Re: [PATCH v3 00/18] monitor/hmp: replace MonitorDef with GDB registers

["Dr. David Alan Gilbert" <dave@treblig.org>]

* Marc-André Lureau (marcandre.lureau@redhat.com) wrote:
> Hi
> 
> On Sat, Oct 24, 2026 at 7:52 PM Dr. David Alan Gilbert <dave@treblig.org> wrote:
> >
> > * Marc-André Lureau (marcandre.lureau@redhat.com) wrote:
> > > Hi,
> > >
> > > HMP monitor supports printing $register expression. The lookup
> > > was done via GDB stub registers, and supplementary MonitorDef
> > > HMP-specific tables.
> >
> > Why don't you get the first ~3 of these merged and then you can take the
> > others through the individual targets at their own pace.
> 
> Because I am not a GDB stub or HMP maintainer. Should I send a PR
> regardless for those? they can be reviewed & applied at a maintainer
> pace.

The first one looks trivial to me.

> If you think it's too slow, I can agree :)

It's not the 'slow', it just would avoid needing to keep big patchsets
running around and everyone having to check them again each time.

Dave

> >
> > Dave
> >
> > > Migrate HMP registers to use the GDB infrastructure and remove the
> > > legacy HMP MonitorDef. Internal registers aren't exposed to GDB.
> > > This also drops HMP $pc x86 fallback (use $eip/$rip instead).
> > >
> > > Known behavioural changes on RISC-V: CSR lookup is now case-sensitive
> > > and vector registers now report "unkown register" instead of a
> > > target-specific message ("Unable to print the value of vector vreg 'v0'
> > > from this API")
> > >
> > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > > ---
> > > Changes in v3:
> > > - added x86 GDB register patches
> > >   - fix the x87 FPU tag word returned by the GDB stub
> > >   - split SSE registers into a separate org.gnu.gdb.i386.sse feature
> > >   - expose AVX/AVX-512 registers (ymm/zmm upper halves and opmask)
> > >   - expose more system registers to HMP
> > > - renamed i386-segments.xml to i386-system.xml and registered it as an
> > >   internal feature, like the other targets
> > > - moved the HMP $pc removal to its own patch and documented it in
> > >   removed-features.rst
> > > - moved each target's MonitorDef removal into its target patch; the final
> > >   patch now only removes the generic MonitorDef infrastructure
> > > - added MAINTAINERS entries
> > > - rebased onto current master
> > > - Link to v2: https://lore.kernel.org/qemu-devel/20261013-query-reg-v2-0-6f95a2e139a9@redhat.com
> > >
> > > Changes in v2:
> > > - dropped v1 patch 5 (CPUClass::get_pc fallback for $pc)
> > > - new patch gdb_register_internal_coprocessor() to hide registers from GDB
> > > - SPARC64, m68k, RISC-V aliases now use internal registration
> > > - pickup trailer tags
> > > - Link to v1: https://lore.kernel.org/qemu-devel/20260911-query-reg-v1-0-0c04f0c02cf3@redhat.com
> > >
> > > ---
> > > Marc-André Lureau (18):
> > >       hmp: don't crash on invalid register
> > >       gdbstub: fix next register base after register gaps
> > >       gdbstub: set feature->base_reg for dynamic features
> > >       gdbstub: add gdb_register_internal_coprocessor()
> > >       MAINTAINERS: cover x86 GDB XML files
> > >       target/i386: expose segment limits register to monitors via gdbstub
> > >       target/i386: fix FPU tag word in GDB register read
> > >       target/i386: split SSE registers into separate GDB feature
> > >       target/i386: expose system registers to monitors via gdbstub
> > >       target/i386: expose AVX/AVX-512 registers to GDB
> > >       target/i386: drop HMP $pc
> > >       MAINTAINERS: cover m68k GDB XML files
> > >       target/m68k: expose system registers to monitors via gdbstub
> > >       target/sparc64: expose system registers to monitors via gdbstub
> > >       target/riscv: bypass smstateen check in debugger mode
> > >       MAINTAINERS: cover riscv GDB XML files
> > >       target/riscv: expose register aliases to monitors via gdbstub
> > >       monitor/hmp: remove legacy MonitorDef infrastructure
> > >
> > >  MAINTAINERS                               |   4 +
> > >  configs/targets/i386-bsd-user.mak         |   2 +-
