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Instead of simply getting an -EBUSY, the > users will start seeing a hung task splats in dmesg. > > Also, since the last VM has to re-enable hotplug, you'll need a > up_read_non_owner() variant for cpus_read_unlock() to unlock the rwsem > from a different thread compared to the one that locks. > > I think cpu_hotplug_disable() is the correct way to go forward but if > you are not a fan of the global "snp_cpu_hotplug_disabled" flag, maybe > it can be turned into an indicator like "snp_initialized" in > "struct sev_device". Thoughts? > As i mentioned in my previous reply, i have already removed the global "snp_cpu_hotplug_disabled", the new implementation is flag-free, and does hotplug disable/enable by following the SNP_EN state. Thanks, Ashish