CVE-2023-53712

In the Linux kernel, the following vulnerability has been resolved:

ARM: 9317/1: kexec: Make smp stop calls asynchronous

If a panic is triggered by a hrtimer interrupt all online cpus will be notified and set offline. But as highlighted by commit 19dbdcb8039c ("smp: Warn on function calls from softirq context") this call should not be made synchronous with disabled interrupts:

softdog: Initiating panic Kernel panic - not syncing: Software Watchdog Timer expired WARNING: CPU: 1 PID: 0 at kernel/smp.c:753 smpcallfunctionmanycond unwindbacktrace: showstack dumpstacklvl __warn warnslowpathfmt smp_callfunctionmanycond smpcallfunction crashsmpsendstop.part.0 machinecrashshutdown __crashkexec panic softdogfire _hrtimerrunqueues hrtimerinterrupt

Make the smp call for machinecrashnonpanic_core() asynchronous.