Re: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute conversion

["Wang, Jian J" <jian.j.wang@intel.com>]

The NX Memory Protection and Heap Guard features need to clear paging attributes.
Allowing 0 attribute is the current only choice without changing arch protocol. Maybe
It's time to introduce a new protocol.

Regards,
Jian


> -----Original Message-----
> From: Zeng, Star
> Sent: Tuesday, April 03, 2018 9:16 AM
> To: Kinney, Michael D <michael.d.kinney@intel.com>; Heyi Guo
> <heyi.guo@linaro.org>; edk2-devel@lists.01.org
> Cc: Yi Li <phoenix.liyi@huawei.com>; Renhao Liang
> <liangrenhao@huawei.com>; Dong, Eric <eric.dong@intel.com>; Gao, Liming
> <liming.gao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>; Ni, Ruiyu
> <ruiyu.ni@intel.com>; Zeng, Star <star.zeng@intel.com>
> Subject: RE: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute conversion
> 
> Current gCpu->SetMemoryAttributes does not support getting memory
> attributes, and has no clear description about clearing memory attributes.
> 
> I noticed we introduced
> SmmMemoryAttribute(MdeModulePkg\Include\Protocol\SmmMemoryAttribute.
> h) protocol for heap guard feature in SMM environment.
> Seemingly, we also need introduce MemoryAttribute protocol for DXE?
> 
> 
> Thanks,
> Star
> -----Original Message-----
> From: Zeng, Star
> Sent: Tuesday, April 3, 2018 8:59 AM
> To: Kinney, Michael D <michael.d.kinney@intel.com>; Heyi Guo
> <heyi.guo@linaro.org>; edk2-devel@lists.01.org
> Cc: Yi Li <phoenix.liyi@huawei.com>; Renhao Liang
> <liangrenhao@huawei.com>; Dong, Eric <eric.dong@intel.com>; Gao, Liming
> <liming.gao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>; Ni, Ruiyu
> <ruiyu.ni@intel.com>; Zeng, Star <star.zeng@intel.com>
> Subject: RE: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute conversion
> 
> Mike,
> 
> Agree the problem.
> We need support only RUNTIME attribute.
> We need support only cache attributes.
> We need support only page attributes.
> We need support RUNTIME + cache + page attributes.
> Do we need support the 0 Attributes case to clear page attributes?
> There was discussion about the 0 Attributes case at
> https://lists.01.org/pipermail/edk2-devel/2018-March/023315.html.
> It came to the question that should the 0 Attributes case be handled by
> SetMemoryAttributes() to clear the page attributes?
> 
> 
> Thanks,
> Star
> -----Original Message-----
> From: Kinney, Michael D
> Sent: Tuesday, April 3, 2018 5:43 AM
> To: Zeng, Star <star.zeng@intel.com>; Heyi Guo <heyi.guo@linaro.org>; edk2-
> devel@lists.01.org; Kinney, Michael D <michael.d.kinney@intel.com>
> Cc: Yi Li <phoenix.liyi@huawei.com>; Renhao Liang
> <liangrenhao@huawei.com>; Dong, Eric <eric.dong@intel.com>; Gao, Liming
> <liming.gao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>; Ni, Ruiyu
> <ruiyu.ni@intel.com>
> Subject: RE: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute conversion
> 
> Star,
> 
> This commit breaks Vlv2TbltDevicePkg.
> 
> On this platform, there are 2 calls to
> gDS->SetMemorySpaceAttributes() for an MMIO
> range to set only the EFI_MEMORY_RUNTIME bit.
> 
> With this commit, ConverToCpuArchAttributes()returns 0, and 0 is passed to
> gCpu->SetMemoryAttributes()that returns EFI_INVALID_PARAMETER on
> Vlv2TbltDevicePkg.
> 
> Before this commit, ConverToCpuArchAttributes() returns
> INVALID_CPU_ARCH_ATTRIBUTES which causes the call to gCpu-
> >SetMemoryAttributes()to be skipped so no error is generated.
