[PATCH] wfx: avoid flush_workqueue(system_highpri_wq) usage

Tetsuo Handa
2022-05-01T06:02:03Z

Flushing system-wide workqueues is dangerous and will be forbidden.
Replace system_highpri_wq with local wfx_wq.

While we are at it, add missing spi_unregister_driver() call when
sdio_register_driver() failed.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
---
Note: This patch is only compile tested.

drivers/net/wireless/silabs/wfx/bh.c | 6 +++---
drivers/net/wireless/silabs/wfx/hif_tx.c | 2 +-
drivers/net/wireless/silabs/wfx/main.c | 11 +++++++++++
drivers/net/wireless/silabs/wfx/wfx.h | 2 ++
4 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/silabs/wfx/bh.c b/drivers/net/wireless/silabs/wfx/bh.c
index bcea9d5b119c..377dd8b010e2 100644
--- a/drivers/net/wireless/silabs/wfx/bh.c
+++ b/drivers/net/wireless/silabs/wfx/bh.c
@@ -267,7 +267,7 @@ void wfx_bh_request_rx(struct wfx_dev *wdev)
wfx_control_reg_read(wdev, &cur);
prev = atomic_xchg(&wdev->hif.ctrl_reg, cur);
complete(&wdev->hif.ctrl_ready);
- queue_work(system_highpri_wq, &wdev->hif.bh);
+ queue_work(wfx_wq, &wdev->hif.bh);

if (!(cur & CTRL_NEXT_LEN_MASK))
dev_err(wdev->dev, "unexpected control register value: length field is 0: %04x\n",
@@ -280,7 +280,7 @@ void wfx_bh_request_rx(struct wfx_dev *wdev)
/* Driver want to send data */
void wfx_bh_request_tx(struct wfx_dev *wdev)
{
- queue_work(system_highpri_wq, &wdev->hif.bh);
+ queue_work(wfx_wq, &wdev->hif.bh);
}

/* If IRQ is not available, this function allow to manually poll the control register and simulate
@@ -295,7 +295,7 @@ void wfx_bh_poll_irq(struct wfx_dev *wdev)
u32 reg;

WARN(!wdev->poll_irq, "unexpected IRQ polling can mask IRQ");
- flush_workqueue(system_highpri_wq);
+ flush_workqueue(wfx_wq);
start = ktime_get();
for (;;) {
wfx_control_reg_read(wdev, &reg);
diff --git a/drivers/net/wireless/silabs/wfx/hif_tx.c b/drivers/net/wireless/silabs/wfx/hif_tx.c
index 9c653d0e9034..85c68b1b11c4 100644
--- a/drivers/net/wireless/silabs/wfx/hif_tx.c
+++ b/drivers/net/wireless/silabs/wfx/hif_tx.c
@@ -73,7 +73,7 @@ int wfx_cmd_send(struct wfx_dev *wdev, struct wfx_hif_msg *request,

if (no_reply) {
/* Chip won't reply. Ensure the wq has send the buffer before to continue. */
- flush_workqueue(system_highpri_wq);
+ flush_workqueue(wfx_wq);
ret = 0;
goto end;
}
diff --git a/drivers/net/wireless/silabs/wfx/main.c b/drivers/net/wireless/silabs/wfx/main.c
index e575a81ca2ca..d3d18c498dd0 100644
--- a/drivers/net/wireless/silabs/wfx/main.c
+++ b/drivers/net/wireless/silabs/wfx/main.c
@@ -40,6 +40,8 @@ MODULE_DESCRIPTION("Silicon Labs 802.11 Wireless LAN driver for WF200");
MODULE_AUTHOR("J辿r担me Pouiller <jerome.pouiller@silabs.com>");
MODULE_LICENSE("GPL");

+struct workqueue_struct *wfx_wq;
+
#define RATETAB_ENT(_rate, _rateid, _flags) { \
.bitrate = (_rate), \
.hw_value = (_rateid), \
@@ -473,10 +475,18 @@ static int __init wfx_core_init(void)
{
int ret = 0;

+ wfx_wq = alloc_workqueue("wfx_wq", WQ_HIGHPRI, 0);
+ if (!wfx_wq)
+ return -ENOMEM;
if (IS_ENABLED(CONFIG_SPI))
ret = spi_register_driver(&wfx_spi_driver);
if (IS_ENABLED(CONFIG_MMC) && !ret)
ret = sdio_register_driver(&wfx_sdio_driver);
+ if (ret) {
+ if (IS_ENABLED(CONFIG_SPI))
+ spi_unregister_driver(&wfx_spi_driver);
+ destroy_workqueue(wfx_wq);
+ }
return ret;
}
module_init(wfx_core_init);
@@ -487,5 +497,6 @@ static void __exit wfx_core_exit(void)
sdio_unregister_driver(&wfx_sdio_driver);
if (IS_ENABLED(CONFIG_SPI))
spi_unregister_driver(&wfx_spi_driver);
+ destroy_workqueue(wfx_wq);
}
module_exit(wfx_core_exit);
diff --git a/drivers/net/wireless/silabs/wfx/wfx.h b/drivers/net/wireless/silabs/wfx/wfx.h
index 6594cc647c2f..ea0ba002eb1f 100644
--- a/drivers/net/wireless/silabs/wfx/wfx.h
+++ b/drivers/net/wireless/silabs/wfx/wfx.h
@@ -159,4 +159,6 @@ static inline int memzcmp(void *src, unsigned int size)
return memcmp(buf, buf + 1, size - 1);
}

+extern struct workqueue_struct *wfx_wq;
+
#endif
--
2.34.1