PCI: aardvark: Don't rely on jiffies while holding spinlock

stable inclusion
from stable-v4.19.198
commit 6571c80330ac43f2487403f04efcdbbcf796cf7b
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9R4IP
CVE: CVE-2021-47229

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6571c80330ac43f2487403f04efcdbbcf796cf7b



---------------------------

commit 7fbcb5da upstream.

advk_pcie_wait_pio() can be called while holding a spinlock (from
pci_bus_read_config_dword()), then depends on jiffies in order to
timeout while polling on PIO state registers. In the case the PIO
transaction failed, the timeout will never happen and will also cause
the cpu to stall.

This decrements a variable and wait instead of using jiffies.

Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zeng Heng <zengheng4@huawei.com>