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From: David Laight <David.Laight@ACULAB.COM>
To: "'Michal Suchánek'" <msuchanek@suse.de>,
	"Ashley Lai" <ashleydlai@gmail.com>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
	"Paul Mackerras" <paulus@samba.org>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Peter Huewe" <peterhuewe@gmx.de>,
	"Marcel Selhorst" <tpmdd@selhorst.net>,
	"Jarkko Sakkinen" <jarkko.sakkinen@linux.intel.com>,
	"Jason Gunthorpe" <jgunthorpe@obsidianresearch.com>,
	"tpmdd-devel@lists.sourceforge.net"
	<tpmdd-devel@lists.sourceforge.net>,
	"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: ibmvtpm byteswapping inconsistency
Date: Fri, 27 Jan 2017 11:18:01 +0000	[thread overview]
Message-ID: <063D6719AE5E284EB5DD2968C1650D6DB0270A32@AcuExch.aculab.com> (raw)
In-Reply-To: <20170126212248.3f3e9103@kitsune.suse.cz>

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

      parent reply	other threads:[~2017-01-27 11:40 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-26 20:22 ibmvtpm byteswapping inconsistency Michal Suchánek
2017-01-26 22:05 ` Jason Gunthorpe
2017-01-26 22:43   ` Michal Suchanek
2017-01-26 22:58   ` Ashley Lai
2017-02-02  4:40     ` Vicky
2017-02-02 10:55       ` Michael Ellerman
2017-02-02 11:29       ` Michal Suchánek
2017-02-02 15:17         ` David Laight
2017-01-27  1:42 ` Tyrel Datwyler
2017-01-27  1:50   ` Benjamin Herrenschmidt
2017-01-27  9:03     ` Michal Suchanek
2017-01-27 21:19       ` Tyrel Datwyler
2017-01-30  4:32         ` Michael Ellerman
2017-01-30 20:34           ` Tyrel Datwyler
2017-01-31  8:38             ` Michael Ellerman
2017-01-27 18:02     ` Tyrel Datwyler
2017-01-27 19:58       ` Benjamin Herrenschmidt
2017-01-27 20:32         ` Tyrel Datwyler
2017-01-28  0:35           ` msuchanek
2017-01-28  4:28           ` Benjamin Herrenschmidt
2017-01-30 14:42       ` David Laight
2017-01-27 11:18 ` David Laight [this message]

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