diff mbox series

[V2] PCI: dwc: Fix n_fts[] array overrun

Message ID 20220926111923.22487-1-vidyas@nvidia.com (mailing list archive)
State Accepted
Delegated to: Lorenzo Pieralisi
Headers show
Series [V2] PCI: dwc: Fix n_fts[] array overrun | expand

Commit Message

Vidya Sagar Sept. 26, 2022, 11:19 a.m. UTC
commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
incorrectly uses pci->link_gen in deriving the index to the
n_fts[] array also introducing the issue of accessing beyond the
boundaries of array for greater than Gen-2 speeds. This change fixes
that issue.

Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
---
V2:
* Addressed review comments from Bjorn
* Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"

 drivers/pci/controller/dwc/pcie-designware.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Han Jingoo Sept. 29, 2022, 2:04 a.m. UTC | #1
On Mon, Sep 26, 2022, Vidya Sagar <vidyas@nvidia.com> wrote:
>
> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
> incorrectly uses pci->link_gen in deriving the index to the
> n_fts[] array also introducing the issue of accessing beyond the
> boundaries of array for greater than Gen-2 speeds. This change fixes
> that issue.

Dear Vidya,

I am just ok with this patch. By the way, do we need another patch to generalize
this setting? Currently, this code targets only Gen1 and Gen2. But, in
my opinion,
it is possible that this driver can be  used for more than Gen2,
later. PCIe Gen6
standard is available and Synopsys has their solution for Gen6. So, would you
send a new patch to generalize this thing, later?
Thank you.

Best regards,
Jingoo Han

>
> Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> Acked-by: Jingoo Han <jingoohan1@gmail.com>
> ---
> V2:
> * Addressed review comments from Bjorn
> * Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"
>
>  drivers/pci/controller/dwc/pcie-designware.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index 650a7f22f9d0..3df687667f27 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -649,7 +649,7 @@ void dw_pcie_setup(struct dw_pcie *pci)
>         if (pci->n_fts[1]) {
>                 val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
>                 val &= ~PORT_LOGIC_N_FTS_MASK;
> -               val |= pci->n_fts[pci->link_gen - 1];
> +               val |= pci->n_fts[1];
>                 dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
>         }
>
> --
> 2.17.1
>
Vidya Sagar Sept. 29, 2022, 4:57 a.m. UTC | #2
On 9/29/2022 7:34 AM, Han Jingoo wrote:
> External email: Use caution opening links or attachments
> 
> 
> On Mon, Sep 26, 2022, Vidya Sagar <vidyas@nvidia.com> wrote:
>>
>> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
>> incorrectly uses pci->link_gen in deriving the index to the
>> n_fts[] array also introducing the issue of accessing beyond the
>> boundaries of array for greater than Gen-2 speeds. This change fixes
>> that issue.
> 
> Dear Vidya,
> 
> I am just ok with this patch. By the way, do we need another patch to generalize
> this setting? Currently, this code targets only Gen1 and Gen2. But, in
> my opinion,
> it is possible that this driver can be  used for more than Gen2,
> later. PCIe Gen6
> standard is available and Synopsys has their solution for Gen6. So, would you
> send a new patch to generalize this thing, later?
> Thank you.

As I mentioned in the commit message, current code is incorrectly using 
'gen' in the index and ideally n_fts programming has nothing to do with 
the speed and hence I tried to remove the 'gen' reference in the current 
patch. So, the same code (after applying this patch) should work for any 
future Synopsys IP versions supporting higher speeds.

Thanks,
Vidya Sagar

> 
> Best regards,
> Jingoo Han
> 
>>
>> Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
>> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
>> Acked-by: Jingoo Han <jingoohan1@gmail.com>
>> ---
>> V2:
>> * Addressed review comments from Bjorn
>> * Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"
>>
>>   drivers/pci/controller/dwc/pcie-designware.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
>> index 650a7f22f9d0..3df687667f27 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware.c
>> +++ b/drivers/pci/controller/dwc/pcie-designware.c
>> @@ -649,7 +649,7 @@ void dw_pcie_setup(struct dw_pcie *pci)
>>          if (pci->n_fts[1]) {
>>                  val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
>>                  val &= ~PORT_LOGIC_N_FTS_MASK;
>> -               val |= pci->n_fts[pci->link_gen - 1];
>> +               val |= pci->n_fts[1];
>>                  dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
>>          }
>>
>> --
>> 2.17.1
>>
Han Jingoo Sept. 29, 2022, 4:49 p.m. UTC | #3
On Wed, Sep 28, 2022 Vidya Sagar <vidyas@nvidia.com> wrote:

