); + return ret; - return ret; + ret = devm_request_irq(&func->dev, func->irq, wfx_spi_irq_handler, + IRQF_TRIGGER_RISING, "wfx", bus); + if (ret) + return ret; + + return wfx_probe(bus->core); } static int wfx_spi_remove(struct spi_device *func) @@ -230,11 +236,6 @@ static int wfx_spi_remove(struct spi_device *func) struct wfx_spi_priv *bus = spi_get_drvdata(func); wfx_release(bus->core); - wfx_free_common(bus->core); - // A few IRQ will be sent during device release. Hopefully, no IRQ - // should happen after wdev/wvif are released. - devm_free_irq(&func->dev, func->irq, bus); - flush_work(&bus->request_rx); return 0; } diff --git a/drivers/staging/wfx/main.c b/drivers/staging/wfx/main.c index 84adad6..76b2ff7 100644 --- a/drivers/staging/wfx/main.c +++ b/drivers/staging/wfx/main.c @@ -262,6 +262,16 @@ static int wfx_send_pdata_pds(struct wfx_dev *wdev) return ret; } +static void wfx_free_common(void *data) +{ + struct wfx_dev *wdev = data; + + mutex_destroy(&wdev->rx_stats_lock); + mutex_destroy(&wdev->conf_mutex); + wfx_tx_queues_deinit(wdev); + ieee80211_free_hw(wdev->hw); +} + struct wfx_dev *wfx_init_common(struct device *dev, const struct wfx_platform_data *pdata, const struct hwbus_ops *hwbus_ops, @@ -332,15 +342,10 @@ struct wfx_dev *wfx_init_common(struct device *dev, wfx_init_hif_cmd(&wdev->hif_cmd); wfx_tx_queues_init(wdev); - return wdev; -} + if (devm_add_action_or_reset(dev, wfx_free_common, wdev)) + return NULL; -void wfx_free_common(struct wfx_dev *wdev) -{ - mutex_destroy(&wdev->rx_stats_lock); - mutex_destroy(&wdev->conf_mutex); - wfx_tx_queues_deinit(wdev); - ieee80211_free_hw(wdev->hw); + return wdev; } int wfx_probe(struct wfx_dev *wdev) diff --git a/drivers/staging/wfx/main.h b/drivers/staging/wfx/main.h index 875f8c2..9c94100 100644 --- a/drivers/staging/wfx/main.h +++ b/drivers/staging/wfx/main.h @@ -34,7 +34,6 @@ struct wfx_dev *wfx_init_common(struct device *dev, const struct wfx_platform_data *pdata, const struct hwbus_ops *hwbus_ops, void *hwbus_priv); -void wfx_free_common(struct wfx_dev *wdev); int wfx_probe(struct wfx_dev *wdev); void wfx_release(struct wfx_dev *wdev); -- 2.7.4