Re: [PATCH 1/1] MdeModulePkg: fix !x86 builds (more)

["Leif Lindholm" <leif.lindholm@linaro.org>]

+Bob, Liming,

On Tue, Aug 27, 2019 at 09:26:05PM +0200, Laszlo Ersek wrote:
> Hi Leif,
> 
> On 08/27/19 14:43, Leif Lindholm wrote:
> > Commit 4a1f6b85c184
> > ("MdeModulePkg: add LockBoxNullLib for !IA32/X64 in .dsc")
> > added an ARM/AARCH64 resolution for LockBoxLib. However, this failed
> > to address the overrides provided for PEIM, DXE_DRIVER,
> > DXE_RUNTIME_DRIVER, DXE_SMM_DRIVER and UEFI_DRIVER, so any modules
> > of those classes still failed to build.
> >
> > Break these out properly into their own LibraryClasses sections.
> >
> > Resolves BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2134
> >
> > Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
> > Reported-by: Baptiste Gerondeau <baptiste.gerondeau@linaro.org>
> > Cc: Jian J Wang <jian.j.wang@intel.com>
> > Cc: Hao A Wu <hao.a.wu@intel.com>
> > ---
> >
> > I don't understand how the above would appear to work back when I
> > submitted the previous patch but not work now, but I haven't dug
> > into it deeper. Including the x86-specific LockBoxLib in the
> > .common section is however clearly not correct.
> 
> I agree with you that the present situation is not correct.
> 
> According to:
> 
>   https://edk2-docs.gitbooks.io/edk-ii-dsc-specification/2_dsc_overview/26_[libraryclasses]_section_processing.html
> 
> the library class resolutions take effect in the following order
> (entries near the top have higher priority):
> 
> > 1. <LibraryClasses> associated with the INF file in the [Components] section
> > 2. [LibraryClasses.$(Arch).$(MODULE_TYPE), LibraryClasses.$(Arch).$(MODULE_TYPE)]
> > 3. [LibraryClasses.$(Arch).$(MODULE_TYPE)]
> > 4. [LibraryClasses.common.$(MODULE_TYPE)]
> > 5. [LibraryClasses.$(Arch)]
> > 6. [LibraryClasses.common] or [LibraryClasses]
> 
> (Side comment 1: levels #2 and #3 look very similar; I think the
> difference is that #2 is supposed to be a multi-arch and/or
> multi-module-type section, while #3 is a single-arch and
> single-module-type section.)
> 
> Commit 4a1f6b85c184 ("MdeModulePkg: add LockBoxNullLib for !IA32/X64 in
> .dsc", 2019-03-27) provided a LockBoxLib resolution at level #5:

Yes.

> > [LibraryClasses.ARM, LibraryClasses.AARCH64]
> 
> However, the other LockBoxLib resolutions are at level #4:
> 
> > [LibraryClasses.common.PEIM]
> > [LibraryClasses.common.DXE_DRIVER]
> > [LibraryClasses.common.DXE_RUNTIME_DRIVER]
> > [LibraryClasses.common.DXE_SMM_DRIVER]
> > [LibraryClasses.common.UEFI_DRIVER]
> 
> So the latter taking priority is actually specified behavior.

Hmm. That's not great.
Anyway, I stopped being lazy and did a bisect.

The culprit is
e8449e1d8e3b ("BaseTools: Decouple AutoGen Objects"), marked as
resolving https://bugzilla.tianocore.org/show_bug.cgi?id=1875.

This also affects SignedCapsulePkg/SignedCapsulePkg.dsc (although once
addressed, AARCH64 also needs a NULL entry added for
CompilerIntrinsicsLib.

> (Side comment 2: EBC is in the same boat, from commit cbcccd2c9d93
> ("Update Code to pass EBC compiler", 2013-05-13):
> 
> > [LibraryClasses.EBC]
> >   LockBoxLib|MdeModulePkg/Library/LockBoxNullLib/LockBoxNullLib.inf
> )
> 
> As to why this breakage was not exposed right at commit 4a1f6b85c184 --
> I have no idea. Perhaps it was hidden by a BaseTools issue that has been
> fixed meanwhile.

Yes.
But it is also a fundamental change in tool behaviour introduced on 9
August. I am really uncomfortable about this making it into the
release this week - but I also believe this is the foundation for the
multiprocess autogen.

Since you have very helpfully analyzed *what* changed ... would the
better "fix" for 2019.08 be to intentionally break the new code to
conform to the old behaviour - and then revert that patch after the
tag?

If we do that, this patch could then wait and indeed be merged as part
of the same set.