> On 9/29/2022 7:34 AM, Han Jingoo wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On Mon, Sep 26, 2022, Vidya Sagar <vidyas@nvidia.com> wrote:
> >>
> >> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
> >> incorrectly uses pci->link_gen in deriving the index to the
> >> n_fts[] array also introducing the issue of accessing beyond the
> >> boundaries of array for greater than Gen-2 speeds. This change fixes
> >> that issue.
> >
> > Dear Vidya,
> >
> > I am just ok with this patch. By the way, do we need another patch to generalize
> > this setting? Currently, this code targets only Gen1 and Gen2. But, in
> > my opinion,
> > it is possible that this driver can be  used for more than Gen2,
> > later. PCIe Gen6
> > standard is available and Synopsys has their solution for Gen6. So, would you
> > send a new patch to generalize this thing, later?
> > Thank you.
>
> As I mentioned in the commit message, current code is incorrectly using
> 'gen' in the index and ideally n_fts programming has nothing to do with
> the speed and hence I tried to remove the 'gen' reference in the current
> patch. So, the same code (after applying this patch) should work for any
> future Synopsys IP versions supporting higher speeds.

I see. Thank you for your confirmation.

Best regards,
Jingoo Han

>
> Thanks,
> Vidya Sagar
>
> >
> > Best regards,
> > Jingoo Han
> >
> >>
> >> Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
> >> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> >> Acked-by: Jingoo Han <jingoohan1@gmail.com>
> >> ---
> >> V2:
> >> * Addressed review comments from Bjorn
> >> * Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"
> >>
> >>   drivers/pci/controller/dwc/pcie-designware.c | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> >> index 650a7f22f9d0..3df687667f27 100644
> >> --- a/drivers/pci/controller/dwc/pcie-designware.c
> >> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> >> @@ -649,7 +649,7 @@ void dw_pcie_setup(struct dw_pcie *pci)
> >>          if (pci->n_fts[1]) {
> >>                  val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
> >>                  val &= ~PORT_LOGIC_N_FTS_MASK;
> >> -               val |= pci->n_fts[pci->link_gen - 1];
> >> +               val |= pci->n_fts[1];
> >>                  dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
> >>          }
> >>
> >> --
> >> 2.17.1
> >>
Rob Herring Oct. 4, 2022, 9:50 p.m. UTC | #4
On Mon, Sep 26, 2022 at 6:19 AM Vidya Sagar <vidyas@nvidia.com> wrote:
>
> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
> incorrectly uses pci->link_gen in deriving the index to the
> n_fts[] array also introducing the issue of accessing beyond the
> boundaries of array for greater than Gen-2 speeds. This change fixes
> that issue.
>
> Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> Acked-by: Jingoo Han <jingoohan1@gmail.com>
> ---
> V2:
> * Addressed review comments from Bjorn
> * Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"
>
>  drivers/pci/controller/dwc/pcie-designware.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Rob Herring <robh@kernel.org>
Vidya Sagar Oct. 10, 2022, 5:51 a.m. UTC | #5
Hi Lorenzo,
Do you have any further comments for this patch?

Thanks,
Vidya Sagar

On 10/5/2022 3:20 AM, Rob Herring wrote:
> External email: Use caution opening links or attachments
> 
> 
> On Mon, Sep 26, 2022 at 6:19 AM Vidya Sagar <vidyas@nvidia.com> wrote:
>>
>> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
>> incorrectly uses pci->link_gen in deriving the index to the
>> n_fts[] array also introducing the issue of accessing beyond the
>> boundaries of array for greater than Gen-2 speeds. This change fixes
>> that issue.
>>
>> Fixes: aeaa0bfe8965 ("PCI: dwc: Move N_FTS setup to common setup")
>> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
>> Acked-by: Jingoo Han <jingoohan1@gmail.com>
>> ---
>> V2:
>> * Addressed review comments from Bjorn
>> * Added "Acked-by: Jingoo Han <jingoohan1@gmail.com>"
>>
>>   drivers/pci/controller/dwc/pcie-designware.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Reviewed-by: Rob Herring <robh@kernel.org>
>
Lorenzo Pieralisi Oct. 27, 2022, 8:15 a.m. UTC | #6
On Mon, 26 Sep 2022 16:49:23 +0530, Vidya Sagar wrote:
> commit aeaa0bfe89654 ("PCI: dwc: Move N_FTS setup to common setup")
> incorrectly uses pci->link_gen in deriving the index to the
> n_fts[] array also introducing the issue of accessing beyond the
> boundaries of array for greater than Gen-2 speeds. This change fixes
> that issue.
> 
> 
> [...]

Applied to pci/dwc, thanks!

[1/1] PCI: dwc: Fix n_fts[] array overrun
      https://git.kernel.org/lpieralisi/pci/c/66110361281b

Thanks,
Lorenzo
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 650a7f22f9d0..3df687667f27 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -649,7 +649,7 @@  void dw_pcie_setup(struct dw_pcie *pci)
 	if (pci->n_fts[1]) {
 		val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
 		val &= ~PORT_LOGIC_N_FTS_MASK;
-		val |= pci->n_fts[pci->link_gen - 1];
+		val |= pci->n_fts[1];
 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
 	}