Messages in this thread | | | Date | Fri, 9 Oct 2015 13:58:12 +0300 | From | Jarkko Sakkinen <> | Subject | Re: [PATCH v3] tpm, tpm_crb: fix unaligned read of the command buffer address |
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Hi
This would desperately neeed Tested-by's (with Haswell PTT).
/Jarkko
On Tue, Sep 15, 2015 at 08:05:40PM +0300, Jarkko Sakkinen wrote: > The command buffer address must be read with exactly two 32-bit reads. > Otherwise, on some HW platforms, it seems that HW will abort the read > operation, which causes CPU to fill the read bytes with 1's. Therefore, > we cannot rely on memcpy_fromio() but must call ioread32() two times > instead. > > Also, this matches the PC Client Platform TPM Profile specification, > which defines command buffer address with two 32-bit fields. > > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > --- > drivers/char/tpm/tpm_crb.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c > index b4564b6..c09b370 100644 > --- a/drivers/char/tpm/tpm_crb.c > +++ b/drivers/char/tpm/tpm_crb.c > @@ -68,7 +68,8 @@ struct crb_control_area { > u32 int_enable; > u32 int_sts; > u32 cmd_size; > - u64 cmd_pa; > + u32 cmd_pa_low; > + u32 cmd_pa_high; > u32 rsp_size; > u64 rsp_pa; > } __packed; > @@ -263,8 +264,8 @@ static int crb_acpi_add(struct acpi_device *device) > return -ENOMEM; > } > > - memcpy_fromio(&pa, &priv->cca->cmd_pa, 8); > - pa = le64_to_cpu(pa); > + pa = ((u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_high)) << 32) + > + (u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_low)); > priv->cmd = devm_ioremap_nocache(dev, pa, > ioread32(&priv->cca->cmd_size)); > if (!priv->cmd) { > -- > 2.5.0 >
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