On Wed, 2015-04-08 at 19:50 +0200, Ulrich Weigand wrote: > Anshuman Khandual <khand...@linux.vnet.ibm.com> wrote on 23.03.2015 > 11:34:30: > > > > With that in mind, do we have a way to set the top 32bits of the MSR > > > (which contain the TM bits) when ptracing 32 bit processes? I can't > > > find anything like that in this patch set. > > > > No, we dont have that yet. When ptracing in 32-bit mode the MSR value > > which can be viewed or set from the user space through PTRACE_GETREGS > > PTRACE_SETREGS call is it's lower 32 bits only. Either we can club > > the upper 32 bits of MSR as part of one of the ELF core notes we are > > adding in the patch series or we can create one more separate ELF core > > note for that purpose. Let me know your opinion on this. > > I'm not sure I understand this. I thought we had the following: > > - If the process calling ptrace is itself 64-bit (which is how GDB is > built on all current Linux distributions), then PTRACE_GETREGS etc. > will *always* operate on 64-bit register sets, even if the target > process is 32-bit. > > - If the process calling ptrace is 32-bit, then PTRACE_GETREGS will > operate on 32-bit register sets. However, there is a separate > PTRACE_GETREGS64 / PTRACE_SETREGS64 call that will also provide > the opportunity to operate on the full 64-bit register set. Both > apply independently of whether the target process is 32-bit or > 64-bit. > > Is this not correct?
I think you're correct. We should be right. I'd forgotten about the GET/SETREGS64 interfaces. Mikey _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev