Description: x86/xen: Add some null pointer checking to smp.c
References:
Notes:
 carnil> First introducing commit could not be determined.
Bugs:
upstream: released (6.8-rc5) [3693bb4465e6e32a204a5b86d3ec7e6b9f7e67c2]
6.8-upstream-stable: N/A "Fixed before branching point"
6.7-upstream-stable: released (6.7.11) [d211e8128c0e2122512fa5e859316540349b54af]
6.6-upstream-stable: released (6.6.23) [a9bbb05c0c04b49a1f7f05fd03826321dca2b8d4]
6.1-upstream-stable: released (6.1.83) [f49c513f46dc19bf01ffad2aaaf234d7f37f6799]
5.10-upstream-stable: released (5.10.214) [eb279074badac0bbe28749906562d648ca4bc750]
4.19-upstream-stable: released (4.19.311) [70a33a629090130d731fc1e1ad498bb672eea165]
sid: released (6.7.12-1)
6.1-bookworm-security: released (6.1.85-1)
5.10-bullseye-security: needed
4.19-buster-security: needed