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* [PATCH v3] x86, tboot: iomem fixes
@ 2013-07-18  8:07 Qiaowei Ren
  2013-07-18 10:42 ` Ingo Molnar
  0 siblings, 1 reply; 4+ messages in thread
From: Qiaowei Ren @ 2013-07-18  8:07 UTC (permalink / raw)
  To: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86
  Cc: linux-kernel, Gang Wei, Qiaowei Ren

Current code doesn't use specific interface to access I/O space.
So some potential bugs can be caused. We can fix this by using
specific API.

Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
---
 arch/x86/kernel/tboot.c |   21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index 3ff42d2..afe8cf8 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -466,9 +466,12 @@ struct sinit_mle_data {
 	u32               vtd_dmars_off;
 } __packed;
 
+#define SINIT_MLE_DATA_VTD_DMAR_OFF	140
+
 struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
 {
-	void *heap_base, *heap_ptr, *config;
+	void __iomem *heap_base, *heap_ptr, *config;
+	u32 dmar_tbl_off;
 
 	if (!tboot_enabled())
 		return dmar_tbl;
@@ -485,25 +488,25 @@ struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
 		return NULL;
 
 	/* now map TXT heap */
-	heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
-			    *(u64 *)(config + TXTCR_HEAP_SIZE));
+	heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
+			    readl(config + TXTCR_HEAP_SIZE));
 	iounmap(config);
 	if (!heap_base)
 		return NULL;
 
 	/* walk heap to SinitMleData */
 	/* skip BiosData */
-	heap_ptr = heap_base + *(u64 *)heap_base;
+	heap_ptr = heap_base + readq(heap_base);
 	/* skip OsMleData */
-	heap_ptr += *(u64 *)heap_ptr;
+	heap_ptr += readq(heap_ptr);
 	/* skip OsSinitData */
-	heap_ptr += *(u64 *)heap_ptr;
+	heap_ptr += readq(heap_ptr);
 	/* now points to SinitMleDataSize; set to SinitMleData */
 	heap_ptr += sizeof(u64);
 	/* get addr of DMAR table */
-	dmar_tbl = (struct acpi_table_header *)(heap_ptr +
-		   ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
-		   sizeof(u64));
+	dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
+	memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
+			sizeof(struct acpi_table_header));
 
 	/* don't unmap heap because dmar.c needs access to this */
 
-- 
1.7.9.5


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH v3] x86, tboot: iomem fixes
  2013-07-18  8:07 [PATCH v3] x86, tboot: iomem fixes Qiaowei Ren
@ 2013-07-18 10:42 ` Ingo Molnar
  2013-07-18 12:42   ` Ren, Qiaowei
  0 siblings, 1 reply; 4+ messages in thread
From: Ingo Molnar @ 2013-07-18 10:42 UTC (permalink / raw)
  To: Qiaowei Ren
  Cc: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, linux-kernel,
	Gang Wei


* Qiaowei Ren <qiaowei.ren@intel.com> wrote:

> Current code doesn't use specific interface to access I/O space.
> So some potential bugs can be caused. We can fix this by using
> specific API.

This is still very vague.

> 
> Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
> ---
>  arch/x86/kernel/tboot.c |   21 ++++++++++++---------
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
> index 3ff42d2..afe8cf8 100644
> --- a/arch/x86/kernel/tboot.c
> +++ b/arch/x86/kernel/tboot.c
> @@ -466,9 +466,12 @@ struct sinit_mle_data {
>  	u32               vtd_dmars_off;
>  } __packed;
>  
> +#define SINIT_MLE_DATA_VTD_DMAR_OFF	140
> +
>  struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
>  {
> -	void *heap_base, *heap_ptr, *config;
> +	void __iomem *heap_base, *heap_ptr, *config;
> +	u32 dmar_tbl_off;
>  
>  	if (!tboot_enabled())
>  		return dmar_tbl;
> @@ -485,25 +488,25 @@ struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
>  		return NULL;
>  
>  	/* now map TXT heap */
> -	heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
> -			    *(u64 *)(config + TXTCR_HEAP_SIZE));
> +	heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
> +			    readl(config + TXTCR_HEAP_SIZE));
>  	iounmap(config);
>  	if (!heap_base)
>  		return NULL;
>  
>  	/* walk heap to SinitMleData */
>  	/* skip BiosData */
> -	heap_ptr = heap_base + *(u64 *)heap_base;
> +	heap_ptr = heap_base + readq(heap_base);
>  	/* skip OsMleData */
> -	heap_ptr += *(u64 *)heap_ptr;
> +	heap_ptr += readq(heap_ptr);
>  	/* skip OsSinitData */
> -	heap_ptr += *(u64 *)heap_ptr;
> +	heap_ptr += readq(heap_ptr);
>  	/* now points to SinitMleDataSize; set to SinitMleData */
>  	heap_ptr += sizeof(u64);
>  	/* get addr of DMAR table */
> -	dmar_tbl = (struct acpi_table_header *)(heap_ptr +
> -		   ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
> -		   sizeof(u64));
> +	dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
> +	memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
> +			sizeof(struct acpi_table_header));

