Our current setup is:
host_signal_handler
cpu_signal_handler
handle_cpu_signal
cc->tcg_ops->tlb_fill
raise_exception
cpu_loop
queue_signal
and in the process lose information from the host siginfo_t,
which we (mostly) do not recreate properly. Moreover, the
intermediate cpu_signal_handler handles the host-specific
portions of extracting pc + is_write from the ucontext_t.
I'm replacing this with
host_signal_handler
host_signal_pc
host_sigsegv_write
adjust_signal_pc
handle_sigsegv_accerr_write
queue_signal
raise_exception
cpu_loop
All of the really tcg-specific portions are still in user-exec.c,
and all of the really host-specific portions are now ditributed
across linux-user/host//. Importantly, SEGV_MAPERR and
SEGV_ACCERR are now passed through from the host kernel -- or at
least there's a single place from which to manage it [1].
Note that I've dropped all of the BSD (and Solaris!) code from
user-exec.c. I thought about moving it similar to linux-user,
but I've caught Warner in the middle of his re-org and the whole
of bsd-user/signal.c is currently empty. I think it will be
easier to create the new interfaces from scratch when ready.
Still to-do:
* Make cc->tcg_ops->tlb_fill sysemu only (once again).
* Drop all of the code from cpu_loop that interfaced with tlb_fill.
r~
[1] I've just this minute realized that the reserved_va mapping that we
do for emulating 32-bit guests will incorrectly give SEGV_ACCERR for pages
that are not mapped by the guest, and should result in SEGV_MAPERR.
Richard Henderson (7):
include/exec: Move cpu_signal_handler declaration
accel/tcg: Split out adjust_signal_pc
accel/tcg: Split out handle_sigsegv_accerr_write
accel/tcg: Move clear_helper_retaddr to cpu loop
accel/tcg: Fold cpu_exit_tb_from_sighandler into caller
linux-user: Handle SIGSEGV/SIGBUS in host_to_target_siginfo_noswap
linux-user: Reorg cpu_signal_handler
include/exec/exec-all.h | 21 +
linux-user/host/aarch64/host-signal.h | 73 +++
linux-user/host/alpha/host-signal.h | 41 ++
linux-user/host/arm/host-signal.h | 30 +
linux-user/host/i386/host-signal.h| 24 +
linux-user/host/mips/host-signal.h| 61 ++
linux-user/host/ppc/host-signal.h | 24 +
linux-user/host/ppc64/host-signal.h | 1 +
linux-user/host/riscv32/host-signal.h | 57 ++
linux-user/host/riscv64/host-signal.h | 1 +
linux-user/host/s390/host-signal.h| 92 +++
linux-user/host/s390x/host-signal.h | 1 +
linux-user/host/sparc/host-signal.h | 53 ++
linux-user/host/sparc64/host-signal.h | 1 +
linux-user/host/x86_64/host-signal.h | 24 +
target/alpha/cpu.h| 6 -
target/arm/cpu.h | 7 -
target/avr/cpu.h | 2 -
target/cris/cpu.h | 8 -
target/hexagon/cpu.h | 3 -
target/hppa/cpu.h | 3 -
target/i386/cpu.h | 7 -
target/m68k/cpu.h | 8 -
target/microblaze/cpu.h | 7 -
target/mips/cpu.h | 3 -
target/mips/internal.h| 2 -
target/nios2/cpu.h| 2 -
target/openrisc/cpu.h | 2 -
target/ppc/cpu.h | 7 -
target/riscv/cpu.h| 2 -
target/rx/cpu.h | 4 -
target/s390x/cpu.h| 7 -
target/sh4/cpu.h | 3 -
target/sparc/cpu.h| 2 -
target/tricore/cpu.h | 2 -
target/xtensa/cpu.h | 2 -
accel/tcg/cpu-exec.c | 3 +-
accel/tcg/user-exec.c | 807 ++
linux-user/signal.c | 102 ++--
39 files changed, 635 insertions(+), 870 deletions(-)
create mode 100644 linux-user/host/aarch64/host-signal.h
create mode 100644 linux-user/host/alpha/host-signal.h
create mode 100644 linux-user/host/arm/host-signal.h
create mode 100644 linux-user/host/i386/host-signal.h
create mode 100644 linux-user/host/mips/host-signal.h
create mode 100644 linux-user/host/ppc/host-signal.h
create mode 100644 linux-user/host/ppc64/host-signal.h
create mode 100644 linux-user/host/riscv32/host-signal.h
create mode 100644 linux-user/host/riscv64/host-signal.h
create mode 100644 linux-user/host/s390/host-signal.h
create mode 100644 linux-user/host/s390x/host-signal.h
create mode 100644 linux-user/host/sparc/host-signal.h
create mode 100644 linux-user/host/sparc64/host-signal.h
create mode 100644 linux-user/host/x86_64/host-signal.h
--
2.25.1
