In the Linux kernel, the following vulnerability has been resolved:
f2fs: don't set RO when shutting down f2fs
Shutdown does not check the error of thaw_super due to readonly, which causes a deadlock like below.
f2fsiocshutdown(F2FSGOINGDOWNFULLSYNC) issuediscardthread - bdevfreeze - freezesuper - f2fsstopcheckpoint() - f2fshandlecriticalerror - sbstartwrite - set RO - waiting - bdevthaw - thawsuperlocked - return -EINVAL, if sbrdonly() - f2fsstopdiscardthread -> wait for kthreadstop(discard_thread);