Patch set 2 has been submitted for review.

Thanks
Ashish
________________________________
From: Wu, Hao A <hao.a...@intel.com>
Sent: Thursday, October 10, 2019 11:53 PM
To: devel@edk2.groups.io <devel@edk2.groups.io>; Ashish Singhal 
<ashishsin...@nvidia.com>; Ni, Ray <ray...@intel.com>
Subject: RE: [edk2-devel] [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page 
Allocation


Hello Ashish,



I think the IOMMU feature is added for the protection of FW integrity against

HW devices, which is the motivation to use IOMMU PPI for memory allocation.



The fix is easy for the DXE part since the IOMMU part has been integrated to the

implementation of the PciIo protocol.



As for the XhciPei case, my thought is that a new helper function (maybe called

'IoMmuAllocateAlignedBuffer') can be added in DmaMem.c file. The main differece

between IoMmuAllocateAlignedBuffer() and existing IoMmuAllocateBuffer() will be:



1. If IOMMU PPI exists, mIoMmu->AllocateBuffer() should be called with bigger

number of pages for alignment and mIoMmu->FreeBuffer() can be called right after

to free the unused pages.



2. If IOMMU PPI does not exist, this case will fall back to a similar fix for

the DXE case.



Ideally, IoMmuFreeBuffer() can be reused to free the aligned buffer.

Please help to raise if you observe any open for the above proposal, thanks.



Best Regards,

Hao Wu



From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of Ashish 
Singhal
Sent: Friday, October 11, 2019 11:30 AM
To: Wu, Hao A; devel@edk2.groups.io; Ni, Ray
Subject: Re: [edk2-devel] [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page 
Allocation



Hello Hao,



What is your motivation towards using IoMMUPei for memory allocation now 
instead of Pei Services? The fix would be simple if we just change the number 
of pages needed to accommodate for the alignment. The call to free the pages 
would not do anything.



If we use IoMMUPei, we may need to change function definition for allocate to 
return how many pages were allocated for each call so that freeing can be done 
correctly as well. This may need more refactoring of the code that initially 
thought of.



Thanks

Ashish



From: Wu, Hao A <hao.a...@intel.com>
Sent: Thursday, October 10, 2019 9:00 PM
To: devel@edk2.groups.io; Ashish Singhal <ashishsin...@nvidia.com>; Ni, Ray 
<ray...@intel.com>
Subject: RE: [edk2-devel] [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page 
Allocation



Thanks Ashish,



Please help to send out the fix for XhciPei in a separate patch as well.

I can help to see if verification can be done on my side.



Best Regards,

Hao Wu



From: devel@edk2.groups.io<mailto:devel@edk2.groups.io> 
[mailto:devel@edk2.groups.io] On Behalf Of Ashish Singhal
Sent: Friday, October 11, 2019 1:51 AM
To: Wu, Hao A; devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Ni, Ray
Subject: Re: [edk2-devel] [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page 
Allocation



Hello Hao,



I agree that for completeness we should fix the issue in both DXE as well as 
PEI but on my target, we do not have any PEI phase for me to be able to verify 
any change that I will be making. If you still want, I can still make the 
change so that someone else can verify or we can have someone else fix PEI and 
push my change meanwhile to fix the issue in DXE.



Thanks

Ashish

________________________________

From: Wu, Hao A <hao.a...@intel.com<mailto:hao.a...@intel.com>>
Sent: Wednesday, October 9, 2019 8:09 PM
To: Ashish Singhal <ashishsin...@nvidia.com<mailto:ashishsin...@nvidia.com>>; 
devel@edk2.groups.io<mailto:devel@edk2.groups.io> 
<devel@edk2.groups.io<mailto:devel@edk2.groups.io>>; Ni, Ray 
<ray...@intel.com<mailto:ray...@intel.com>>
Subject: RE: [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page Allocation



> -----Original Message-----
> From: Ashish Singhal [mailto:ashishsin...@nvidia.com]
> Sent: Thursday, October 10, 2019 9:58 AM
> To: Wu, Hao A; devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Ni, Ray
> Subject: RE: [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page Allocation
>
> Hello Hao,
>
> I can see that the PEI also has the same issue and take a look at that as well
> but I have no way to verify that as we are not using it. For the change I have
> made in DXE, I have verified it with an alignment of 4K and 64K.


