Re: [PATCH v2 5/5] ArmPkg/DefaultExceptionHandlerLib: use console if available

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On Tue, 15 Jan 2019 at 11:09, Laszlo Ersek <lersek@redhat.com> wrote:
>
> On 01/15/19 09:23, Ard Biesheuvel wrote:
> > Print the minimal 'exception occurred' message to the console instead
> > of straight to the serial port if the console is available. This makes
> > such messages visible on systems where the console is graphical and
> > the serial is not connected.
> >
> > Contributed-under: TianoCore Contribution Agreement 1.1
> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
> > ---
> >  ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c | 12 ++++++++++--
> >  ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c     |  7 ++++++-
> >  ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf    |  1 +
> >  3 files changed, 17 insertions(+), 3 deletions(-)
>
> Please consider updating the following, before pushing the patch:
>
> > diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
> > index 1024bf48c63d..362acd5ba6d2 100644
> > --- a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
> > +++ b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
> > @@ -22,6 +22,7 @@
> >  #include <Library/PrintLib.h>
> >  #include <Library/ArmDisassemblerLib.h>
> >  #include <Library/SerialPortLib.h>
> > +#include <Library/UefiBootServicesTableLib.h>
> >
> >  #include <Guid/DebugImageInfoTable.h>
> >  #include <Protocol/DebugSupport.h>
> > @@ -159,14 +160,21 @@ DefaultExceptionHandler (
> >    INT32  Offset;
> >
> >    if (mRecursiveException) {
> > -    CharCount = AsciiSPrint (Buffer, sizeof (Buffer),"\nRecursive exception occurred while dumping the CPU state\n");
> > -    SerialPortWrite ((UINT8 *) Buffer, CharCount);
> > +    STATIC CHAR8 CONST Message[] = "\nRecursive exception occurred while dumping the CPU state\n";
> > +
> > +    SerialPortWrite ((UINT8 *)Message, AsciiStrLen (Message));
>
> (1) A micro-optimization could be (sizeof Message - 1) rather than
> AsciiStrLen (Message), but it's mostly irrelevant.
>

OK

> > +    if (gST->ConOut != NULL) {
> > +      AsciiPrint (Message);
> > +    }
> >      CpuDeadLoop ();
> >    }
> >    mRecursiveException = TRUE;
> >
> >    CharCount = AsciiSPrint (Buffer,sizeof (Buffer),"\n\n%a Exception at 0x%016lx\n", gExceptionTypeString[ExceptionType], SystemContext.SystemContextAArch64->ELR);
> >    SerialPortWrite ((UINT8 *) Buffer, CharCount);
> > +  if (gST->ConOut != NULL) {
> > +    AsciiPrint (Buffer);
> > +  }
> >
> >    DEBUG_CODE_BEGIN ();
> >      CHAR8  *Pdb, *PrevPdb;
> > diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
> > index cc79cb2fa301..a79f73725aed 100644
> > --- a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
> > +++ b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
> > @@ -21,6 +21,7 @@
> >  #include <Library/PrintLib.h>
> >  #include <Library/ArmDisassemblerLib.h>
> >  #include <Library/SerialPortLib.h>
> > +#include <Library/UefiBootServicesTableLib.h>
> >
> >  #include <Guid/DebugImageInfoTable.h>
> >
> > @@ -194,7 +195,11 @@ DefaultExceptionHandler (
> >
> >    CharCount = AsciiSPrint (Buffer,sizeof (Buffer),"\n%a Exception PC at 0x%08x  CPSR 0x%08x ",
> >           gExceptionTypeString[ExceptionType], SystemContext.SystemContextArm->PC, SystemContext.SystemContextArm->CPSR);
> > -  SerialPortWrite ((UINT8 *) Buffer, CharCount);
> > +  if (gST->ConOut != NULL) {
> > +    AsciiPrint (Buffer);
> > +  } else {
> > +    SerialPortWrite ((UINT8 *)Buffer, CharCount);
> > +  }
>
> (2) I think the "serial PLUS console" reporting applies to the 32-bit
> lib instance as well, so I assume not updating this from v1 was an
> oversight.
>

Yes it was. Thanks for spotting that.

> >
> >    DEBUG_CODE_BEGIN ();
> >      CHAR8   *Pdb;
> > diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf b/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
> > index 7609f82d89a1..6bc48714c9dc 100644
> > --- a/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
> > +++ b/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
> > @@ -42,6 +42,7 @@ [LibraryClasses]
> >    PeCoffGetEntryPointLib
> >    ArmDisassemblerLib
> >    SerialPortLib
> > +  UefiBootServicesTableLib
> >
> >  [Guids]
> >    gEfiDebugImageInfoTableGuid
> >
>
> With (2) updated, and regardless of (1):
>
> Acked-by: Laszlo Ersek <lersek@redhat.com>
>
> Thanks!
> Laszlo