> On 08/27/19 14:43, Leif Lindholm wrote:
> > I think a fix for this issue needs to go into 2019.08,
> 
> I agree the problem should be fixed in 2019.08 -- taking your word that
> commit 4a1f6b85c184 *appeared* to fix the MdeModulePkg.dsc build for
> ARM/AARCH64, we now have a regression since that commit (dated
> 2019-03-27).
> 
> > but if someone has a prettier suggestion, I am not wedded to this one.
> 
> I think this is good enough. The lib class resolutions are raised to
> level #2, but they will no longer match ARM / AARCH64, so your level#5
> addition from commit 4a1f6b85c184 will take effect.
> 
> >
> >  MdeModulePkg/MdeModulePkg.dsc | 16 +++++++++++++---
> >  1 file changed, 13 insertions(+), 3 deletions(-)
> >
> > diff --git a/MdeModulePkg/MdeModulePkg.dsc b/MdeModulePkg/MdeModulePkg.dsc
> > index 4320839abfb5..15ba96cecbed 100644
> > --- a/MdeModulePkg/MdeModulePkg.dsc
> > +++ b/MdeModulePkg/MdeModulePkg.dsc
> > @@ -109,6 +109,8 @@ [LibraryClasses.common.PEIM]
> >    HobLib|MdePkg/Library/PeiHobLib/PeiHobLib.inf
> >    MemoryAllocationLib|MdePkg/Library/PeiMemoryAllocationLib/PeiMemoryAllocationLib.inf
> >    ExtractGuidedSectionLib|MdePkg/Library/PeiExtractGuidedSectionLib/PeiExtractGuidedSectionLib.inf
> > +
> > +[LibraryClasses.IA32.PEIM,LibraryClasses.X64.PEIM]
> >    LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxPeiLib.inf
> 
> (1) I suggest replacing "," with ", ". (That's more consistent with
> preexistent section headers in the DSC file.) Applies to the other new
> section headers too.

Yes, fair point.

> >
> >  [LibraryClasses.common.DXE_CORE]
> > @@ -118,18 +120,22 @@ [LibraryClasses.common.DXE_CORE]
> >
> >  [LibraryClasses.common.DXE_DRIVER]
> >    HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
> > -  LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxDxeLib.inf
> >    MemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.inf
> >    ExtractGuidedSectionLib|MdePkg/Library/DxeExtractGuidedSectionLib/DxeExtractGuidedSectionLib.inf
> >    CapsuleLib|MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.inf
> >
> > +[LibraryClasses.IA32.DXE_DRIVER,LibraryClasses.X64.DXE_DRIVER]
> > +  LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxDxeLib.inf
> > +
> >  [LibraryClasses.common.DXE_RUNTIME_DRIVER]
> >    HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
> >    MemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.inf
> >    DebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.inf
> > -  LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxDxeLib.inf
> >    CapsuleLib|MdeModulePkg/Library/DxeCapsuleLibFmp/DxeRuntimeCapsuleLib.inf
> >
> > +[LibraryClasses.IA32.DXE_RUNTIME_DRIVER,LibraryClasses.X64.DXE_RUNTIME_DRIVER]
> > +  LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxDxeLib.inf
> > +
> >  [LibraryClasses.common.SMM_CORE]
> >    HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
> >    MemoryAllocationLib|MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/PiSmmCoreMemoryAllocationLib.inf
> > @@ -143,13 +149,17 @@ [LibraryClasses.common.DXE_SMM_DRIVER]
> >    MemoryAllocationLib|MdePkg/Library/SmmMemoryAllocationLib/SmmMemoryAllocationLib.inf
> >    MmServicesTableLib|MdePkg/Library/MmServicesTableLib/MmServicesTableLib.inf
> >    SmmServicesTableLib|MdePkg/Library/SmmServicesTableLib/SmmServicesTableLib.inf
> > +  SmmMemLib|MdePkg/Library/SmmMemLib/SmmMemLib.inf
> > +
> > +[LibraryClasses.IA32.DXE_SMM_DRIVER,LibraryClasses.X64.DXE_SMM_DRIVER]
> >    LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxSmmLib.inf
> > -  SmmMemLib|MdePkg/Library/SmmMemLib/SmmMemLib.inf
> >
> 
> I wonder if this is really necessary. I would assume all the
> DXE_SMM_DRIVER modules are listed under
> 
>   [Components.IA32, Components.X64]
> 
> already. But, this hunk certainly doesn't hurt.

Well, this fixes the current issue. I completely agree the file could
benefit from some overall restructuring.

> >  [LibraryClasses.common.UEFI_DRIVER]
> >    HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
> >    MemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.inf
> >    DebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.inf
> > +
> > +[LibraryClasses.IA32.UEFI_DRIVER,LibraryClasses.X64.UEFI_DRIVER]
> >    LockBoxLib|MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxDxeLib.inf
> >
> >  [LibraryClasses.common.UEFI_APPLICATION]
> >
> 
> With (1) fixed (feel free to correct that just before pushing):
> 
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Thanks!

> Do wait for maintainer review, of course.

Of course.

Best Regards,

Leif