Is it possible for you to verify the PEI case with a test PEI module that
performs read operation to a USB storage device? I think this will trigger
the affecting codes.

In my opinion, it would be better for the fix to be complete.

Best Regards,
Hao Wu


>
> Thanks
> Ashish
>
> -----Original Message-----
> From: Wu, Hao A <hao.a...@intel.com<mailto:hao.a...@intel.com>>
> Sent: Wednesday, October 9, 2019 7:33 PM
> To: Ashish Singhal <ashishsin...@nvidia.com<mailto:ashishsin...@nvidia.com>>; 
> devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Ni,
> Ray <ray...@intel.com<mailto:ray...@intel.com>>
> Subject: RE: [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page Allocation
>
> > -----Original Message-----
> > From: Ashish Singhal [mailto:ashishsin...@nvidia.com]
> > Sent: Thursday, October 10, 2019 1:02 AM
> > To: devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Wu, Hao A; Ni, Ray
> > Cc: Ashish Singhal
> > Subject: [PATCH] MdeModulePkg/XhciDxe: Fix Aligned Page Allocation
> >
> > While allocating pages aligned at an alignment higher than 4K,
> > allocate memory taking into consideration the padding required for
> > that alignment. The calls to free pages takes care of this already.
> >
> > Signed-off-by: Ashish Singhal 
> > <ashishsin...@nvidia.com<mailto:ashishsin...@nvidia.com>>
> > ---
> >  MdeModulePkg/Bus/Pci/XhciDxe/UsbHcMem.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/UsbHcMem.c
> > b/MdeModulePkg/Bus/Pci/XhciDxe/UsbHcMem.c
> > index fd79988..aa69c47 100644
> > --- a/MdeModulePkg/Bus/Pci/XhciDxe/UsbHcMem.c
> > +++ b/MdeModulePkg/Bus/Pci/XhciDxe/UsbHcMem.c
> > @@ -656,7 +656,7 @@ UsbHcAllocateAlignedPages (
> >                        PciIo,
> >                        AllocateAnyPages,
> >                        EfiBootServicesData,
> > -                      Pages,
> > +                      RealPages,
> >                        &Memory,
> >                        0
> >                        );
>
>
> Hello,
>
> The change looks good to me.
>
> Just a couple of things to confirm:
>
> 1. I think there is a similar case within the XhciPei driver Could you help to
> resolve it as well?
>
> I think for the PEI counterpart you may need to update both
> UsbHcAllocateAlignedPages() and UsbHcFreeAlignedPages(), since the
> IOMMU helper functions like IoMmuAllocateBuffer() and IoMmuFreeBuffer()
> might not be suitable now. Instead, I think services in the IoMmu PPI can be
> used.
>
> 2. Could you help to provide the information on what test has been done for
> the proposed patch?
>
> Thanks in advance.
>
> Best Regards,
> Hao Wu
>
>
> > --
> > 2.7.4
>
> -----------------------------------------------------------------------------------
> This email message is for the sole use of the intended recipient(s) and may
> contain
> confidential information.  Any unauthorized review, use, disclosure or
> distribution
> is prohibited.  If you are not the intended recipient, please contact the
> sender by
> reply email and destroy all copies of the original message.
> -----------------------------------------------------------------------------------



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#48849): https://edk2.groups.io/g/devel/message/48849
Mute This Topic: https://groups.io/mt/34465466/21656
Group Owner: devel+ow...@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub  [arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-

Reply via email to