diff mbox

[edk2,2/2] ArmVirtPkg ARM: make relocatable PrePi users build with CLANG35

Message ID 1470212464-28071-3-git-send-email-ard.biesheuvel@linaro.org
State Accepted
Commit 87ee6390cbeb2d15490943bca2978f166f213c13
Headers show

Commit Message

Ard Biesheuvel Aug. 3, 2016, 8:21 a.m. UTC 
The clang developers have made a backward incompatible change to the
command line arguments, and have replaced '-mllvm -arm-use-movt=0'
with '-mno-movt'. This does not matter for most ARM platforms, and
therefore it has been removed from the default CLANG35/ARM CC flags
in patch 1c63516075b3 ("BaseTools CLANG35: drop problematic use-movt
and save-temps options"), but as it turns out, the relocatable PrePi
implementation used by ArmVirtQemuKernel and ArmVirtXen will fail to
build if it contains MOVT/MOVW pairs, due to the fact that these are
not runtime relocatable under ELF.

Since they are runtime relocatable under PE/COFF, and GenFw does the
right thing when encountering them, selectively controlling their
use is more appropriate than disabling them altogether. Therefore,
this patch adds the -mno-movt argument only for the platforms that
use the relocatable PrePi, and only for the module types that may
be pulled into its build.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

---
 ArmVirtPkg/ArmVirtQemuKernel.dsc | 8 ++++++++
 ArmVirtPkg/ArmVirtXen.dsc        | 9 +++++++++
 2 files changed, 17 insertions(+)

-- 
2.7.4

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Comments

Laszlo Ersek Aug. 3, 2016, 10 a.m. UTC | #1 
On 08/03/16 10:21, Ard Biesheuvel wrote:
> The clang developers have made a backward incompatible change to the

> command line arguments, and have replaced '-mllvm -arm-use-movt=0'

> with '-mno-movt'. This does not matter for most ARM platforms, and

> therefore it has been removed from the default CLANG35/ARM CC flags

> in patch 1c63516075b3 ("BaseTools CLANG35: drop problematic use-movt

> and save-temps options"), but as it turns out, the relocatable PrePi

> implementation used by ArmVirtQemuKernel and ArmVirtXen will fail to

> build if it contains MOVT/MOVW pairs, due to the fact that these are

> not runtime relocatable under ELF.

> 

> Since they are runtime relocatable under PE/COFF, and GenFw does the

> right thing when encountering them, selectively controlling their

> use is more appropriate than disabling them altogether. Therefore,

> this patch adds the -mno-movt argument only for the platforms that

> use the relocatable PrePi, and only for the module types that may

> be pulled into its build.

> 

> Contributed-under: TianoCore Contribution Agreement 1.0

> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> ---

>  ArmVirtPkg/ArmVirtQemuKernel.dsc | 8 ++++++++

>  ArmVirtPkg/ArmVirtXen.dsc        | 9 +++++++++

>  2 files changed, 17 insertions(+)

> 

> diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc

> index 01a1d9b4613b..6c536d9bbd2d 100644

> --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc

> +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc

> @@ -45,6 +45,9 @@ [LibraryClasses.ARM]

>    ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf

>    ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf

>  

> +[LibraryClasses.ARM.SEC]

> +  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf

> +


How does this library resolution change relate to the stated purpose of
the patch?

Thanks
Laszlo

>  [LibraryClasses.common]

>    ArmMmuLib|ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf

>  

> @@ -77,6 +80,11 @@ [BuildOptions]

>    GCC:*_*_ARM_PLATFORM_FLAGS == -mcpu=cortex-a15 -I$(WORKSPACE)/ArmVirtPkg/Include

>    *_*_AARCH64_PLATFORM_FLAGS == -I$(WORKSPACE)/ArmVirtPkg/Include

>  

> +[BuildOptions.ARM.EDKII.SEC, BuildOptions.ARM.EDKII.BASE]

> +  # Avoid MOVT/MOVW instruction pairs in code that may end up in the PIE

> +  # executable we build for the relocatable PrePi. They are not runtime

> +  # relocatable in ELF.

