From 578774c09a89dd1e3023677aad5ebb7a3562c8ba Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Sat, 9 Mar 2024 11:56:02 +0000 Subject: [PATCH 1/7] tests/vm: ensure we build everything by default MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The "check" target by itself is not enough to ensure we build the user mode binaries. While we can't test them with check-tcg we can at least include them in the build. Signed-off-by: Alex Bennée Reviewed-by: Thomas Huth Cc: Richard Henderson Cc: Gustavo Romero --- tests/vm/basevm.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py index f8fd751eb1..4a1af04b9a 100644 --- a/tests/vm/basevm.py +++ b/tests/vm/basevm.py @@ -606,7 +606,7 @@ def parse_args(vmcls): parser.add_argument("--build-qemu", help="build QEMU from source in guest") parser.add_argument("--build-target", - help="QEMU build target", default="check") + help="QEMU build target", default="all check") parser.add_argument("--build-path", default=None, help="Path of build directory, "\ "for using build tree QEMU binary. ") From b6617e937e9abe6ce449729e2fdebf11014f7e49 Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Sat, 9 Mar 2024 03:08:57 +0000 Subject: [PATCH 2/7] gdbstub: Rename back gdb_handlesig MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Rename gdb_handlesig_reason back to gdb_handlesig. There is no need to add a wrapper for gdb_handlesig and rename it when a new parameter is added. Signed-off-by: Gustavo Romero Reviewed-by: Alex Bennée Reviewed-by: Richard Henderson Message-Id: <20240309030901.1726211-2-gustavo.romero@linaro.org> Signed-off-by: Alex Bennée --- gdbstub/user.c | 8 ++++---- include/gdbstub/user.h | 15 ++------------- linux-user/main.c | 2 +- linux-user/signal.c | 2 +- 4 files changed, 8 insertions(+), 19 deletions(-) diff --git a/gdbstub/user.c b/gdbstub/user.c index 7f9f19a124..520987fddc 100644 --- a/gdbstub/user.c +++ b/gdbstub/user.c @@ -190,7 +190,7 @@ void gdb_qemu_exit(int code) exit(code); } -int gdb_handlesig_reason(CPUState *cpu, int sig, const char *reason) +int gdb_handlesig(CPUState *cpu, int sig, const char *reason) { char buf[256]; int n; @@ -746,7 +746,7 @@ void gdb_breakpoint_remove_all(CPUState *cs) void gdb_syscall_handling(const char *syscall_packet) { gdb_put_packet(syscall_packet); - gdb_handlesig(gdbserver_state.c_cpu, 0); + gdb_handlesig(gdbserver_state.c_cpu, 0, NULL); } static bool should_catch_syscall(int num) @@ -764,7 +764,7 @@ void gdb_syscall_entry(CPUState *cs, int num) { if (should_catch_syscall(num)) { g_autofree char *reason = g_strdup_printf("syscall_entry:%x;", num); - gdb_handlesig_reason(cs, gdb_target_sigtrap(), reason); + gdb_handlesig(cs, gdb_target_sigtrap(), reason); } } @@ -772,7 +772,7 @@ void gdb_syscall_return(CPUState *cs, int num) { if (should_catch_syscall(num)) { g_autofree char *reason = g_strdup_printf("syscall_return:%x;", num); - gdb_handlesig_reason(cs, gdb_target_sigtrap(), reason); + gdb_handlesig(cs, gdb_target_sigtrap(), reason); } } diff --git a/include/gdbstub/user.h b/include/gdbstub/user.h index 4c4e5c4c58..4fc88f8a25 100644 --- a/include/gdbstub/user.h +++ b/include/gdbstub/user.h @@ -10,7 +10,7 @@ #define GDBSTUB_USER_H /** - * gdb_handlesig_reason() - yield control to gdb + * gdb_handlesig() - yield control to gdb * @cpu: CPU * @sig: if non-zero, the signal number which caused us to stop * @reason: stop reason for stop reply packet or NULL @@ -25,18 +25,7 @@ * or 0 if no signal should be delivered, ie the signal that caused * us to stop should be ignored. */ -int gdb_handlesig_reason(CPUState *, int, const char *); - -/** - * gdb_handlesig() - yield control to gdb - * @cpu CPU - * @sig: if non-zero, the signal number which caused us to stop - * @see gdb_handlesig_reason() - */ -static inline int gdb_handlesig(CPUState *cpu, int sig) -{ - return gdb_handlesig_reason(cpu, sig, NULL); -} +int gdb_handlesig(CPUState *, int, const char *); /** * gdb_signalled() - inform remote gdb of sig exit diff --git a/linux-user/main.c b/linux-user/main.c index 41caa77cb5..55aa11c9b4 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -1018,7 +1018,7 @@ int main(int argc, char **argv, char **envp) gdbstub); exit(EXIT_FAILURE); } - gdb_handlesig(cpu, 0); + gdb_handlesig(cpu, 0, NULL); } #ifdef CONFIG_SEMIHOSTING diff --git a/linux-user/signal.c b/linux-user/signal.c index 1aebf3fc47..b705625cbd 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -1178,7 +1178,7 @@ static void handle_pending_signal(CPUArchState *cpu_env, int sig, /* dequeue signal */ k->pending = 0; - sig = gdb_handlesig(cpu, sig); + sig = gdb_handlesig(cpu, sig, NULL); if (!sig) { sa = NULL; handler = TARGET_SIG_IGN; From 4d6d8a05a0a6d102ca94e59a43804d65309921e3 Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Sat, 9 Mar 2024 03:08:58 +0000 Subject: [PATCH 3/7] linux-user: Move tswap_siginfo out of target code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Move tswap_siginfo from target code to handle_pending_signal. This will allow some cleanups and having the siginfo ready to be used in gdbstub. Signed-off-by: Gustavo Romero Suggested-by: Richard Henderson Reviewed-by: Richard Henderson Message-Id: <20240309030901.1726211-3-gustavo.romero@linaro.org> Signed-off-by: Alex Bennée --- linux-user/aarch64/signal.c | 2 +- linux-user/alpha/signal.c | 2 +- linux-user/arm/signal.c | 2 +- linux-user/hexagon/signal.c | 2 +- linux-user/hppa/signal.c | 2 +- linux-user/i386/signal.c | 6 +++--- linux-user/loongarch64/signal.c | 2 +- linux-user/m68k/signal.c | 4 ++-- linux-user/microblaze/signal.c | 2 +- linux-user/mips/signal.c | 4 ++-- linux-user/nios2/signal.c | 2 +- linux-user/openrisc/signal.c | 2 +- linux-user/ppc/signal.c | 4 ++-- linux-user/riscv/signal.c | 2 +- linux-user/s390x/signal.c | 2 +- linux-user/sh4/signal.c | 2 +- linux-user/signal-common.h | 2 -- linux-user/signal.c | 10 ++++++++-- linux-user/sparc/signal.c | 2 +- linux-user/xtensa/signal.c | 2 +- 20 files changed, 31 insertions(+), 27 deletions(-) diff --git a/linux-user/aarch64/signal.c b/linux-user/aarch64/signal.c index a1e22d526d..bc7a13800d 100644 --- a/linux-user/aarch64/signal.c +++ b/linux-user/aarch64/signal.c @@ -670,7 +670,7 @@ static void target_setup_frame(int usig, struct target_sigaction *ka, aarch64_set_svcr(env, 0, R_SVCR_SM_MASK | R_SVCR_ZA_MASK); if (info) { - tswap_siginfo(&frame->info, info); + frame->info = *info; env->xregs[1] = frame_addr + offsetof(struct target_rt_sigframe, info); env->xregs[2] = frame_addr + offsetof(struct target_rt_sigframe, uc); } diff --git a/linux-user/alpha/signal.c b/linux-user/alpha/signal.c index 4ec42994d4..896c2c148a 100644 --- a/linux-user/alpha/signal.c +++ b/linux-user/alpha/signal.c @@ -173,7 +173,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, goto give_sigsegv; } - tswap_siginfo(&frame->info, info); + frame->info = *info; __put_user(0, &frame->uc.tuc_flags); __put_user(0, &frame->uc.tuc_link); diff --git a/linux-user/arm/signal.c b/linux-user/arm/signal.c index 59806335f5..8db1c4b233 100644 --- a/linux-user/arm/signal.c +++ b/linux-user/arm/signal.c @@ -357,7 +357,7 @@ void setup_rt_frame(int usig, struct target_sigaction *ka, info_addr = frame_addr + offsetof(struct rt_sigframe, info); uc_addr = frame_addr + offsetof(struct rt_sigframe, sig.uc); - tswap_siginfo(&frame->info, info); + frame->info = *info; setup_sigframe(&frame->sig.uc, set, env); diff --git a/linux-user/hexagon/signal.c b/linux-user/hexagon/signal.c index 60fa7e1bce..492b51f155 100644 --- a/linux-user/hexagon/signal.c +++ b/linux-user/hexagon/signal.c @@ -162,7 +162,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } setup_ucontext(&frame->uc, env, set); - tswap_siginfo(&frame->info, info); + frame->info = *info; /* * The on-stack signal trampoline is no longer executed; * however, the libgcc signal frame unwinding code checks diff --git a/linux-user/hppa/signal.c b/linux-user/hppa/signal.c index c84557e906..682ba25922 100644 --- a/linux-user/hppa/signal.c +++ b/linux-user/hppa/signal.c @@ -127,7 +127,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, goto give_sigsegv; } - tswap_siginfo(&frame->info, info); + frame->info = *info; frame->uc.tuc_flags = 0; frame->uc.tuc_link = 0; diff --git a/linux-user/i386/signal.c b/linux-user/i386/signal.c index bc5d45302e..cfe70fc5cf 100644 --- a/linux-user/i386/signal.c +++ b/linux-user/i386/signal.c @@ -430,7 +430,7 @@ void setup_frame(int sig, struct target_sigaction *ka, setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0], frame_addr + offsetof(struct sigframe, fpstate)); - for(i = 1; i < TARGET_NSIG_WORDS; i++) { + for (i = 1; i < TARGET_NSIG_WORDS; i++) { __put_user(set->sig[i], &frame->extramask[i - 1]); } @@ -490,7 +490,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, __put_user(addr, &frame->puc); #endif if (ka->sa_flags & TARGET_SA_SIGINFO) { - tswap_siginfo(&frame->info, info); + frame->info = *info; } /* Create the ucontext. */ @@ -504,7 +504,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, setup_sigcontext(&frame->uc.tuc_mcontext, &frame->fpstate, env, set->sig[0], frame_addr + offsetof(struct rt_sigframe, fpstate)); - for(i = 0; i < TARGET_NSIG_WORDS; i++) { + for (i = 0; i < TARGET_NSIG_WORDS; i++) { __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]); } diff --git a/linux-user/loongarch64/signal.c b/linux-user/loongarch64/signal.c index 39ea82c814..1a322f9697 100644 --- a/linux-user/loongarch64/signal.c +++ b/linux-user/loongarch64/signal.c @@ -376,7 +376,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, extctx.end.haddr = (void *)frame + (extctx.end.gaddr - frame_addr); } - tswap_siginfo(&frame->rs_info, info); + frame->rs_info = *info; __put_user(0, &frame->rs_uc.tuc_flags); __put_user(0, &frame->rs_uc.tuc_link); diff --git a/linux-user/m68k/signal.c b/linux-user/m68k/signal.c index 5f35354487..77555781aa 100644 --- a/linux-user/m68k/signal.c +++ b/linux-user/m68k/signal.c @@ -295,7 +295,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, uc_addr = frame_addr + offsetof(struct target_rt_sigframe, uc); __put_user(uc_addr, &frame->puc); - tswap_siginfo(&frame->info, info); + frame->info = *info; /* Create the ucontext */ @@ -307,7 +307,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, if (err) goto give_sigsegv; - for(i = 0; i < TARGET_NSIG_WORDS; i++) { + for (i = 0; i < TARGET_NSIG_WORDS; i++) { __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]); } diff --git a/linux-user/microblaze/signal.c b/linux-user/microblaze/signal.c index 5188d74025..f6d47d76ff 100644 --- a/linux-user/microblaze/signal.c +++ b/linux-user/microblaze/signal.c @@ -147,7 +147,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, return; } - tswap_siginfo(&frame->info, info); + frame->info = *info; __put_user(0, &frame->uc.tuc_flags); __put_user(0, &frame->uc.tuc_link); diff --git a/linux-user/mips/signal.c b/linux-user/mips/signal.c index 58a9d7a8a3..d69a5d73dd 100644 --- a/linux-user/mips/signal.c +++ b/linux-user/mips/signal.c @@ -303,7 +303,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, goto give_sigsegv; } - tswap_siginfo(&frame->rs_info, info); + frame->rs_info = *info; __put_user(0, &frame->rs_uc.tuc_flags); __put_user(0, &frame->rs_uc.tuc_link); @@ -311,7 +311,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, setup_sigcontext(env, &frame->rs_uc.tuc_mcontext); - for(i = 0; i < TARGET_NSIG_WORDS; i++) { + for (i = 0; i < TARGET_NSIG_WORDS; i++) { __put_user(set->sig[i], &frame->rs_uc.tuc_sigmask.sig[i]); } diff --git a/linux-user/nios2/signal.c b/linux-user/nios2/signal.c index 32b3dc99c6..64c345f409 100644 --- a/linux-user/nios2/signal.c +++ b/linux-user/nios2/signal.c @@ -157,7 +157,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, return; } - tswap_siginfo(&frame->info, info); + frame->info = *info; /* Create the ucontext. */ __put_user(0, &frame->uc.tuc_flags); diff --git a/linux-user/openrisc/signal.c b/linux-user/openrisc/signal.c index be8b68784a..cb74a9fe5e 100644 --- a/linux-user/openrisc/signal.c +++ b/linux-user/openrisc/signal.c @@ -103,7 +103,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } if (ka->sa_flags & SA_SIGINFO) { - tswap_siginfo(&frame->info, info); + frame->info = *info; } __put_user(0, &frame->uc.tuc_flags); diff --git a/linux-user/ppc/signal.c b/linux-user/ppc/signal.c index c232424c1e..652038a53c 100644 --- a/linux-user/ppc/signal.c +++ b/linux-user/ppc/signal.c @@ -493,7 +493,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, if (!lock_user_struct(VERIFY_WRITE, rt_sf, rt_sf_addr, 1)) goto sigsegv; - tswap_siginfo(&rt_sf->info, info); + rt_sf->info = *info; __put_user(0, &rt_sf->uc.tuc_flags); __put_user(0, &rt_sf->uc.tuc_link); @@ -502,7 +502,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, __put_user(h2g (&rt_sf->uc.tuc_mcontext), &rt_sf->uc.tuc_regs); #endif - for(i = 0; i < TARGET_NSIG_WORDS; i++) { + for (i = 0; i < TARGET_NSIG_WORDS; i++) { __put_user(set->sig[i], &rt_sf->uc.tuc_sigmask.sig[i]); } diff --git a/linux-user/riscv/signal.c b/linux-user/riscv/signal.c index 941eadce87..358fa1d82d 100644 --- a/linux-user/riscv/signal.c +++ b/linux-user/riscv/signal.c @@ -125,7 +125,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } setup_ucontext(&frame->uc, env, set); - tswap_siginfo(&frame->info, info); + frame->info = *info; env->pc = ka->_sa_handler; env->gpr[xSP] = frame_addr; diff --git a/linux-user/s390x/signal.c b/linux-user/s390x/signal.c index b40f738a70..df49c24708 100644 --- a/linux-user/s390x/signal.c +++ b/linux-user/s390x/signal.c @@ -267,7 +267,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } /* Create siginfo on the signal stack. */ - tswap_siginfo(&frame->info, info); + frame->info = *info; /* Create ucontext on the signal stack. */ uc_flags = 0; diff --git a/linux-user/sh4/signal.c b/linux-user/sh4/signal.c index c16c2c2d57..9ecc026fae 100644 --- a/linux-user/sh4/signal.c +++ b/linux-user/sh4/signal.c @@ -233,7 +233,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, goto give_sigsegv; } - tswap_siginfo(&frame->info, info); + frame->info = *info; /* Create the ucontext. */ __put_user(0, &frame->uc.tuc_flags); diff --git a/linux-user/signal-common.h b/linux-user/signal-common.h index a7df12fc44..f4cbe6185e 100644 --- a/linux-user/signal-common.h +++ b/linux-user/signal-common.h @@ -43,8 +43,6 @@ void host_to_target_sigset_internal(target_sigset_t *d, const sigset_t *s); void target_to_host_sigset_internal(sigset_t *d, const target_sigset_t *s); -void tswap_siginfo(target_siginfo_t *tinfo, - const target_siginfo_t *info); void set_sigmask(const sigset_t *set); void force_sig(int sig); void force_sigsegv(int oldsig); diff --git a/linux-user/signal.c b/linux-user/signal.c index b705625cbd..2db4d12ef6 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -409,8 +409,8 @@ static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo, tinfo->si_code = deposit32(si_code, 16, 16, si_type); } -void tswap_siginfo(target_siginfo_t *tinfo, - const target_siginfo_t *info) +static void tswap_siginfo(target_siginfo_t *tinfo, + const target_siginfo_t *info) { int si_type = extract32(info->si_code, 16, 16); int si_code = sextract32(info->si_code, 0, 16); @@ -1178,6 +1178,12 @@ static void handle_pending_signal(CPUArchState *cpu_env, int sig, /* dequeue signal */ k->pending = 0; + /* + * Writes out siginfo values byteswapped, accordingly to the target. It also + * cleans the si_type from si_code making it correct for the target. + */ + tswap_siginfo(&k->info, &k->info); + sig = gdb_handlesig(cpu, sig, NULL); if (!sig) { sa = NULL; diff --git a/linux-user/sparc/signal.c b/linux-user/sparc/signal.c index c2dc1000e2..f164b74032 100644 --- a/linux-user/sparc/signal.c +++ b/linux-user/sparc/signal.c @@ -333,7 +333,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, __put_user(0, &sf->rwin_save); /* TODO: save_rwin_state */ - tswap_siginfo(&sf->info, info); + sf->info = *info; tswap_sigset(&sf->mask, set); target_save_altstack(&sf->stack, env); diff --git a/linux-user/xtensa/signal.c b/linux-user/xtensa/signal.c index 003208a916..6514b8dd57 100644 --- a/linux-user/xtensa/signal.c +++ b/linux-user/xtensa/signal.c @@ -184,7 +184,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, } if (ka->sa_flags & SA_SIGINFO) { - tswap_siginfo(&frame->info, info); + frame->info = *info; } __put_user(0, &frame->uc.tuc_flags); From f84e313e0278222eb88b9ca29311f0df71abd001 Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Sat, 9 Mar 2024 03:08:59 +0000 Subject: [PATCH 4/7] gdbstub: Save target's siginfo MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Suggested-by: Richard Henderson Message-Id: <20240309030901.1726211-4-gustavo.romero@linaro.org> Signed-off-by: Alex Bennée Reviewed-by: Richard Henderson --- bsd-user/main.c | 2 +- bsd-user/signal.c | 5 ++++- gdbstub/user.c | 23 +++++++++++++++++++---- include/gdbstub/user.h | 6 +++++- linux-user/main.c | 2 +- linux-user/signal.c | 5 ++++- 6 files changed, 34 insertions(+), 9 deletions(-) diff --git a/bsd-user/main.c b/bsd-user/main.c index 3dc285e5b7..01b313756e 100644 --- a/bsd-user/main.c +++ b/bsd-user/main.c @@ -606,7 +606,7 @@ int main(int argc, char **argv) if (gdbstub) { gdbserver_start(gdbstub); - gdb_handlesig(cpu, 0); + gdb_handlesig(cpu, 0, NULL, NULL, 0); } cpu_loop(env); /* never exits */ diff --git a/bsd-user/signal.c b/bsd-user/signal.c index 3ac50c2d71..e5a773ddde 100644 --- a/bsd-user/signal.c +++ b/bsd-user/signal.c @@ -27,6 +27,9 @@ #include "hw/core/tcg-cpu-ops.h" #include "host-signal.h" +/* target_siginfo_t must fit in gdbstub's siginfo save area. */ +QEMU_BUILD_BUG_ON(sizeof(target_siginfo_t) > MAX_SIGINFO_LENGTH); + static struct target_sigaction sigact_table[TARGET_NSIG]; static void host_signal_handler(int host_sig, siginfo_t *info, void *puc); static void target_to_host_sigset_internal(sigset_t *d, @@ -889,7 +892,7 @@ static void handle_pending_signal(CPUArchState *env, int sig, k->pending = 0; - sig = gdb_handlesig(cpu, sig); + sig = gdb_handlesig(cpu, sig, NULL, &k->info, sizeof(k->info)); if (!sig) { sa = NULL; handler = TARGET_SIG_IGN; diff --git a/gdbstub/user.c b/gdbstub/user.c index 520987fddc..cf693bfbc4 100644 --- a/gdbstub/user.c +++ b/gdbstub/user.c @@ -95,6 +95,8 @@ typedef struct { enum GDBForkState fork_state; int fork_sockets[2]; pid_t fork_peer_pid, fork_peer_tid; + uint8_t siginfo[MAX_SIGINFO_LENGTH]; + unsigned long siginfo_len; } GDBUserState; static GDBUserState gdbserver_user_state; @@ -190,7 +192,8 @@ void gdb_qemu_exit(int code) exit(code); } -int gdb_handlesig(CPUState *cpu, int sig, const char *reason) +int gdb_handlesig(CPUState *cpu, int sig, const char *reason, void *siginfo, + int siginfo_len) { char buf[256]; int n; @@ -199,6 +202,18 @@ int gdb_handlesig(CPUState *cpu, int sig, const char *reason) return sig; } + if (siginfo) { + /* + * Save target-specific siginfo. + * + * siginfo size, i.e. siginfo_len, is asserted at compile-time to fit in + * gdbserver_user_state.siginfo, usually in the source file calling + * gdb_handlesig. See, for instance, {linux,bsd}-user/signal.c. + */ + memcpy(gdbserver_user_state.siginfo, siginfo, siginfo_len); + gdbserver_user_state.siginfo_len = siginfo_len; + } + /* disable single step if it was enabled */ cpu_single_step(cpu, 0); tb_flush(cpu); @@ -746,7 +761,7 @@ void gdb_breakpoint_remove_all(CPUState *cs) void gdb_syscall_handling(const char *syscall_packet) { gdb_put_packet(syscall_packet); - gdb_handlesig(gdbserver_state.c_cpu, 0, NULL); + gdb_handlesig(gdbserver_state.c_cpu, 0, NULL, NULL, 0); } static bool should_catch_syscall(int num) @@ -764,7 +779,7 @@ void gdb_syscall_entry(CPUState *cs, int num) { if (should_catch_syscall(num)) { g_autofree char *reason = g_strdup_printf("syscall_entry:%x;", num); - gdb_handlesig(cs, gdb_target_sigtrap(), reason); + gdb_handlesig(cs, gdb_target_sigtrap(), reason, NULL, 0); } } @@ -772,7 +787,7 @@ void gdb_syscall_return(CPUState *cs, int num) { if (should_catch_syscall(num)) { g_autofree char *reason = g_strdup_printf("syscall_return:%x;", num); - gdb_handlesig(cs, gdb_target_sigtrap(), reason); + gdb_handlesig(cs, gdb_target_sigtrap(), reason, NULL, 0); } } diff --git a/include/gdbstub/user.h b/include/gdbstub/user.h index 4fc88f8a25..3b8358e3da 100644 --- a/include/gdbstub/user.h +++ b/include/gdbstub/user.h @@ -9,11 +9,15 @@ #ifndef GDBSTUB_USER_H #define GDBSTUB_USER_H +#define MAX_SIGINFO_LENGTH 128 + /** * gdb_handlesig() - yield control to gdb * @cpu: CPU * @sig: if non-zero, the signal number which caused us to stop * @reason: stop reason for stop reply packet or NULL + * @siginfo: target-specific siginfo struct + * @siginfo_len: target-specific siginfo struct length * * This function yields control to gdb, when a user-mode-only target * needs to stop execution. If @sig is non-zero, then we will send a @@ -25,7 +29,7 @@ * or 0 if no signal should be delivered, ie the signal that caused * us to stop should be ignored. */ -int gdb_handlesig(CPUState *, int, const char *); +int gdb_handlesig(CPUState *, int, const char *, void *, int); /** * gdb_signalled() - inform remote gdb of sig exit diff --git a/linux-user/main.c b/linux-user/main.c index 55aa11c9b4..9277df2e9d 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -1018,7 +1018,7 @@ int main(int argc, char **argv, char **envp) gdbstub); exit(EXIT_FAILURE); } - gdb_handlesig(cpu, 0, NULL); + gdb_handlesig(cpu, 0, NULL, NULL, 0); } #ifdef CONFIG_SEMIHOSTING diff --git a/linux-user/signal.c b/linux-user/signal.c index 2db4d12ef6..a93148a4cb 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -34,6 +34,9 @@ #include "user/safe-syscall.h" #include "tcg/tcg.h" +/* target_siginfo_t must fit in gdbstub's siginfo save area. */ +QEMU_BUILD_BUG_ON(sizeof(target_siginfo_t) > MAX_SIGINFO_LENGTH); + static struct target_sigaction sigact_table[TARGET_NSIG]; static void host_signal_handler(int host_signum, siginfo_t *info, @@ -1184,7 +1187,7 @@ static void handle_pending_signal(CPUArchState *cpu_env, int sig, */ tswap_siginfo(&k->info, &k->info); - sig = gdb_handlesig(cpu, sig, NULL); + sig = gdb_handlesig(cpu, sig, NULL, &k->info, sizeof(k->info)); if (!sig) { sa = NULL; handler = TARGET_SIG_IGN; From 9ae5801d35b5228583dfcdb9c76cf2c6f4566215 Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Sat, 9 Mar 2024 03:09:00 +0000 Subject: [PATCH 5/7] gdbstub: Add Xfer:siginfo:read stub MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add stub to handle Xfer:siginfo:read packet query that requests the machine's siginfo data. This is used when GDB user executes 'print $_siginfo' and when the machine stops due to a signal, for instance, on SIGSEGV. The information in siginfo allows GDB to determiner further details on the signal, like the fault address/insn when the SIGSEGV is caught. Signed-off-by: Gustavo Romero Message-Id: <20240309030901.1726211-5-gustavo.romero@linaro.org> Signed-off-by: Alex Bennée Reviewed-by: Richard Henderson --- gdbstub/gdbstub.c | 8 ++++++++ gdbstub/internals.h | 1 + gdbstub/user.c | 23 +++++++++++++++++++++++ 3 files changed, 32 insertions(+) diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c index 17efcae0d0..9c23d44baf 100644 --- a/gdbstub/gdbstub.c +++ b/gdbstub/gdbstub.c @@ -1664,6 +1664,8 @@ static void handle_query_supported(GArray *params, void *user_ctx) g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+"); } g_string_append(gdbserver_state.str_buf, ";QCatchSyscalls+"); + + g_string_append(gdbserver_state.str_buf, ";qXfer:siginfo:read+"); #endif g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+"); #endif @@ -1818,6 +1820,12 @@ static const GdbCmdParseEntry gdb_gen_query_table[] = { .cmd_startswith = 1, .schema = "l,l0" }, + { + .handler = gdb_handle_query_xfer_siginfo, + .cmd = "Xfer:siginfo:read::", + .cmd_startswith = 1, + .schema = "l,l0" + }, #endif { .handler = gdb_handle_query_xfer_exec_file, diff --git a/gdbstub/internals.h b/gdbstub/internals.h index b472459838..e83b179920 100644 --- a/gdbstub/internals.h +++ b/gdbstub/internals.h @@ -190,6 +190,7 @@ typedef union GdbCmdVariant { void gdb_handle_query_rcmd(GArray *params, void *user_ctx); /* softmmu */ void gdb_handle_query_offsets(GArray *params, void *user_ctx); /* user */ void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx); /*user */ +void gdb_handle_query_xfer_siginfo(GArray *params, void *user_ctx); /*user */ void gdb_handle_v_file_open(GArray *params, void *user_ctx); /* user */ void gdb_handle_v_file_close(GArray *params, void *user_ctx); /* user */ void gdb_handle_v_file_pread(GArray *params, void *user_ctx); /* user */ diff --git a/gdbstub/user.c b/gdbstub/user.c index cf693bfbc4..2005f3312b 100644 --- a/gdbstub/user.c +++ b/gdbstub/user.c @@ -852,3 +852,26 @@ void gdb_handle_set_catch_syscalls(GArray *params, void *user_ctx) err: gdb_put_packet("E00"); } + +void gdb_handle_query_xfer_siginfo(GArray *params, void *user_ctx) +{ + unsigned long offset, len; + uint8_t *siginfo_offset; + + offset = get_param(params, 0)->val_ul; + len = get_param(params, 1)->val_ul; + + if (offset + len > gdbserver_user_state.siginfo_len) { + /* Invalid offset and/or requested length. */ + gdb_put_packet("E01"); + return; + } + + siginfo_offset = (uint8_t *)gdbserver_user_state.siginfo + offset; + + /* Reply */ + g_string_assign(gdbserver_state.str_buf, "l"); + gdb_memtox(gdbserver_state.str_buf, (const char *)siginfo_offset, len); + gdb_put_packet_binary(gdbserver_state.str_buf->str, + gdbserver_state.str_buf->len, true); +} From bbc0543b1b8231eb9712aa9b93091a1ccb2a08cd Mon Sep 17 00:00:00 2001 From: Gustavo Romero Date: Sat, 9 Mar 2024 03:09:01 +0000 Subject: [PATCH 6/7] tests/tcg: Add multiarch test for Xfer:siginfo:read stub MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add multiarch test for testing if Xfer:siginfo:read query is properly handled by gdbstub. Signed-off-by: Gustavo Romero Reviewed-by: Richard Henderson Message-Id: <20240309030901.1726211-6-gustavo.romero@linaro.org> Signed-off-by: Alex Bennée --- tests/tcg/multiarch/Makefile.target | 10 ++++++- .../gdbstub/test-qxfer-siginfo-read.py | 26 +++++++++++++++++++ tests/tcg/multiarch/segfault.c | 14 ++++++++++ 3 files changed, 49 insertions(+), 1 deletion(-) create mode 100644 tests/tcg/multiarch/gdbstub/test-qxfer-siginfo-read.py create mode 100644 tests/tcg/multiarch/segfault.c diff --git a/tests/tcg/multiarch/Makefile.target b/tests/tcg/multiarch/Makefile.target index 979a0dd1bc..5e3391ec9d 100644 --- a/tests/tcg/multiarch/Makefile.target +++ b/tests/tcg/multiarch/Makefile.target @@ -71,6 +71,13 @@ run-gdbstub-qxfer-auxv-read: sha1 --bin $< --test $(MULTIARCH_SRC)/gdbstub/test-qxfer-auxv-read.py, \ basic gdbstub qXfer:auxv:read support) +run-gdbstub-qxfer-siginfo-read: segfault + $(call run-test, $@, $(GDB_SCRIPT) \ + --gdb $(GDB) \ + --qemu $(QEMU) --qargs "$(QEMU_OPTS)" \ + --bin "$< -s" --test $(MULTIARCH_SRC)/gdbstub/test-qxfer-siginfo-read.py, \ + basic gdbstub qXfer:siginfo:read support) + run-gdbstub-proc-mappings: sha1 $(call run-test, $@, $(GDB_SCRIPT) \ --gdb $(GDB) \ @@ -128,7 +135,8 @@ EXTRA_RUNS += run-gdbstub-sha1 run-gdbstub-qxfer-auxv-read \ run-gdbstub-proc-mappings run-gdbstub-thread-breakpoint \ run-gdbstub-registers run-gdbstub-prot-none \ run-gdbstub-catch-syscalls run-gdbstub-follow-fork-mode-child \ - run-gdbstub-follow-fork-mode-parent + run-gdbstub-follow-fork-mode-parent \ + run-gdbstub-qxfer-siginfo-read # ARM Compatible Semi Hosting Tests # diff --git a/tests/tcg/multiarch/gdbstub/test-qxfer-siginfo-read.py b/tests/tcg/multiarch/gdbstub/test-qxfer-siginfo-read.py new file mode 100644 index 0000000000..862596b07a --- /dev/null +++ b/tests/tcg/multiarch/gdbstub/test-qxfer-siginfo-read.py @@ -0,0 +1,26 @@ +from __future__ import print_function +# +# Test gdbstub Xfer:siginfo:read stub. +# +# The test runs a binary that causes a SIGSEGV and then looks for additional +# info about the signal through printing GDB's '$_siginfo' special variable, +# which sends a Xfer:siginfo:read query to the gdbstub. +# +# The binary causes a SIGSEGV at dereferencing a pointer with value 0xdeadbeef, +# so the test looks for and checks if this address is correctly reported by the +# gdbstub. +# +# This is launched via tests/guest-debug/run-test.py +# + +import gdb +from test_gdbstub import main, report + +def run_test(): + "Run through the test" + + gdb.execute("continue", False, True) + resp = gdb.execute("print/x $_siginfo", False, True) + report(resp.find("si_addr = 0xdeadbeef"), "Found fault address.") + +main(run_test) diff --git a/tests/tcg/multiarch/segfault.c b/tests/tcg/multiarch/segfault.c new file mode 100644 index 0000000000..e6c8ff31ca --- /dev/null +++ b/tests/tcg/multiarch/segfault.c @@ -0,0 +1,14 @@ +#include +#include + +/* Cause a segfault for testing purposes. */ + +int main(int argc, char *argv[]) +{ + int *ptr = (void *)0xdeadbeef; + + if (argc == 2 && strcmp(argv[1], "-s") == 0) { + /* Cause segfault. */ + printf("%d\n", *ptr); + } +} From 6971998e241d8edc842b165b447f706c05166ae6 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Tue, 12 Mar 2024 01:07:01 +0100 Subject: [PATCH 7/7] gdbstub: Fix double close() of the follow-fork-mode socket MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When the terminal GDB_FORK_ENABLED state is reached, the coordination socket is not needed anymore and is therefore closed. However, if there is a communication error between QEMU gdbstub and GDB, the generic error handling code attempts to close it again. Fix by closing it later - before returning - instead. Fixes: Coverity CID 1539966 Fixes: d547e711a8a5 ("gdbstub: Implement follow-fork-mode child") Signed-off-by: Ilya Leoshkevich Signed-off-by: Alex Bennée Message-Id: <20240312001813.13720-1-iii@linux.ibm.com> --- gdbstub/user.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/gdbstub/user.c b/gdbstub/user.c index 2005f3312b..edeb72efeb 100644 --- a/gdbstub/user.c +++ b/gdbstub/user.c @@ -517,6 +517,7 @@ void gdbserver_fork_end(CPUState *cpu, pid_t pid) switch (gdbserver_user_state.fork_state) { case GDB_FORK_ENABLED: if (gdbserver_user_state.running_state) { + close(fd); return; } QEMU_FALLTHROUGH; @@ -542,7 +543,6 @@ void gdbserver_fork_end(CPUState *cpu, pid_t pid) gdbserver_user_state.fork_state = GDB_FORK_ACTIVE; break; case GDB_FORK_ENABLE: - close(fd); gdbserver_user_state.fork_state = GDB_FORK_ENABLED; break; case GDB_FORK_DISABLE: @@ -557,7 +557,6 @@ void gdbserver_fork_end(CPUState *cpu, pid_t pid) if (write(fd, &b, 1) != 1) { goto fail; } - close(fd); gdbserver_user_state.fork_state = GDB_FORK_ENABLED; break; case GDB_FORK_DISABLING: