Re: [Xen-devel] [PATCH] tools/gdbsx: fix 'g' packet response for 64bit guests

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Tue, Jul 31, 2018 at 10:08:06AM +0100, Andrew Cooper wrote:
> On 31/07/18 10:00, Wei Liu wrote:
> > On Tue, Jul 31, 2018 at 04:30:42AM +0200, Marek Marczykowski-Górecki wrote:
> >> gdb 8.0 fixed bounds checking for 'g' packet (commit
> >> 9dc193c3be85aafa60ceff57d3b0430af607b4ce "Check for truncated
> >> registers in process_g_packet"). This revealed that gdbsx did
> >> not properly formatted 'g' packet - segment registers and eflags are
> >> expected to be 32-bit fields in the response (according to
> >> gdb/features/i386/64bit-core.xml in gdb sources). Specific error is:
> >>
> >>     Truncated register 26 in remote 'g' packet
> >>
> >> instead of silently truncating part of register.
> >>
> >> Additionally, it looks like segment registers of 64bit guests were never
> >> reported correctly, because of type mismatch.
> >>
> >> Signed-off-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
> >> ---
> >>  tools/debugger/gdbsx/gx/gx_local.c  |  6 +++---
> >>  tools/debugger/gdbsx/xg/xg_main.c   | 20 ++++++++++----------
> >>  tools/debugger/gdbsx/xg/xg_public.h | 18 +++++++++---------
> >>  3 files changed, 22 insertions(+), 22 deletions(-)
> >>
> >> diff --git a/tools/debugger/gdbsx/gx/gx_local.c 
> >> b/tools/debugger/gdbsx/gx/gx_local.c
> >> index 1bec03d49c..33556a582d 100644
> >> --- a/tools/debugger/gdbsx/gx/gx_local.c
> >> +++ b/tools/debugger/gdbsx/gx/gx_local.c
> >> @@ -45,8 +45,8 @@ prnt_32regs(struct xg_gdb_regs32 *r32p)
> >>  static void
> >>  prnt_64regs(struct xg_gdb_regs64 *r64p)
> >>  {
> >> -    printf("rip:"XGF64" rsp:"XGF64" flags:"XGF64"\n", r64p->rip, 
> >> r64p->rsp,
> >> -           r64p->rflags);
> >> +    printf("rip:"XGF64" rsp:"XGF64" flags:%08x\n", r64p->rip, r64p->rsp,
> >> +           r64p->eflags);
> > I think it would be better to introduce XGF32 and XGFM32 in the header.
> 
> ??? inttypes.h is a standard header for a reason...
> 
> I'd suggest instead that, if cleanup were being done, purging these
> nonstandard PRIx64's would be a much better option.
> 

This works too.

Wei.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel