A large part of the content of the bug.h is repeated among all
architectures (especially x86 and RISCV have the same implementation), so it
was created a new config CONFIG_GENERIC_BUG_FRAME which is used to
introduce generic implementation of do_bug_frame() and move x86's <asm/bug.h>
to <xen/common/...> with the following changes:
  * Add inclusion of arch-specific header <asm/bug.h>
  * Rename the guard and remove x86 specific changes
  * Wrap macros BUG_FRAME/run_in_exception_handler/WARN/BUG/assert_failed/etc
    into #ifndef "BUG_FRAME/run_in_exception_handler/WARN/BUG/assert_failed/etc"
    thereby each architecture can override the generic implementation of macros.
  * Add #if{n}def __ASSEMBLY__ ... #endif
  * Introduce BUG_FRAME_STRUCTURE define to be able to change the structure of bug
    frame
  * Introduce BUG_INSTR and MODIFIER to make _ASM_BUGFRAME_TEXT reusable between x86 and
    RISC-V.
  * Make macros related to bug frame structure more generic.

For ARM only common parts were removed from <asm/bug.h> and re-use generic
do_bug_frame() for ARM.

RISC-V will be switched to use <xen/bug.h> and in the future, it will use common
the version of do_bug_frame() when xen/common will work for RISC-V.

---
Changes in V2:
  * Update cover letter.
  * Switch to x86 implementation as generic as it is more compact ( at least from the point of view of bug frame structure).
  * Put [PATCH v1 4/4] xen: change <asm/bug.h> to <xen/bug.h> as second patch,
    update the patch to change all <asm/bug.h> to <xen/bug.h> among the whole project
    to not break compilation.
  * Rename CONFIG_GENERIC_DO_BUG_FRAME to CONFIG_GENERIC_BUG_FRAME.
  * Change the macro bug_loc(b) to avoid the need for a cast:
    #define bug_loc(b) ((unsigned long)(b) + (b)->loc_disp)
  * Rename BUG_FRAME_STUFF to BUG_FRAME_STRUCT
  * Make macros related to bug frame structure more generic.
  * Rename bug_file() in ARM implementation to bug_ptr() as generic do_bug_frame() uses
    bug_ptr().
  * Introduce BUG_INSTR and MODIFIER to make _ASM_BUGFRAME_TEXT reusable between x86 and
    RISC-V.
  * Rework do_invalid_op() in x86 ( re-use handle_bug_frame() and find_bug_frame() )
---
Oleksii Kurochko (4):
  xen: introduce CONFIG_GENERIC_BUG_FRAME
  xen: change <asm/bug.h> to <xen/bug.h>
  xen/arm: switch ARM to use generic implementation of bug.h
  xen/x86: switch x86 to use generic implemetation of bug.h

 xen/arch/arm/Kconfig                 |   1 +
 xen/arch/arm/include/asm/bug.h       |  32 +-----
 xen/arch/arm/include/asm/div64.h     |   2 +-
 xen/arch/arm/include/asm/traps.h     |   2 -
 xen/arch/arm/traps.c                 |  79 -------------
 xen/arch/arm/vgic/vgic-v2.c          |   2 +-
 xen/arch/arm/vgic/vgic.c             |   2 +-
 xen/arch/x86/Kconfig                 |   1 +
 xen/arch/x86/acpi/cpufreq/cpufreq.c  |   2 +-
 xen/arch/x86/include/asm/asm_defns.h |   2 +-
 xen/arch/x86/include/asm/bug.h       |  88 +--------------
 xen/arch/x86/traps.c                 |  81 +++-----------
 xen/common/Kconfig                   |   3 +
 xen/common/Makefile                  |   1 +
 xen/common/bug.c                     | 113 +++++++++++++++++++
 xen/drivers/cpufreq/cpufreq.c        |   2 +-
 xen/include/xen/bug.h                | 161 +++++++++++++++++++++++++++
 xen/include/xen/lib.h                |   2 +-
 18 files changed, 306 insertions(+), 270 deletions(-)
 create mode 100644 xen/common/bug.c
 create mode 100644 xen/include/xen/bug.h

-- 
2.39.0