| Message ID | 1d5b26fed5e9648e4672545085509ea5ad8a9a60.1460625412.git.atar4qemu@gmail.com |
|---|---|
| State | New |
| Headers | show |
On 14/04/16 10:29, Artyom Tarasenko wrote: > Accoding the chapter 7.6 Trap Processing of the SPARC Architecture Manual v9, > the Trap Based Address Register is not modified as a trap is taken. > > This fix allows booting FreeBSD-10.3-RELEASE-sparc64. > > Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com> > --- > target-sparc/int64_helper.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/target-sparc/int64_helper.c b/target-sparc/int64_helper.c > index aa876cd..29360fa 100644 > --- a/target-sparc/int64_helper.c > +++ b/target-sparc/int64_helper.c > @@ -158,9 +158,8 @@ void sparc_cpu_do_interrupt(CPUState *cs) > } else if ((intno & 0x1c0) == TT_FILL) { > cpu_set_cwp(env, cpu_cwp_inc(env, env->cwp + 1)); > } > - env->tbr &= ~0x7fffULL; > - env->tbr |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); > - env->pc = env->tbr; > + env->pc = env->tbr & ~0x7fffULL; > + env->pc |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); > env->npc = env->pc + 4; > cs->exception_index = -1; > } > Gosh yes, this is entirely obvious when you consider that taking a trap shouldn't actually alter the register containing the address of the trap table in memory :( Again the patch applies with fuzz and checkpatch.pl complains about line-endings but if you can rebase/resend then you can add my Reviewed-by. Given that such a trivial fix unlocks FreeBSD then I'm okay with this in 2.6 too. ATB, Mark.
On Thu, Apr 14, 2016 at 3:43 PM, Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> wrote: > On 14/04/16 10:29, Artyom Tarasenko wrote: > >> Accoding the chapter 7.6 Trap Processing of the SPARC Architecture Manual v9, >> the Trap Based Address Register is not modified as a trap is taken. >> >> This fix allows booting FreeBSD-10.3-RELEASE-sparc64. >> >> Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com> >> --- >> target-sparc/int64_helper.c | 5 ++--- >> 1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/target-sparc/int64_helper.c b/target-sparc/int64_helper.c >> index aa876cd..29360fa 100644 >> --- a/target-sparc/int64_helper.c >> +++ b/target-sparc/int64_helper.c >> @@ -158,9 +158,8 @@ void sparc_cpu_do_interrupt(CPUState *cs) >> } else if ((intno & 0x1c0) == TT_FILL) { >> cpu_set_cwp(env, cpu_cwp_inc(env, env->cwp + 1)); >> } >> - env->tbr &= ~0x7fffULL; >> - env->tbr |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); >> - env->pc = env->tbr; >> + env->pc = env->tbr & ~0x7fffULL; >> + env->pc |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); >> env->npc = env->pc + 4; >> cs->exception_index = -1; >> } >> > > Gosh yes, this is entirely obvious when you consider that taking a trap > shouldn't actually alter the register containing the address of the trap > table in memory :( Well, it does alter it in SPARCv8, I guess that's where the bug is coming from. > > Again the patch applies with fuzz and checkpatch.pl complains about > line-endings but if you can rebase/resend then you can add my This is strange. I've rebased it today on 8b4aaba736e55c8ab6d71350f850a6642f0165b9, and $ scripts/checkpatch.pl 0002-target-sparc-fix-Trap-Based-Address-Register-behavio.patch total: 0 errors, 0 warnings, 11 lines checked 0002-target-sparc-fix-Trap-Based-Address-Register-behavio.patch has no obvious style problems and is ready for Submission. Artyom > Reviewed-by. Given that such a trivial fix unlocks FreeBSD then I'm okay > with this in 2.6 too. > > > ATB, > > Mark. >
diff --git a/target-sparc/int64_helper.c b/target-sparc/int64_helper.c index aa876cd..29360fa 100644 --- a/target-sparc/int64_helper.c +++ b/target-sparc/int64_helper.c @@ -158,9 +158,8 @@ void sparc_cpu_do_interrupt(CPUState *cs) } else if ((intno & 0x1c0) == TT_FILL) { cpu_set_cwp(env, cpu_cwp_inc(env, env->cwp + 1)); } - env->tbr &= ~0x7fffULL; - env->tbr |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); - env->pc = env->tbr; + env->pc = env->tbr & ~0x7fffULL; + env->pc |= ((env->tl > 1) ? 1 << 14 : 0) | (intno << 5); env->npc = env->pc + 4; cs->exception_index = -1; }
Accoding the chapter 7.6 Trap Processing of the SPARC Architecture Manual v9, the Trap Based Address Register is not modified as a trap is taken. This fix allows booting FreeBSD-10.3-RELEASE-sparc64. Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com> --- target-sparc/int64_helper.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)