Re: [PATCH v2 3/5] gdbstub: Save target's siginfo

["Alex Bennée" <alex.bennee@linaro.org>]

Gustavo Romero <gustavo.romero@linaro.org> writes:

> Hi Alex,
>
> On 3/7/24 7:33 PM, Alex Bennée wrote:
>> Richard Henderson <richard.henderson@linaro.org> writes:
>> 
>>> On 3/7/24 08:26, Gustavo Romero wrote:
>>>> Save target's siginfo into gdbserver_state so it can be used later, for
>>>> example, in any stub that requires the target's si_signo and si_code.
>>>> This change affects only linux-user mode.
>>>> Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
>>>> Suggested-by: Richard Henderson <richard.henderson@linaro.org>
>>>> ---
>>>>    gdbstub/internals.h    |  3 +++
>>>>    gdbstub/user-target.c  |  3 ++-
>>>>    gdbstub/user.c         | 14 ++++++++++----
>>>>    include/gdbstub/user.h |  6 +++++-
>>>>    linux-user/main.c      |  2 +-
>>>>    linux-user/signal.c    |  5 ++++-
>>>>    6 files changed, 25 insertions(+), 8 deletions(-)
>>>> diff --git a/gdbstub/internals.h b/gdbstub/internals.h
>>>> index 56b7c13b75..a7cc69dab3 100644
>>>> --- a/gdbstub/internals.h
>>>> +++ b/gdbstub/internals.h
>>>> @@ -58,6 +58,9 @@ typedef struct GDBState {
>>>>        int line_csum; /* checksum at the end of the packet */
>>>>        GByteArray *last_packet;
>>>>        int signal;
>>>> +#ifdef CONFIG_USER_ONLY
>>>> +    uint8_t siginfo[MAX_SIGINFO_LENGTH];
>>>> +#endif
>>>
>>> If we this in GDBUserState in user.c -- no need for ifdefs then.
>> Although it does break on FreeBSD's user target:
>>    FAILED: libqemu-arm-bsd-user.fa.p/gdbstub_user-target.c.o
>>    cc -m64 -mcx16 -Ilibqemu-arm-bsd-user.fa.p -I. -I.. -Itarget/arm -I../target/arm -I../common-user/host/x86_64 -I../bsd-user/include -Ibsd-user/freebsd -I../bsd-user/freebsd -I../bsd-user/host/x86_64 -Ibsd-user -I../bsd-user -I../bsd-user/arm -Iqapi -Itrace -Iui -Iui/shader -I/usr/local/include/capstone -I/usr/local/include/glib-2.0 -I/usr/local/lib/glib-2.0/include -I/usr/local/include -fdiagnostics-color=auto -Wall -Winvalid-pch -Werror -std=gnu11 -O2 -g -fstack-protector-strong -Wempty-body -Wendif-labels -Wexpansion-to-defined -Wformat-security -Wformat-y2k -Wignored-qualifiers -Winit-self -Wmissing-format-attribute -Wmissing-prototypes -Wnested-externs -Wold-style-definition -Wredundant-decls -Wstrict-prototypes -Wtype-limits -Wundef -Wvla -Wwrite-strings -Wno-gnu-variable-sized-type-not-at-end -Wno-initializer-overrides -Wno-missing-include-dirs -Wno-psabi -Wno-shift-negative-value -Wno-string-plus-int -Wno-tautological-type-limit-compare -Wno-typedef-redefinition -Wthread-safety -iquote . -iquote /tmp/cirrus-ci-build -iquote /tmp/cirrus-ci-build/include -iquote /tmp/cirrus-ci-build/host/include/x86_64 -iquote /tmp/cirrus-ci-build/host/include/generic -iquote /tmp/cirrus-ci-build/tcg/i386 -pthread -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing -fno-common -fwrapv -ftrivial-auto-var-init=zero -fPIE -DNEED_CPU_H '-DCONFIG_TARGET="arm-bsd-user-config-target.h"' '-DCONFIG_DEVICES="arm-bsd-user-config-devices.h"' -MD -MQ libqemu-arm-bsd-user.fa.p/gdbstub_user-target.c.o -MF libqemu-arm-bsd-user.fa.p/gdbstub_user-target.c.o.d -o libqemu-arm-bsd-user.fa.p/gdbstub_user-target.c.o -c ../gdbstub/user-target.c
>>    In file included from ../gdbstub/user-target.c:18:
>>    ../gdbstub/internals.h:62:21: error: use of undeclared identifier 'MAX_SIGINFO_LENGTH'
>>       62 |     uint8_t siginfo[MAX_SIGINFO_LENGTH];
>>          |                     ^
>>    1 error generated.
>>    [2084/6731] Compiling C object libqemu-arm
>> See: https://gitlab.com/stsquad/qemu/-/jobs/6345829419
>
> argh, I've tested all targets for linux-user, but missed bsd-user. I've tried
> once to build it but that requires a BSD-like host, which I don't have at the
> moment, then I forgot about it... Let me setup one and review the change in
> the light of the comments from you and Richard.

  make vm-build-[open|net|free]bsd

see make vm-help for details.

>
> Thanks!
>
>
> Cheers,
> Gustavo

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro