pci-ftpci100: race condition in masking/unmasking interrupts

From: Pali Rohár
Date: Wed Aug 18 2021 - 07:48:29 EST


I do not see any entry in MAINTAINERS file for pci-ftpci100.c driver, so
I'm not sure to whom should I address this issue...

During pci-aardvark review, Marc pointed one issue which is currently
available also in pci-ftpci100.c driver.

When masking or unmasking interrupts there is read-modify-write sequence
for FARADAY_PCI_CTRL2 register without any locking and is not atomic:


So there is race condition when masking/unmasking more interrupts at the
same time.