> +  *_CLANG35_*_CC_FLAGS = -mno-movt

>  

>  ################################################################################

>  #

> diff --git a/ArmVirtPkg/ArmVirtXen.dsc b/ArmVirtPkg/ArmVirtXen.dsc

> index 5ad1bf630bda..4ebead5ba6e6 100644

> --- a/ArmVirtPkg/ArmVirtXen.dsc

> +++ b/ArmVirtPkg/ArmVirtXen.dsc

> @@ -44,6 +44,9 @@ [LibraryClasses.ARM]

>    ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf

>    ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf

>  

> +[LibraryClasses.ARM.SEC]

> +  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf

> +

>  [LibraryClasses.common]

>    ArmMmuLib|ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf

>  

> @@ -77,6 +80,12 @@ [BuildOptions]

>    GCC:*_*_ARM_PLATFORM_FLAGS == -mcpu=cortex-a15 -I$(WORKSPACE)/ArmVirtPkg/Include

>    GCC:*_*_AARCH64_PLATFORM_FLAGS == -I$(WORKSPACE)/ArmVirtPkg/Include

>  

> +[BuildOptions.ARM.EDKII.SEC, BuildOptions.ARM.EDKII.BASE]

> +  # Avoid MOVT/MOVW instruction pairs in code that may end up in the PIE

> +  # executable we build for the relocatable PrePi. They are not runtime

> +  # relocatable in ELF.

> +  *_CLANG35_*_CC_FLAGS = -mno-movt

> +

>  ################################################################################

>  #

>  # Pcd Section - list of all EDK II PCD Entries defined by this Platform

> 


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Ard Biesheuvel Aug. 3, 2016, 10:02 a.m. UTC | #2 
On 3 August 2016 at 12:00, Laszlo Ersek <lersek@redhat.com> wrote:
> On 08/03/16 10:21, Ard Biesheuvel wrote:

>> The clang developers have made a backward incompatible change to the

>> command line arguments, and have replaced '-mllvm -arm-use-movt=0'

>> with '-mno-movt'. This does not matter for most ARM platforms, and

>> therefore it has been removed from the default CLANG35/ARM CC flags

>> in patch 1c63516075b3 ("BaseTools CLANG35: drop problematic use-movt

>> and save-temps options"), but as it turns out, the relocatable PrePi

>> implementation used by ArmVirtQemuKernel and ArmVirtXen will fail to

>> build if it contains MOVT/MOVW pairs, due to the fact that these are

>> not runtime relocatable under ELF.

>>

>> Since they are runtime relocatable under PE/COFF, and GenFw does the

>> right thing when encountering them, selectively controlling their

>> use is more appropriate than disabling them altogether. Therefore,

>> this patch adds the -mno-movt argument only for the platforms that

>> use the relocatable PrePi, and only for the module types that may

>> be pulled into its build.

>>

>> Contributed-under: TianoCore Contribution Agreement 1.0

>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

>> ---

>>  ArmVirtPkg/ArmVirtQemuKernel.dsc | 8 ++++++++

>>  ArmVirtPkg/ArmVirtXen.dsc        | 9 +++++++++

>>  2 files changed, 17 insertions(+)

>>

>> diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>> index 01a1d9b4613b..6c536d9bbd2d 100644

>> --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc

>> +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>> @@ -45,6 +45,9 @@ [LibraryClasses.ARM]

>>    ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf

>>    ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf

>>

>> +[LibraryClasses.ARM.SEC]

>> +  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf

>> +

>

> How does this library resolution change relate to the stated purpose of

> the patch?

>


It prevents a version of ArmLib being pulled into the build of the
relocatable PrePi that was built using the BuildOptions for DXE_DRIVER
type modules.

