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From: David Laight <David.Laight@ACULAB.COM>
To: =?Windows-1252?Q?=27Michal_Such=E1nek=27?= <msuchanek@suse.de>,
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Subject: RE: ibmvtpm byteswapping inconsistency
Thread-Topic: ibmvtpm byteswapping inconsistency
Thread-Index: AQHSeBIe8lHqrdS2Gkm+aOCXywnIf6FMLLKg
Date: Fri, 27 Jan 2017 11:18:01 +0000
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From: Michal Suchánek
> building ibmvtpm I noticed gcc warning complaining that second word of
> struct ibmvtpm_crq in tpm_ibmvtpm_suspend is uninitialized.
> 
> The structure is defined as
> 
> struct ibmvtpm_crq {
>         u8 valid;
>         u8 msg;
>         __be16 len;
>         __be32 data;
>         __be64 reserved;
> } __attribute__((packed, aligned(8)));
> 
> initialized as
> 
>         struct ibmvtpm_crq crq;
>         u64 *buf = (u64 *) &crq;
...

Hrummfff....
What is that attribute for, seems pretty confusing and pointless to me.

I also suspect that if you want to access it as two 64bit words it
ought to be a union.

	David