| Message ID | 7b3b6f6a47306f204437e46005ed2098545e6c80.1478291230.git.atar4qemu@gmail.com |
|---|---|
| State | New |
| Headers | show |
On 11/04/2016 02:50 PM, Artyom Tarasenko wrote: > + if (is_exec) { /* XXX has_hypervisor */ > + if (env->lsu & (IMMU_E)) { > + cpu_raise_exception_ra(env, TT_CODE_ACCESS, GETPC()); > + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) { > + cpu_raise_exception_ra(env, TT_INSN_REAL_TRANSLATION_MISS, GETPC()); > + } > + } else { > + if (env->lsu & (DMMU_E)) { > + cpu_raise_exception_ra(env, TT_DATA_ACCESS, GETPC()); > + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) { > + cpu_raise_exception_ra(env, TT_DATA_REAL_TRANSLATION_MISS, GETPC()); > + } > + } And if the hypervisor itself has a bug and references bad memory? Or does the hypervisor *have* to do such things in order to probe for device on startup, and should therefore not trap. I'm actually assuming this is the case based on the fact that you wrote this patch in the first place. But if so, we need a comment here. r~
On Fri, Nov 4, 2016 at 10:19 PM, Richard Henderson <rth@twiddle.net> wrote: > On 11/04/2016 02:50 PM, Artyom Tarasenko wrote: >> >> + if (is_exec) { /* XXX has_hypervisor */ >> + if (env->lsu & (IMMU_E)) { >> + cpu_raise_exception_ra(env, TT_CODE_ACCESS, GETPC()); >> + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) >> { >> + cpu_raise_exception_ra(env, TT_INSN_REAL_TRANSLATION_MISS, >> GETPC()); >> + } >> + } else { >> + if (env->lsu & (DMMU_E)) { >> + cpu_raise_exception_ra(env, TT_DATA_ACCESS, GETPC()); >> + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) >> { >> + cpu_raise_exception_ra(env, TT_DATA_REAL_TRANSLATION_MISS, >> GETPC()); >> + } >> + } > > > And if the hypervisor itself has a bug and references bad memory? The MMU is usually switched on. The exception is the early initialization. > Or does > the hypervisor *have* to do such things in order to probe for device on > startup, and should therefore not trap. > > I'm actually assuming this is the case based on the fact that you wrote this > patch in the first place. Yep. > But if so, we need a comment here. With MMU switched off there is no circuit which would produce a MMU fault. Neither under sun4v nor under sun4u. Do we really have to document it? Btw it works the same way under sun4m just 26 lines above.
diff --git a/target-sparc/cpu.h b/target-sparc/cpu.h index 5fb0ed1..e0b2806 100644 --- a/target-sparc/cpu.h +++ b/target-sparc/cpu.h @@ -68,6 +68,8 @@ #define TT_DATA_ACCESS 0x32 #define TT_UNALIGNED 0x34 #define TT_PRIV_ACT 0x37 +#define TT_INSN_REAL_TRANSLATION_MISS 0x3e +#define TT_DATA_REAL_TRANSLATION_MISS 0x3f #define TT_EXTINT 0x40 #define TT_IVEC 0x60 #define TT_TMISS 0x64 diff --git a/target-sparc/ldst_helper.c b/target-sparc/ldst_helper.c index de7d53a..fdca87f 100644 --- a/target-sparc/ldst_helper.c +++ b/target-sparc/ldst_helper.c @@ -1664,14 +1664,25 @@ void sparc_cpu_unassigned_access(CPUState *cs, hwaddr addr, { SPARCCPU *cpu = SPARC_CPU(cs); CPUSPARCState *env = &cpu->env; - int tt = is_exec ? TT_CODE_ACCESS : TT_DATA_ACCESS; #ifdef DEBUG_UNASSIGNED printf("Unassigned mem access to " TARGET_FMT_plx " from " TARGET_FMT_lx "\n", addr, env->pc); #endif - cpu_raise_exception_ra(env, tt, GETPC()); + if (is_exec) { /* XXX has_hypervisor */ + if (env->lsu & (IMMU_E)) { + cpu_raise_exception_ra(env, TT_CODE_ACCESS, GETPC()); + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) { + cpu_raise_exception_ra(env, TT_INSN_REAL_TRANSLATION_MISS, GETPC()); + } + } else { + if (env->lsu & (DMMU_E)) { + cpu_raise_exception_ra(env, TT_DATA_ACCESS, GETPC()); + } else if (cpu_has_hypervisor(env) && !(env->hpstate & HS_PRIV)) { + cpu_raise_exception_ra(env, TT_DATA_REAL_TRANSLATION_MISS, GETPC()); + } + } } #endif #endif
while IMMU/DMMU is disabled - ignore MMU-faults in hypervisorv mode or if CPU doesn't have hypervisor - signal TT_INSN_REAL_TRANSLATION_MISS/TT_DATA_REAL_TRANSLATION_MISS otherwise Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com> --- target-sparc/cpu.h | 2 ++ target-sparc/ldst_helper.c | 15 +++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-)