-- 
Ard.
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Laszlo Ersek Aug. 3, 2016, 11:19 a.m. UTC | #3 
On 08/03/16 12:02, Ard Biesheuvel wrote:
> On 3 August 2016 at 12:00, Laszlo Ersek <lersek@redhat.com> wrote:

>> On 08/03/16 10:21, Ard Biesheuvel wrote:

>>> The clang developers have made a backward incompatible change to the

>>> command line arguments, and have replaced '-mllvm -arm-use-movt=0'

>>> with '-mno-movt'. This does not matter for most ARM platforms, and

>>> therefore it has been removed from the default CLANG35/ARM CC flags

>>> in patch 1c63516075b3 ("BaseTools CLANG35: drop problematic use-movt

>>> and save-temps options"), but as it turns out, the relocatable PrePi

>>> implementation used by ArmVirtQemuKernel and ArmVirtXen will fail to

>>> build if it contains MOVT/MOVW pairs, due to the fact that these are

>>> not runtime relocatable under ELF.

>>>

>>> Since they are runtime relocatable under PE/COFF, and GenFw does the

>>> right thing when encountering them, selectively controlling their

>>> use is more appropriate than disabling them altogether. Therefore,

>>> this patch adds the -mno-movt argument only for the platforms that

>>> use the relocatable PrePi, and only for the module types that may

>>> be pulled into its build.

>>>

>>> Contributed-under: TianoCore Contribution Agreement 1.0

>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

>>> ---

>>>  ArmVirtPkg/ArmVirtQemuKernel.dsc | 8 ++++++++

>>>  ArmVirtPkg/ArmVirtXen.dsc        | 9 +++++++++

>>>  2 files changed, 17 insertions(+)

>>>

>>> diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>> index 01a1d9b4613b..6c536d9bbd2d 100644

>>> --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>> +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>> @@ -45,6 +45,9 @@ [LibraryClasses.ARM]

>>>    ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf

>>>    ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf

>>>

>>> +[LibraryClasses.ARM.SEC]

>>> +  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf

>>> +

>>

>> How does this library resolution change relate to the stated purpose of

>> the patch?

>>

> 

> It prevents a version of ArmLib being pulled into the build of the

> relocatable PrePi that was built using the BuildOptions for DXE_DRIVER

> type modules.

> 


I think it would be reasonable to add this one paragraph to the commit
message as well. If you disagree, I won't insist. :)

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

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Ard Biesheuvel Aug. 3, 2016, 12:51 p.m. UTC | #4 
On 3 August 2016 at 13:19, Laszlo Ersek <lersek@redhat.com> wrote:
> On 08/03/16 12:02, Ard Biesheuvel wrote:

>> On 3 August 2016 at 12:00, Laszlo Ersek <lersek@redhat.com> wrote:

>>> On 08/03/16 10:21, Ard Biesheuvel wrote:

>>>> The clang developers have made a backward incompatible change to the

>>>> command line arguments, and have replaced '-mllvm -arm-use-movt=0'

>>>> with '-mno-movt'. This does not matter for most ARM platforms, and

>>>> therefore it has been removed from the default CLANG35/ARM CC flags

>>>> in patch 1c63516075b3 ("BaseTools CLANG35: drop problematic use-movt

>>>> and save-temps options"), but as it turns out, the relocatable PrePi

>>>> implementation used by ArmVirtQemuKernel and ArmVirtXen will fail to

>>>> build if it contains MOVT/MOVW pairs, due to the fact that these are

>>>> not runtime relocatable under ELF.

>>>>

>>>> Since they are runtime relocatable under PE/COFF, and GenFw does the

>>>> right thing when encountering them, selectively controlling their

>>>> use is more appropriate than disabling them altogether. Therefore,

>>>> this patch adds the -mno-movt argument only for the platforms that

>>>> use the relocatable PrePi, and only for the module types that may

>>>> be pulled into its build.

