qemu/accel
Luc Michel a7ba744f40 tcg/cpu-exec: precise single-stepping after an exception
When single-stepping with a debugger attached to QEMU, and when an
exception is raised, the debugger misses the first instruction after the
exception:

$ qemu-system-aarch64 -M virt -display none -cpu cortex-a53 -s -S

$ aarch64-linux-gnu-gdb
GNU gdb (GDB) 9.2
[...]
(gdb) tar rem :1234
Remote debugging using :1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x0000000000000000 in ?? ()
(gdb) # writing nop insns to 0x200 and 0x204
(gdb) set *0x200 = 0xd503201f
(gdb) set *0x204 = 0xd503201f
(gdb) # 0x0 address contains 0 which is an invalid opcode.
(gdb) # The CPU should raise an exception and jump to 0x200
(gdb) si
0x0000000000000204 in ?? ()

With this commit, the same run steps correctly on the first instruction
of the exception vector:

(gdb) si
0x0000000000000200 in ?? ()

Buglink: https://bugs.launchpad.net/qemu/+bug/757702
Signed-off-by: Luc Michel <luc.michel@greensocs.com>
Message-Id: <20200716193947.3058389-1-luc.michel@greensocs.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-07-16 14:08:29 -07:00
..
kvm error: Eliminate error_propagate() with Coccinelle, part 1 2020-07-10 15:18:08 +02:00
stubs accel/tcg: Add stub for probe_access() 2020-07-10 18:02:21 -04:00
tcg tcg/cpu-exec: precise single-stepping after an exception 2020-07-16 14:08:29 -07:00
xen xen: fix build without pci passthrough 2020-06-12 11:20:12 -04:00
accel.c accel: Introduce the current_accel() wrapper 2020-01-24 20:59:11 +01:00
Kconfig accel/Kconfig: Add the TCG selector 2020-07-10 18:02:21 -04:00
Makefile.objs accel: Move Xen accelerator code under accel/xen/ 2020-06-10 12:09:56 -04:00
qtest.c qtest: Don't compile qtest accel on non-POSIX systems 2019-05-02 16:56:33 +02:00