When request firmware fails, brcmf_ops_sdio_remove is being called and
brcmf_bus freed. In such circumstancies if you do a suspend/resume cycle
the kernel hangs on resume due a NULL pointer dereference in resume
function.
Steps to reproduce the problem:
- modprobe brcmfmac without the firmware
brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac4354-sdio.bin
failed with error -2
- do a suspend/resume cycle (echo mem > /sys/power/state)
Protect against the NULL pointer derefence by checking if dev_get_drvdata
returned a valid pointer.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
---
I'm not sure about if this is the correct way to fix this but at least it
prevents the kernel to hang. From one side I'm not sure why suspend/resume
functions are called in such case and why the device is not removed from
the bus, from the other side I saw, that others drivers only unregisters
from sdio when the driver is removed so I supose this is the normal behavior.
Cheers,
Enric
drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
index 9b970dc..aa0e7c2 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
@@ -1274,14 +1274,16 @@ static int brcmf_ops_sdio_suspend(struct device *dev)
static int brcmf_ops_sdio_resume(struct device *dev)
{
struct brcmf_bus *bus_if = dev_get_drvdata(dev);
- struct brcmf_sdio_dev *sdiodev = bus_if->bus_priv.sdio;
struct sdio_func *func = container_of(dev, struct sdio_func, dev);
brcmf_dbg(SDIO, "Enter: F%d\n", func->num);
if (func->num != SDIO_FUNC_2)
return 0;
- brcmf_sdiod_freezer_off(sdiodev);
+ if (!bus_if)
+ return 0;
+
+ brcmf_sdiod_freezer_off(bus_if->bus_priv.sdio);
return 0;
}
@@ -1319,4 +1321,3 @@ void brcmf_sdio_exit(void)
sdio_unregister_driver(&brcmf_sdmmc_driver);
}
-
--
2.9.3
