Comment 0 for bug 1830435

[Impact]
sysfs continues to expose a valid phy linkrate even after the phy has been disabled.

[Test Case]
Using hisi_sas, a libsas-based driver:
(initramfs) cd /sys/class/sas_phy/phy-0\:0\:20
(initramfs) cat negotiated_linkrate
12.0 Gbit
(initramfs) echo 0 > enable
[ 59.172411] hisi_sas_v3_hw 0000:74:02.0: phydown: phy0 phy_state=0xfe
[ 59.178851] hisi_sas_v3_hw 0000:74:02.0: erroneous completion iptt=4028 task=00000000bb3ab63f dev id=1 CQ hdr: 0x1103 0x10fbc 0x0 0x20000 Error info: 0x0 0x4000000 0x0 0x0
[ 59.194139] sas: smp_execute_task_sg: task to dev 500e004aaaaaaa1f response: 0x0 status 0x2
(initramfs) cat negotiated_linkrate
12.0 Gbit

[Regression Risk]
Impact is limited to drivers built on top of libsas.