i386-tdep: Verify architecture before proceeding with `set/show mpx'
Commit Message
Make sure the architecture is `bfd_arch_i386' before handling the `set
mpx' and `show mpx' commands, avoiding the issue with `i386_mpx_enabled'
interpreting `gdbarch->tdep' according to the `struct gdbarch_tdep'
definition in i386-tdep.h while indeed in a multi-target configuration
it may have a different layout and cause GDB to crash or at least
misbehave.
gdb/
* i386-tdep.c (i386_mpx_info_bounds): Make sure the architecture
is `bfd_arch_i386' before proceeding.
(i386_mpx_set_bounds): Likewise.
---
Hi,
Noticed in `mips-mti-linux-gnu' `--enable-targets=all' regression testing
with an upcoming change which modifies the mips-tdep.h definition of
`struct gdbarch_tdep', showing up as:
(gdb) PASS: gdb.base/default.exp: info stack
info set
ada print-signatures: Whether the output of formal and return types for functions in the overloads selection menu is activated is on.
[...]
mipsfpu: The MIPS floating-point coprocessor is set automatically (currently double-precision)
ERROR: Process no longer exists
UNRESOLVED: gdb.base/default.exp: info set
which is a segfault due to the retrieved numerical value of `tdep->tdesc'
being 4 in `i386_mpx_enabled'. With the change in place, the test case
now passes, with the expected message produced:
(gdb) PASS: gdb.base/default.exp: info stack
info set
ada print-signatures: Whether the output of formal and return types for functions in the overloads selection menu is activated is on.
[...]
mipsfpu: The MIPS floating-point coprocessor is set automatically (currently double-precision)
mpx bound: Intel Memory Protection Extensions not supported on this target.
multiple-symbols: How the debugger handles ambiguities in expressions is "all".
[...]
write: Writing into executable and core files is off.
(gdb) PASS: gdb.base/default.exp: info set
I've decided to quit from `i386_mpx_info_bounds' and `i386_mpx_set_bounds'
right away for code clarity rather than burying the condition within
`i386_mpx_enabled'.
OK to apply?
Maciej
gdb-i386-mpx-arch.diff
Comments
On 10/17/2016 04:15 PM, Maciej W. Rozycki wrote:
> I've decided to quit from `i386_mpx_info_bounds' and `i386_mpx_set_bounds'
> right away for code clarity rather than burying the condition within
> `i386_mpx_enabled'.
>
> OK to apply?
OK.
Thanks,
Pedro Alves
On Mon, 17 Oct 2016, Pedro Alves wrote:
> OK.
Committed, thanks.
Maciej
===================================================================
@@ -8857,7 +8857,8 @@ i386_mpx_info_bounds (char *args, int fr
struct gdbarch *gdbarch = get_current_arch ();
struct type *data_ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
- if (!i386_mpx_enabled ())
+ if (gdbarch_bfd_arch_info (gdbarch)->arch != bfd_arch_i386
+ || !i386_mpx_enabled ())
{
printf_unfiltered (_("Intel Memory Protection Extensions not "
"supported on this target.\n"));
@@ -8900,7 +8901,8 @@ i386_mpx_set_bounds (char *args, int fro
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
struct type *data_ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
- if (!i386_mpx_enabled ())
+ if (gdbarch_bfd_arch_info (gdbarch)->arch != bfd_arch_i386
+ || !i386_mpx_enabled ())
error (_("Intel Memory Protection Extensions not supported\
on this target."));