[v3,0/6] Remove unconditional arch dependency on asm/debugger.h

Message

Bobby Eshleman Aug. 18, 2021, 8:29 p.m. UTC

This series removes the unconditional requirement that all architectures
implement asm/debugger.h. It additionally removes arm's debugger.h and
disentangles some of the x86 gdbsx/gdbstub/generic debugger code.

Additionally, this series does the following:
- Provides generic stubs when !CONFIG_CRASH_DEBUG
- Adds stronger separation between gdbstub, gdbsx, and generic debugger
  code.

The patches in this v3 are quite a bit different than in v2, so
per-patch changes are omitted. This difference in the patchset version
is largely due to the need to decouple the debugger_trap_* functions.

Changes from v2:
- The first patch drops ARM's calls to the debugger stubs, removing the
  need to add fake values.
- No debugger.c is added, as it was unnecessary when code was moved into
  existing and appropriate files.
- debugger_trap_entry() expands inline into its few call sites
- debug.c becomes gdbsx.c
- All gdbsx functions move into gdbsx.c and become dependent on
  CONFIG_GDBSX (instead of CONFIG_CRASH_DEBUG as was the case for
  domain_pause_for_debugger(), for example)

It's worth noting that debugger.h is still not truly generic as
debugger_trap_fatal() for x86 necessarily calls into the gdbstub… but
further generalization is unnecessary while it is still only
backed by the gdbstub.

As I'm not *exactly* an expert on this code, so feel free to inform me of my
confusion where you see it.

Bobby Eshleman (6):
  arm/traps: remove debugger_trap_fatal() calls
  x86/debugger: separate Xen and guest debugging debugger_trap_*
    functions
  arch/x86: rename debug.c to gdbsx.c
  x86/gdbsx: expand dbg_rw_mem() inline
  arch/x86: move domain_pause_for_debugger() to domain.h
  x86: change asm/debugger.h to xen/debugger.h

 xen/arch/arm/traps.c              |  7 ----
 xen/arch/x86/Makefile             |  2 +-
 xen/arch/x86/domain.c             |  2 +-
 xen/arch/x86/domctl.c             | 12 +-----
 xen/arch/x86/{debug.c => gdbsx.c} | 30 +++++++-------
 xen/arch/x86/hvm/svm/svm.c        |  2 +-
 xen/arch/x86/hvm/vmx/realmode.c   |  2 +-
 xen/arch/x86/hvm/vmx/vmx.c        |  2 +-
 xen/arch/x86/nmi.c                |  1 -
 xen/arch/x86/traps.c              | 51 ++++++++++++++----------
 xen/common/domain.c               |  2 +-
 xen/common/gdbstub.c              |  2 +-
 xen/common/keyhandler.c           |  2 +-
 xen/common/shutdown.c             |  2 +-
 xen/drivers/char/console.c        |  2 +-
 xen/include/asm-arm/debugger.h    | 15 -------
 xen/include/asm-x86/debugger.h    | 65 +------------------------------
 xen/include/asm-x86/domain.h      |  2 +
 xen/include/asm-x86/gdbsx.h       | 17 ++++++++
 xen/include/xen/debugger.h        | 51 ++++++++++++++++++++++++
 20 files changed, 127 insertions(+), 144 deletions(-)
 rename xen/arch/x86/{debug.c => gdbsx.c} (89%)
 delete mode 100644 xen/include/asm-arm/debugger.h
 create mode 100644 xen/include/asm-x86/gdbsx.h
 create mode 100644 xen/include/xen/debugger.h