> 
> I think the right fix is to skip the call to
> gCpu->SetMemoryAttributes() if CpuArchAttributes
> is 0 so a call that only sets the RUNTIME attribute can be supported along with
> call the set both the RUNTIME bit and other cache related bits.
> 
> I will send a patch soon with the proposed fix.
> 
> Mike
> 
> > -----Original Message-----
> > From: Zeng, Star
> > Sent: Sunday, April 1, 2018 10:59 PM
> > To: Heyi Guo <heyi.guo@linaro.org>; edk2- devel@lists.01.org
> > Cc: Yi Li <phoenix.liyi@huawei.com>; Renhao Liang
> > <liangrenhao@huawei.com>; Dong, Eric <eric.dong@intel.com>; Kinney,
> > Michael D <michael.d.kinney@intel.com>; Gao, Liming
> > <liming.gao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>; Ni,
> > Ruiyu <ruiyu.ni@intel.com>; Zeng, Star <star.zeng@intel.com>
> > Subject: RE: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute
> > conversion
> >
> > Pushed at 5b91bf82c67b586b9588cbe4bbffa1588f6b5926.
> >
> > Thanks,
> > Star
> > -----Original Message-----
> > From: Heyi Guo [mailto:heyi.guo@linaro.org]
> > Sent: Thursday, March 29, 2018 4:20 PM
> > To: edk2-devel@lists.01.org
> > Cc: Heyi Guo <heyi.guo@linaro.org>; Yi Li <phoenix.liyi@huawei.com>;
> > Renhao Liang <liangrenhao@huawei.com>; Zeng, Star
> > <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>; Kinney,
> > Michael D <michael.d.kinney@intel.com>; Gao, Liming
> > <liming.gao@intel.com>; Wang, Jian J <jian.j.wang@intel.com>; Ni,
> > Ruiyu <ruiyu.ni@intel.com>
> > Subject: [PATCH 1/1] MdeModulePkg/Gcd: Fix bug of attribute conversion
> >
> > For gDS->SetMemorySpaceAttributes(), when user passes a combined
> > memory attribute including CPU arch attribute and other attributes,
> > like EFI_MEMORY_RUNTIME,
> > ConverToCpuArchAttributes() will return INVALID_CPU_ARCH_ATTRIBUTES
> > and skip setting page/cache attribute for the specified memory space.
> >
> > We don't see any reason to forbid combining CPU arch attributes and
> > non-CPU-arch attributes when calling gDS-
> > >SetMemorySpaceAttributes(), so we remove the check code
> > in ConverToCpuArchAttributes(); the remaining code is enough to grab
> > the interested bits for
> > Cpu->SetMemoryAttributes().
> >
> > Contributed-under: TianoCore Contribution Agreement 1.1
> > Signed-off-by: Heyi Guo <heyi.guo@linaro.org>
> > Signed-off-by: Yi Li <phoenix.liyi@huawei.com>
> > Signed-off-by: Renhao Liang <liangrenhao@huawei.com>
> > Cc: Star Zeng <star.zeng@intel.com>
> > Cc: Eric Dong <eric.dong@intel.com>
> > Cc: Michael D Kinney <michael.d.kinney@intel.com>
> > Cc: Liming Gao <liming.gao@intel.com>
> > Cc: Jian J Wang <jian.j.wang@intel.com>
> > Cc: Ruiyu Ni <ruiyu.ni@intel.com>
> > ---
> >  MdeModulePkg/Core/Dxe/Gcd/Gcd.c | 5 -----
> >  1 file changed, 5 deletions(-)
> >
> > diff --git a/MdeModulePkg/Core/Dxe/Gcd/Gcd.c
> > b/MdeModulePkg/Core/Dxe/Gcd/Gcd.c index
> > 77f4adb4bc01..907245a3f512 100644
> > --- a/MdeModulePkg/Core/Dxe/Gcd/Gcd.c
> > +++ b/MdeModulePkg/Core/Dxe/Gcd/Gcd.c
> > @@ -673,11 +673,6 @@ ConverToCpuArchAttributes (  {
> >    UINT64      CpuArchAttributes;
> >
> > -  if ((Attributes & ~(EXCLUSIVE_MEMORY_ATTRIBUTES |
> > -                      NONEXCLUSIVE_MEMORY_ATTRIBUTES))
> > != 0) {
> > -    return INVALID_CPU_ARCH_ATTRIBUTES;
> > -  }
> > -
> >    CpuArchAttributes = Attributes &
> > NONEXCLUSIVE_MEMORY_ATTRIBUTES;
> >
> >    if ( (Attributes & EFI_MEMORY_UC) == EFI_MEMORY_UC) {
> > --
> > 2.7.4