[PATCH AUTOSEL for 4.14 107/135] vt6655: Fix a possible sleep-in-atomic bug in vt6655_suspend

From: alexander . levin
Date: Thu Dec 07 2017 - 12:52:16 EST


From: Jia-Ju Bai <baijiaju1990@xxxxxxx>

[ Upstream commit 42c8eb3f6e15367981b274cb79ee4657e2c6949d ]

The driver may sleep under a spinlock, and the function call path is:
vt6655_suspend (acquire the spinlock)
pci_set_power_state
__pci_start_power_transition (drivers/pci/pci.c)
msleep --> may sleep

To fix it, pci_set_power_state is called without having a spinlock.

This bug is found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/staging/vt6655/device_main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c
index 9fcf2e223f71..1123b4f1e1d6 100644
--- a/drivers/staging/vt6655/device_main.c
+++ b/drivers/staging/vt6655/device_main.c
@@ -1693,10 +1693,11 @@ static int vt6655_suspend(struct pci_dev *pcid, pm_message_t state)
MACbShutdown(priv);

pci_disable_device(pcid);
- pci_set_power_state(pcid, pci_choose_state(pcid, state));

spin_unlock_irqrestore(&priv->lock, flags);

+ pci_set_power_state(pcid, pci_choose_state(pcid, state));
+
return 0;
}

--
2.11.0