Re: TPM bug fix causes hang on suspend (2.6.35-rc4)

[Sarah Sharp <sarah.a.sharp@linux.intel.com>]

On Mon, Jul 19, 2010 at 10:05:41AM -0700, Sarah Sharp wrote:
> On Sat, Jul 17, 2010 at 04:12:23PM +0200, Thomas Meyer wrote:
> > Am Freitag, den 16.07.2010, 17:00 -0700 schrieb Sarah Sharp:
> > > I recently upgraded to 2.6.35-rc4, and I discovered that suspend no
> > > longer works on my Thinkpad x200s.  When I suspend with some programs
> > > open (specifically while buffy is reading my maildirs), the suspend
> > > light blinks forever and the system never suspends.
> > > 
> > > I bisected the issue down to commit b5edfef, which is a merge of James
> > > Morris' security-testing-2.6 tree, that only included this commit:
> > > 
> > > commit 02a077c52ef7631275a79862ffd9f3dbe9d38bc2
> > > Author: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
> > > Date:   Mon Jun 14 13:58:22 2010 -0300
> > > 
> > >     TPM: ReadPubEK output struct fix
> > >     
> > >     This patch adds a missing element of the ReadPubEK command output,
> > >     that prevents future overflow of this buffer when copying the
> > >     TPM output result into it.
> > >     
> > >     Prevents a kernel panic in case the user tries to read the
> > >     pubek from sysfs.
> > >     
> > >     Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
> > >     Signed-off-by: James Morris <jmorris@namei.org>
> > > 
> > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > > index 8e00b4d..792868d 100644
> > > --- a/drivers/char/tpm/tpm.h
> > > +++ b/drivers/char/tpm/tpm.h
> > > @@ -224,6 +224,7 @@ struct      tpm_readpubek_params_out {
> > >         u8      algorithm[4];
> > >         u8      encscheme[2];
> > >         u8      sigscheme[2];
> > > +       __be32  paramsize;
> > >         u8      parameters[12]; /*assuming RSA*/
> > >         __be32  keysize;
> > >         u8      modulus[256];
> > > 
> > > The dmesg captured over netconsole when suspend fails is attached, but
> > > it doesn't look very interesting.  lspci output is also attached.  I
> > > don't have any userspace programs installed that can use TPM, like
> > > trousers or libtspi1.
> > > 
> > > If I try just removing the tpm_tis, tpm_bios, and tpm modules before
> > > suspending, the suspend still fails.  If I recompile without TPM
> > > hardware support (CONFIG_TCG_TPM=n), suspend still fails.  However, if I
> > > also turn off the securityFS config option (CONFIG_SECURITYFS),
> > > suspend succeeds.
> > > 
> > > It looks like an odd commit to cause a suspend failure, but when I reset
> > > the git HEAD to the commit before the merge of this patch, and suspend
> > > works fine.  Can you fix this?
> > > 
> > > Sarah Sharp
> > 
> > Maybe same as https://bugzilla.kernel.org/show_bug.cgi?id=16256 ?
> 
> That doesn't look really similar.  The user found a different patch at
> fault, and they were also able to successfully suspend when the tpm_tis
> module was removed, but suspend still breaks for me in that case.
> Suspend breaks with that commit even when I don't compile any tpm
> modules at all.  But I'll try Helmut's fix[1] and let you know if it
> works.

I tried the fix, and all seemed well for a while.  Then suspend randomly
broken again.  I've tried to update to 2.6.35, but I have the same issue
(constant blinking suspend light and the suspend never completes).

Sarah Sharp