In the Linux kernel, the following vulnerability has been resolved: i2c: core: Run atomic i2c xfer when !preemptible Since bae1d3a05a8b, i2c transfers are non-atomic if preemption is disabled. However, non-atomic i2c transfers require preemption (e.g. in waitforcompletion() while waiting for the DMA). panic() calls preemptdisablenotrace() before calling emergencyrestart(). Therefore, if an i2c device is used for the restart, the xfer should be atomic. This avoids warnings like: [ 12.667612] WARNING: CPU: 1 PID: 1 at kernel/rcu/treeplugin.h:318 rcunotecontextswitch+0x33c/0x6b0 [ 12.676926] Voluntary context switch within RCU read-side critical section! ... [ 12.742376] scheduletimeout from waitforcompletiontimeout+0x90/0x114 [ 12.749179] waitforcompletiontimeout from tegrai2cwaitcompletion+0x40/0x70 ... [ 12.994527] atomicnotifiercallchain from machinerestart+0x34/0x58 [ 13.001050] machinerestart from panic+0x2a8/0x32c Use !preemptible() instead, which is basically the same check as pre-v5.2.