Re: [Part2 PATCH v6 13/38] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

On Mon, Oct 23, 2017 at 02:57:04PM -0500, Brijesh Singh wrote:

Calling PLATFORM_GET_STATUS is not required, we can manage the state through
a simple ref count variable. Issuing PSP commands will always be much more
expensive compare to accessing a protected global variable.

What does "protected" mean here?

In any case, that variable can be a simple bool as you use it as such.

I would prefer to avoid invoking PSP command if possible.
Additionally, the global semaphore is still needed to serialize
the sev_platform_init() and sev_platform_shutdown() from multiple
processes. e.g If process "A" calls sev_platform_init() and if it gets
preempted due to whatever reason then we don't want another process
to issue the shutdown command while process "A" is in middle of
sev_platform_init().

How? You're holding fw_init_mutex.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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