CVE-2023-52791

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 wait_for_completion() while waiting
for the DMA). panic() calls preempt_disable_notrace() before calling
emergency_restart(). 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/tree_plugin.h:318
rcu_note_context_switch+0x33c/0x6b0 [ 12.676926] Voluntary context switch
within RCU read-side critical section! … [ 12.742376] schedule_timeout
from wait_for_completion_timeout+0x90/0x114 [ 12.749179]
wait_for_completion_timeout from tegra_i2c_wait_completion+0x40/0x70 … [
12.994527] atomic_notifier_call_chain from machine_restart+0x34/0x58 [
13.001050] machine_restart from panic+0x2a8/0x32c Use !preemptible()
instead, which is basically the same check as pre-v5.2.