> > >  configs/targets/i386-linux-user.mak       |   2 +-
> > >  configs/targets/i386-softmmu.mak          |   2 +-
> > >  configs/targets/m68k-softmmu.mak          |   2 +-
> > >  configs/targets/riscv32-linux-user.mak    |   2 +-
> > >  configs/targets/riscv32-softmmu.mak       |   2 +-
> > >  configs/targets/riscv64-bsd-user.mak      |   2 +-
> > >  configs/targets/riscv64-linux-user.mak    |   2 +-
> > >  configs/targets/riscv64-softmmu.mak       |   2 +-
> > >  configs/targets/sparc64-softmmu.mak       |   2 +-
> > >  configs/targets/x86_64-bsd-user.mak       |   2 +-
> > >  configs/targets/x86_64-linux-user.mak     |   2 +-
> > >  configs/targets/x86_64-softmmu.mak        |   2 +-
> > >  docs/about/removed-features.rst           |   8 +
> > >  gdbstub/gdb-xml/i386-32bit-avx.xml        |  20 ++
> > >  gdbstub/gdb-xml/i386-32bit-avx512.xml     |  31 +++
> > >  gdbstub/gdb-xml/i386-32bit-sse.xml        |  54 +++++
> > >  gdbstub/gdb-xml/i386-32bit.xml            |  46 +---
> > >  gdbstub/gdb-xml/i386-64bit-avx.xml        |  28 +++
> > >  gdbstub/gdb-xml/i386-64bit-avx512.xml     | 108 +++++++++
> > >  gdbstub/gdb-xml/i386-64bit-sse.xml        |  62 +++++
> > >  gdbstub/gdb-xml/i386-64bit.xml            |  50 ----
> > >  gdbstub/gdb-xml/i386-system.xml           |  53 +++++
> > >  gdbstub/gdb-xml/m68k-system.xml           |  32 +++
> > >  gdbstub/gdb-xml/riscv-32bit-alias.xml     | 105 +++++++++
> > >  gdbstub/gdb-xml/riscv-32bit-fpu-alias.xml |  40 ++++
> > >  gdbstub/gdb-xml/riscv-64bit-alias.xml     | 105 +++++++++
> > >  gdbstub/gdb-xml/riscv-64bit-fpu-alias.xml |  46 ++++
> > >  gdbstub/gdb-xml/sparc64-system.xml        |  22 ++
> > >  gdbstub/gdbstub.c                         |  85 +++++--
> > >  include/exec/gdbstub.h                    |  21 ++
> > >  include/hw/core/cpu.h                     |   5 +-
> > >  include/hw/core/sysemu-cpu-ops.h          |  16 --
> > >  include/monitor/hmp.h                     |   6 -
> > >  include/qemu/typedefs.h                   |   1 -
> > >  monitor/hmp.c                             |  45 +---
> > >  target/arm/gdbstub.c                      |   8 +-
> > >  target/arm/gdbstub64.c                    |  10 +-
> > >  target/i386/cpu-dump.c                    |   5 +-
> > >  target/i386/cpu.c                         |  60 +++--
> > >  target/i386/cpu.h                         |  25 ++
> > >  target/i386/gdbstub.c                     | 373 +++++++++++++++++++++++++++---
> > >  target/i386/tcg/fpu_helper.c              |  24 +-
> > >  target/m68k/cpu.c                         |  22 --
> > >  target/m68k/helper.c                      |  49 +++-
> > >  target/ppc/gdbstub.c                      |   2 +-
> > >  target/riscv/cpu.c                        |   1 -
> > >  target/riscv/gdbstub.c                    |  57 ++++-
> > >  target/riscv/internals.h                  |   3 -
> > >  target/riscv/monitor.c                    | 140 -----------
> > >  target/riscv/tcg/csr.c                    |   3 +-
> > >  target/sparc/cpu.c                        |  19 --
> > >  target/sparc/gdbstub.c                    |  38 +++
> > >  target/xtensa/cpu.c                       |   2 +-
> > >  tests/qtest/test-hmp.c                    |   1 -
> > >  56 files changed, 1383 insertions(+), 478 deletions(-)
> > > ---
> > > base-commit: 8967b2fe1b2aaae3c29e207d85fab901d580a2dc
> > > change-id: 20260910-query-reg-80cd59cf4707
> > >
> > > Best regards,
> > > --
> > > Marc-André Lureau <marcandre.lureau@redhat.com>
> > >
> > --
> >  -----Open up your eyes, open up your mind, open up your code -------
> > / Dr. David Alan Gilbert    |       Running GNU/Linux       | Happy  \
> > \        dave @ treblig.org |                               | In Hex /
> >  \ _________________________|_____ http://www.treblig.org   |_______/
> >
-- 
 -----Open up your eyes, open up your mind, open up your code -------   
/ Dr. David Alan Gilbert    |       Running GNU/Linux       | Happy  \ 
\        dave @ treblig.org |                               | In Hex /
 \ _________________________|_____ http://www.treblig.org   |_______/