Description: blk-mq race condition
References:
 https://source.android.com/security/bulletin/pixel/2020-09-01
 https://android.googlesource.com/kernel/common/+/f530afb974c2
 https://android.googlesource.com/kernel/common/+/d4d74449367e
 https://android.googlesource.com/kernel/common/+/6754baabb890
Notes:
Bugs:
upstream: released (4.19-rc6) [f5bbbbe4d63577026f908a809f22f5fd5a90ea1f, 530ca2c9bd6949c72c9b5cfc330cb3dbccaa3f5b]
4.19-upstream-stable: N/A "Fixed before branching point"
4.9-upstream-stable: released (4.9.228) [f530afb974c2e82047bd6220303a2dbe30eff304, 6754baabb890eed09f30c84016242c52a6c2d2d4, d4d74449367e1ca68078db17dedd764916740cca]
sid: released (4.19.9-1)
4.19-buster-security: N/A "Fixed before branching point"
4.9-stretch-security: released (4.9.228-1)