[kvm-unit-tests PATCH v3 0/6] arm64: improve debuggability

Nadav Amit
2023-06-28T00:14:36Z

My recent experience in debugging ARM64 tests on EFI was not as fun as I
expected it to be.

There were several reasons for that besides the questionable definition
of "fun":

1. ARM64 is not compiled with frame pointers and there is no stack
unwinder when the stack is dumped.

2. Building an EFI drops the debug information.

3. The addresses that are printed on dump_stack() and the use of GDB
are hard because taking code relocation into account is non trivial.

The patches help both ARM64 and EFI for this matter. The image address
is printed when EFI is used to allow the use of GDB. Symbols are emitted
into a separate debug file. The frame pointer is included and special
entry is added upon an exception to allow backtracing across
exceptions.

[ PowerPC: Please ack patches 1,2 ]
[ x86: Please ack patches 1,2,5 ]

v2->v3:
* Consider PowerPC for reloc and related fixes [Andrew]

v1->v2:
* Andrew comments [see in individual patches]
* Few cleanups

Nadav Amit (6):
efi: keep efi debug information in a separate file
lib/stack: print base addresses on relocation setups
arm64: enable frame pointer and support stack unwinding
arm64: stack: update trace stack on exception
efi: print address of image
arm64: dump stack on bad exception

.gitignore | 1 +
Makefile | 2 +-
arm/Makefile.arm | 3 --
arm/Makefile.arm64 | 2 ++
arm/Makefile.common | 8 +++++-
arm/cstart64.S | 13 +++++++++
lib/arm64/asm-offsets.c | 6 +++-
lib/arm64/asm/stack.h | 3 ++
lib/arm64/processor.c | 1 +
lib/arm64/stack.c | 62 +++++++++++++++++++++++++++++++++++++++++
lib/efi.c | 4 +++
lib/stack.c | 31 +++++++++++++++++++--
powerpc/Makefile.common | 1 +
x86/Makefile.common | 5 +++-
14 files changed, 133 insertions(+), 9 deletions(-)
create mode 100644 lib/arm64/stack.c

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2.34.1