Re: [PATCH v4 0/5] Powerpc/Watchpoint: Few important fixes

[Ravi Bangoria]

On 10/12/19 2:21 PM, Christophe Leroy wrote:
> Le 10/10/2019 Ã 06:44, Ravi Bangoria a ÃcritÂ:
> > > > @Christophe, Is patch5 works for you on 8xx?
> > >
> > > Getting the following :
> > >
> > > root@vgoip:~# ./ptrace-hwbreak
> > > test: ptrace-hwbreak
> > > tags: git_version:v5.4-rc2-710-gf0082e173fe4-dirty
> > > PTRACE_SET_DEBUGREG, WO, len: 1: Ok
> > > PTRACE_SET_DEBUGREG, WO, len: 2: Ok
> > > PTRACE_SET_DEBUGREG, WO, len: 4: Ok
> > > PTRACE_SET_DEBUGREG, WO, len: 8: Ok
> > > PTRACE_SET_DEBUGREG, RO, len: 1: Ok
> > > PTRACE_SET_DEBUGREG, RO, len: 2: Ok
> > > PTRACE_SET_DEBUGREG, RO, len: 4: Ok
> > > PTRACE_SET_DEBUGREG, RO, len: 8: Ok
> > > PTRACE_SET_DEBUGREG, RW, len: 1: Ok
> > > PTRACE_SET_DEBUGREG, RW, len: 2: Ok
> > > PTRACE_SET_DEBUGREG, RW, len: 4: Ok
> > > PTRACE_SET_DEBUGREG, RW, len: 8: Ok
> > > PPC_PTRACE_SETHWDEBUG, MODE_EXACT, WO, len: 1: Ok
> > > PPC_PTRACE_SETHWDEBUG, MODE_EXACT, RO, len: 1: Ok
> > > PPC_PTRACE_SETHWDEBUG, MODE_EXACT, RW, len: 1: Ok
> > > PPC_PTRACE_SETHWDEBUG, MODE_RANGE, DW ALIGNED, WO, len: 6: Ok
> > > PPC_PTRACE_SETHWDEBUG, MODE_RANGE, DW ALIGNED, RO, len: 6: Fail
> > > failure: ptrace-hwbreak
>
> I also tried on a 83xx (book3s/32). This one has a regular DABR :
>
> root@vgoippro:~# ./ptrace-hwbreak
> test: ptrace-hwbreak
> tags: git_version:v5.4-rc2-710-gf0082e173fe4-dirty
> PTRACE_SET_DEBUGREG, WO, len: 1: Ok
> PTRACE_SET_DEBUGREG, WO, len: 2: Ok
> PTRACE_SET_DEBUGREG, WO, len: 4: Ok
> PTRACE_SET_DEBUGREG, WO, len: 8: Ok
> PTRACE_SET_DEBUGREG, RO, len: 1: Ok
> PTRACE_SET_DEBUGREG, RO, len: 2: Ok
> PTRACE_SET_DEBUGREG, RO, len: 4: Ok
> PTRACE_SET_DEBUGREG, RO, len: 8: Ok
> PTRACE_SET_DEBUGREG, RW, len: 1: Ok
> PTRACE_SET_DEBUGREG, RW, len: 2: Ok
> PTRACE_SET_DEBUGREG, RW, len: 4: Ok
> PTRACE_SET_DEBUGREG, RW, len: 8: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_EXACT, WO, len: 1: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_EXACT, RO, len: 1: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_EXACT, RW, len: 1: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_RANGE, DW ALIGNED, WO, len: 6: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_RANGE, DW ALIGNED, RO, len: 6: Ok
> PPC_PTRACE_SETHWDEBUG, MODE_RANGE, DW ALIGNED, RW, len: 6: Ok
> PPC_PTRACE_SETHWDEBUG failed: Invalid argument

Ok. If it has the DABR _only_, creation of MODE RANGE UNALINGED breakpoint
will failed because DABR supports only 8 bytes wide breakpoint and it must
be doubleword aligned.

So this means I've to add all unaligned tests inside if (dawr) condition.

Ravi