| Message ID | 20240801202340.21845-1-iii@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | linux-user/elfload: Fix pr_pid values in core files | expand |
On 8/2/24 06:23, Ilya Leoshkevich wrote: > Analyzing qemu-produced core dumps of multi-threaded apps runs into: > > (gdb) info threads > [...] > 21 Thread 0x3ff83cc0740 (LWP 9295) warning: Couldn't find general-purpose registers in core file. > <unavailable> in ?? () > > The reason is that all pr_pid values are the same, because the same > TaskState is used for all CPUs when generating NT_PRSTATUS notes. > > Fix by using TaskStates associated with individual CPUs. > > Cc:qemu-stable@nongnu.org > Fixes: 243c47066253 ("linux-user/elfload: Write corefile elf header in one block") > Signed-off-by: Ilya Leoshkevich<iii@linux.ibm.com> > --- > linux-user/elfload.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) Oops, Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
On 1/8/24 22:23, Ilya Leoshkevich wrote: > Analyzing qemu-produced core dumps of multi-threaded apps runs into: > > (gdb) info threads > [...] > 21 Thread 0x3ff83cc0740 (LWP 9295) warning: Couldn't find general-purpose registers in core file. > <unavailable> in ?? () > > The reason is that all pr_pid values are the same, because the same > TaskState is used for all CPUs when generating NT_PRSTATUS notes. > > Fix by using TaskStates associated with individual CPUs. > > Cc: qemu-stable@nongnu.org > Fixes: 243c47066253 ("linux-user/elfload: Write corefile elf header in one block") Isn't it Fixes: edf8e2af14 ("linux-user: implemented ELF coredump") ? > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > --- > linux-user/elfload.c | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
On Fri, 2024-08-02 at 15:20 +0200, Philippe Mathieu-Daudé wrote: > On 1/8/24 22:23, Ilya Leoshkevich wrote: > > Analyzing qemu-produced core dumps of multi-threaded apps runs > > into: > > > > (gdb) info threads > > [...] > > 21 Thread 0x3ff83cc0740 (LWP 9295) warning: Couldn't find > > general-purpose registers in core file. > > <unavailable> in ?? () > > > > The reason is that all pr_pid values are the same, because the same > > TaskState is used for all CPUs when generating NT_PRSTATUS notes. > > > > Fix by using TaskStates associated with individual CPUs. > > > > Cc: qemu-stable@nongnu.org > > Fixes: 243c47066253 ("linux-user/elfload: Write corefile elf header > > in one block") > > Isn't it > > Fixes: edf8e2af14 ("linux-user: implemented ELF coredump") > > ? I haven't tested it, but this looks correct: static void fill_thread_info(struct elf_note_info *info, const CPUState *env) { TaskState *ts = (TaskState *)env->opaque; > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > > --- > > linux-user/elfload.c | 8 +++----- > > 1 file changed, 3 insertions(+), 5 deletions(-) > > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> >
diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 7ecbc8a7cc0..0861f115fc4 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -4102,8 +4102,7 @@ static void fill_elf_note_phdr(struct elf_phdr *phdr, size_t sz, off_t offset) bswap_phdr(phdr, 1); } -static void fill_prstatus_note(void *data, const TaskState *ts, - CPUState *cpu, int signr) +static void fill_prstatus_note(void *data, CPUState *cpu, int signr) { /* * Because note memory is only aligned to 4, and target_elf_prstatus @@ -4113,7 +4112,7 @@ static void fill_prstatus_note(void *data, const TaskState *ts, struct target_elf_prstatus prstatus = { .pr_info.si_signo = signr, .pr_cursig = signr, - .pr_pid = ts->ts_tid, + .pr_pid = get_task_state(cpu)->ts_tid, .pr_ppid = getppid(), .pr_pgrp = getpgrp(), .pr_sid = getsid(0), @@ -4428,8 +4427,7 @@ static int elf_core_dump(int signr, const CPUArchState *env) CPU_FOREACH(cpu_iter) { dptr = fill_note(&hptr, NT_PRSTATUS, "CORE", sizeof(struct target_elf_prstatus)); - fill_prstatus_note(dptr, ts, cpu_iter, - cpu_iter == cpu ? signr : 0); + fill_prstatus_note(dptr, cpu_iter, cpu_iter == cpu ? signr : 0); } if (dump_write(fd, header, data_offset) < 0) {
Analyzing qemu-produced core dumps of multi-threaded apps runs into: (gdb) info threads [...] 21 Thread 0x3ff83cc0740 (LWP 9295) warning: Couldn't find general-purpose registers in core file. <unavailable> in ?? () The reason is that all pr_pid values are the same, because the same TaskState is used for all CPUs when generating NT_PRSTATUS notes. Fix by using TaskStates associated with individual CPUs. Cc: qemu-stable@nongnu.org Fixes: 243c47066253 ("linux-user/elfload: Write corefile elf header in one block") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- linux-user/elfload.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)