>>>>

>>>> Contributed-under: TianoCore Contribution Agreement 1.0

>>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

>>>> ---

>>>>  ArmVirtPkg/ArmVirtQemuKernel.dsc | 8 ++++++++

>>>>  ArmVirtPkg/ArmVirtXen.dsc        | 9 +++++++++

>>>>  2 files changed, 17 insertions(+)

>>>>

>>>> diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>>> index 01a1d9b4613b..6c536d9bbd2d 100644

>>>> --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>>> +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc

>>>> @@ -45,6 +45,9 @@ [LibraryClasses.ARM]

>>>>    ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf

>>>>    ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf

>>>>

>>>> +[LibraryClasses.ARM.SEC]

>>>> +  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf

>>>> +

>>>

>>> How does this library resolution change relate to the stated purpose of

>>> the patch?

>>>

>>

>> It prevents a version of ArmLib being pulled into the build of the

>> relocatable PrePi that was built using the BuildOptions for DXE_DRIVER

>> type modules.

>>

>

> I think it would be reasonable to add this one paragraph to the commit

> message as well. If you disagree, I won't insist. :)

>


No, you're quite right. I'm still a bit confused that a SEC module can
include DXE_DRIVER type libraries, but I guess it doesn't matter if
there is no constructor.

> Reviewed-by: Laszlo Ersek <lersek@redhat.com>


Thank you,
Ard.
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diff mbox

Patch

diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc
index 01a1d9b4613b..6c536d9bbd2d 100644
--- a/ArmVirtPkg/ArmVirtQemuKernel.dsc
+++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc
@@ -45,6 +45,9 @@  [LibraryClasses.ARM]
   ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf
   ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf
 
+[LibraryClasses.ARM.SEC]
+  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf
+
 [LibraryClasses.common]
   ArmMmuLib|ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf
 
@@ -77,6 +80,11 @@  [BuildOptions]
   GCC:*_*_ARM_PLATFORM_FLAGS == -mcpu=cortex-a15 -I$(WORKSPACE)/ArmVirtPkg/Include
   *_*_AARCH64_PLATFORM_FLAGS == -I$(WORKSPACE)/ArmVirtPkg/Include
 
+[BuildOptions.ARM.EDKII.SEC, BuildOptions.ARM.EDKII.BASE]
+  # Avoid MOVT/MOVW instruction pairs in code that may end up in the PIE
+  # executable we build for the relocatable PrePi. They are not runtime
+  # relocatable in ELF.
+  *_CLANG35_*_CC_FLAGS = -mno-movt
 
 ################################################################################
 #
diff --git a/ArmVirtPkg/ArmVirtXen.dsc b/ArmVirtPkg/ArmVirtXen.dsc
index 5ad1bf630bda..4ebead5ba6e6 100644
--- a/ArmVirtPkg/ArmVirtXen.dsc
+++ b/ArmVirtPkg/ArmVirtXen.dsc
@@ -44,6 +44,9 @@  [LibraryClasses.ARM]
   ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7Lib.inf
   ArmCpuLib|ArmPkg/Drivers/ArmCpuLib/ArmCortexA15Lib/ArmCortexA15Lib.inf
 
+[LibraryClasses.ARM.SEC]
+  ArmLib|ArmPkg/Library/ArmLib/ArmV7/ArmV7LibSec.inf
+
 [LibraryClasses.common]
   ArmMmuLib|ArmPkg/Library/ArmMmuLib/ArmMmuBaseLib.inf
 
@@ -77,6 +80,12 @@  [BuildOptions]
   GCC:*_*_ARM_PLATFORM_FLAGS == -mcpu=cortex-a15 -I$(WORKSPACE)/ArmVirtPkg/Include
   GCC:*_*_AARCH64_PLATFORM_FLAGS == -I$(WORKSPACE)/ArmVirtPkg/Include
 
+[BuildOptions.ARM.EDKII.SEC, BuildOptions.ARM.EDKII.BASE]
+  # Avoid MOVT/MOVW instruction pairs in code that may end up in the PIE
+  # executable we build for the relocatable PrePi. They are not runtime
+  # relocatable in ELF.
+  *_CLANG35_*_CC_FLAGS = -mno-movt
+
 ################################################################################
 #
 # Pcd Section - list of all EDK II PCD Entries defined by this Platform