In the Linux kernel, the following vulnerability has been resolved: serial: 8250: fix possible ISR soft lockup There are rare cases in which the host gets stuck in the ISR because it is flooded with messages during the startup phase. The reason for the soft lockup in the ISR is the missing FIFO error IRQ (FIFOE) handling. Not handling it and reporting IRQ_HANDLED triggers the IRQ immediately again. Fix this by adding a check for the FIFOE status and clearing the FIFO if no data is ready (DR). This behavior was observed on an AM62L device which uses the OMAP 8250 driver. Fix it for all 8250 drivers, since the OMAP driver's special IRQ setup handling may trigger this behavior more frequently, but it is not ensured that other 8250 drivers aren't affected.
https://git.kernel.org/stable/c/95d0b40c0623fd2b58c753f8dd6adda7263e3cd1
https://git.kernel.org/stable/c/8b67af8cd90542b2607623e3282811849e191b79
https://git.kernel.org/stable/c/4bce4a6f6318035d77d6b6199527b1950bb015f4
https://git.kernel.org/stable/c/4295c58990b7a84e8349a2226db692e252825b60
https://git.kernel.org/stable/c/2881b2e6da02daea1eb8254247ba8fd20c9d3348
https://git.kernel.org/stable/c/0c6bf45e5a345cc3b9ffbeaf9083ecac3c2293eb
https://git.kernel.org/stable/c/03ed804a0ddc3d069faf94c47f9e702afe5ca084