From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56025) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e1uW7-0003BH-Il for qemu-devel@nongnu.org; Tue, 10 Oct 2017 09:24:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e1uW1-0004Y7-JZ for qemu-devel@nongnu.org; Tue, 10 Oct 2017 09:24:15 -0400 Received: from mail-wm0-f41.google.com ([74.125.82.41]:47460) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1e1uW1-0004VF-Co for qemu-devel@nongnu.org; Tue, 10 Oct 2017 09:24:09 -0400 Received: by mail-wm0-f41.google.com with SMTP id t69so5157461wmt.2 for ; Tue, 10 Oct 2017 06:24:06 -0700 (PDT) References: <1506524313-20037-1-git-send-email-thuth@redhat.com> From: Paolo Bonzini Message-ID: <59cd0315-bc0e-87dd-7738-35242a7c9676@redhat.com> Date: Tue, 10 Oct 2017 15:24:03 +0200 MIME-Version: 1.0 In-Reply-To: <1506524313-20037-1-git-send-email-thuth@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] disas: Always initialize read_memory_inner_func properly List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Huth , qemu-devel@nongnu.org Cc: Julian Brown , Peter Maydell , qemu-arm@nongnu.org, Richard Henderson On 27/09/2017 16:58, Thomas Huth wrote: > I've recently seen this with valgrind while running the HMP tester: > > ==22373== Conditional jump or move depends on uninitialised value(s) > ==22373== at 0x4A41FD: arm_disas_set_info (cpu.c:504) > ==22373== by 0x3867A7: monitor_disas (disas.c:390) > ==22373== by 0x38E80E: memory_dump (monitor.c:1339) > ==22373== by 0x38FA43: handle_hmp_command (monitor.c:3123) > ==22373== by 0x38FB9E: qmp_human_monitor_command (monitor.c:613) > ==22373== by 0x4E3124: qmp_marshal_human_monitor_command (qmp-marshal.c:1736) > ==22373== by 0x769678: do_qmp_dispatch (qmp-dispatch.c:104) > ==22373== by 0x769678: qmp_dispatch (qmp-dispatch.c:131) > ==22373== by 0x38B734: handle_qmp_command (monitor.c:3853) > ==22373== by 0x76ED07: json_message_process_token (json-streamer.c:105) > ==22373== by 0x78D40A: json_lexer_feed_char (json-lexer.c:323) > ==22373== by 0x78D4CD: json_lexer_feed (json-lexer.c:373) > ==22373== by 0x38A08D: monitor_qmp_read (monitor.c:3895) > > And indeed, in monitor_disas, the read_memory_inner_func variable was > not initialized, but arm_disas_set_info() expects this to be NULL > or a valid pointer. Let's properly set this to NULL in the > INIT_DISASSEMBLE_INFO to fix it in all functions that use the > disassemble_info struct. > > Fixes: f7478a92dd9ee2276bfaa5b7317140d3f9d6a53b ("Fix Thumb-1 BE32 execution") > Signed-off-by: Thomas Huth > --- > disas.c | 1 - > include/disas/bfd.h | 1 + > 2 files changed, 1 insertion(+), 1 deletion(-) > > diff --git a/disas.c b/disas.c > index d6a1eb9..54eea3f 100644 > --- a/disas.c > +++ b/disas.c > @@ -190,7 +190,6 @@ void target_disas(FILE *out, CPUState *cpu, target_ulong code, > > s.cpu = cpu; > s.info.read_memory_func = target_read_memory; > - s.info.read_memory_inner_func = NULL; > s.info.buffer_vma = code; > s.info.buffer_length = size; > s.info.print_address_func = generic_print_address; > diff --git a/include/disas/bfd.h b/include/disas/bfd.h > index b01e002..d99da68 100644 > --- a/include/disas/bfd.h > +++ b/include/disas/bfd.h > @@ -479,6 +479,7 @@ int generic_symbol_at_address(bfd_vma, struct disassemble_info *); > (INFO).buffer_vma = 0, \ > (INFO).buffer_length = 0, \ > (INFO).read_memory_func = buffer_read_memory, \ > + (INFO).read_memory_inner_func = NULL, \ > (INFO).memory_error_func = perror_memory, \ > (INFO).print_address_func = generic_print_address, \ > (INFO).print_insn = NULL, \ > Queued, thanks. Paolo