That memcpy (or an equivalent of it) was not in the code before, AFAICS.

How can this be an 'interface fix'? It adds in new code...

Thanks,

	Ingo

^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: [PATCH v3] x86, tboot: iomem fixes
  2013-07-18 10:42 ` Ingo Molnar
@ 2013-07-18 12:42   ` Ren, Qiaowei
  2013-07-19  7:59     ` Ingo Molnar
  0 siblings, 1 reply; 4+ messages in thread
From: Ren, Qiaowei @ 2013-07-18 12:42 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86@kernel.org,
	linux-kernel@vger.kernel.org, Wei, Gang

On 2013-07-18, Ingo Molnar wrote:
> 
> * Qiaowei Ren <qiaowei.ren@intel.com> wrote:
> 
>> Current code doesn't use specific interface to access I/O space.
>> So some potential bugs can be caused. We can fix this by using
>> specific API.
> 
> This is still very vague.
> 
>> 
>> Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
>> ---
>>  arch/x86/kernel/tboot.c |   21 ++++++++++++---------
>>  1 file changed, 12 insertions(+), 9 deletions(-)
>> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index
>> 3ff42d2..afe8cf8 100644
>> --- a/arch/x86/kernel/tboot.c
>> +++ b/arch/x86/kernel/tboot.c
>> @@ -466,9 +466,12 @@ struct sinit_mle_data {
>>  	u32               vtd_dmars_off;
>>  } __packed;
>> +#define SINIT_MLE_DATA_VTD_DMAR_OFF	140
>> +
>>  struct acpi_table_header *tboot_get_dmar_table(struct
>> acpi_table_header *dmar_tbl)  {
>> -	void *heap_base, *heap_ptr, *config;
>> +	void __iomem *heap_base, *heap_ptr, *config;
>> +	u32 dmar_tbl_off;
>> 
>>  	if (!tboot_enabled())
>>  		return dmar_tbl;
>> @@ -485,25 +488,25 @@ struct acpi_table_header
> *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
>>  		return NULL;
>>  
>>  	/* now map TXT heap */
>> -	heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
>> -			    *(u64 *)(config + TXTCR_HEAP_SIZE));
>> +	heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
>> +			    readl(config + TXTCR_HEAP_SIZE));
>>  	iounmap(config);
>>  	if (!heap_base)
>>  		return NULL;
>>  
>>  	/* walk heap to SinitMleData */
>>  	/* skip BiosData */
>> -	heap_ptr = heap_base + *(u64 *)heap_base;
>> +	heap_ptr = heap_base + readq(heap_base);
>>  	/* skip OsMleData */
>> -	heap_ptr += *(u64 *)heap_ptr;
>> +	heap_ptr += readq(heap_ptr);
>>  	/* skip OsSinitData */
>> -	heap_ptr += *(u64 *)heap_ptr;
>> +	heap_ptr += readq(heap_ptr);
>>  	/* now points to SinitMleDataSize; set to SinitMleData */
>>  	heap_ptr += sizeof(u64);
>>  	/* get addr of DMAR table */
>> -	dmar_tbl = (struct acpi_table_header *)(heap_ptr +
>> -		   ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
>> -		   sizeof(u64));
>> +	dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
>> +	memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
>> +			sizeof(struct acpi_table_header));
> 
> That memcpy (or an equivalent of it) was not in the code before, AFAICS.
> 
> How can this be an 'interface fix'? It adds in new code...
> 
Sorry, current code only need to get addr of DMAR table, so memcpy_fromio may be removed, even though this will also work.
So "memcpy_fromio" line will be changed to 
	dmar_tbl = (struct acpi_table_header *)(heap_ptr + dmar_tbl_off + - sizeof(u64));
If so, no new interface will be added, and the changelog at the beginning of this patch is engouch?

Thanks,
Qiaowei


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3] x86, tboot: iomem fixes
  2013-07-18 12:42   ` Ren, Qiaowei
@ 2013-07-19  7:59     ` Ingo Molnar
  0 siblings, 0 replies; 4+ messages in thread
From: Ingo Molnar @ 2013-07-19  7:59 UTC (permalink / raw)
  To: Ren, Qiaowei
  Cc: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86@kernel.org,
	linux-kernel@vger.kernel.org, Wei, Gang


* Ren, Qiaowei <qiaowei.ren@intel.com> wrote:

> On 2013-07-18, Ingo Molnar wrote:
> > 
> > * Qiaowei Ren <qiaowei.ren@intel.com> wrote:
> > 
> >> Current code doesn't use specific interface to access I/O space.
> >> So some potential bugs can be caused. We can fix this by using
> >> specific API.
> > 
> > This is still very vague.
> > 
> >> 
> >> Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
> >> ---
> >>  arch/x86/kernel/tboot.c |   21 ++++++++++++---------
> >>  1 file changed, 12 insertions(+), 9 deletions(-)
> >> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index
> >> 3ff42d2..afe8cf8 100644
> >> --- a/arch/x86/kernel/tboot.c
> >> +++ b/arch/x86/kernel/tboot.c
> >> @@ -466,9 +466,12 @@ struct sinit_mle_data {
> >>  	u32               vtd_dmars_off;
> >>  } __packed;
> >> +#define SINIT_MLE_DATA_VTD_DMAR_OFF	140
> >> +
> >>  struct acpi_table_header *tboot_get_dmar_table(struct
> >> acpi_table_header *dmar_tbl)  {
> >> -	void *heap_base, *heap_ptr, *config;
> >> +	void __iomem *heap_base, *heap_ptr, *config;
> >> +	u32 dmar_tbl_off;
> >> 
> >>  	if (!tboot_enabled())
> >>  		return dmar_tbl;
> >> @@ -485,25 +488,25 @@ struct acpi_table_header
> > *tboot_get_dmar_table(struct acpi_table_header *dmar_tb
> >>  		return NULL;
> >>  
> >>  	/* now map TXT heap */
> >> -	heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
> >> -			    *(u64 *)(config + TXTCR_HEAP_SIZE));
> >> +	heap_base = ioremap(readl(config + TXTCR_HEAP_BASE),
> >> +			    readl(config + TXTCR_HEAP_SIZE));
> >>  	iounmap(config);
> >>  	if (!heap_base)
> >>  		return NULL;
> >>  
> >>  	/* walk heap to SinitMleData */
> >>  	/* skip BiosData */
> >> -	heap_ptr = heap_base + *(u64 *)heap_base;
> >> +	heap_ptr = heap_base + readq(heap_base);
> >>  	/* skip OsMleData */
> >> -	heap_ptr += *(u64 *)heap_ptr;
> >> +	heap_ptr += readq(heap_ptr);
> >>  	/* skip OsSinitData */
> >> -	heap_ptr += *(u64 *)heap_ptr;
> >> +	heap_ptr += readq(heap_ptr);
> >>  	/* now points to SinitMleDataSize; set to SinitMleData */
> >>  	heap_ptr += sizeof(u64);
> >>  	/* get addr of DMAR table */
> >> -	dmar_tbl = (struct acpi_table_header *)(heap_ptr +
> >> -		   ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
> >> -		   sizeof(u64));
> >> +	dmar_tbl_off = readl(heap_ptr + SINIT_MLE_DATA_VTD_DMAR_OFF);
> >> +	memcpy_fromio(dmar_tbl, heap_ptr + dmar_tbl_off - sizeof(u64),
> >> +			sizeof(struct acpi_table_header));
> > 
> > That memcpy (or an equivalent of it) was not in the code before, AFAICS.
> > 
> > How can this be an 'interface fix'? It adds in new code...
> > 
> Sorry, current code only need to get addr of DMAR table, so memcpy_fromio may be removed, even though this will also work.
> So "memcpy_fromio" line will be changed to 
> 	dmar_tbl = (struct acpi_table_header *)(heap_ptr + dmar_tbl_off + - sizeof(u64));
> If so, no new interface will be added, and the changelog at the beginning of this patch is engouch?

Please resubmit the fixed patch so I can have a fresh look.

Thanks,

	Ingo

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2013-07-19  7:59 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2013-07-18  8:07 [PATCH v3] x86, tboot: iomem fixes Qiaowei Ren
2013-07-18 10:42 ` Ingo Molnar
2013-07-18 12:42   ` Ren, Qiaowei
2013-07-19  7:59     ` Ingo Molnar

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