| Message ID | 20240604071833.962574-12-pbonzini@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/i386: fixes for INHIBIT_IRQ, TF and RF | expand |
On 6/4/24 02:18, Paolo Bonzini wrote: > DISAS_NORETURN suppresses the work normally done by gen_eob(), and therefore > must be used in special cases only. Document them. > > Signed-off-by: Paolo Bonzini<pbonzini@redhat.com> > --- > target/i386/tcg/translate.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/target/i386/tcg/translate.c b/target/i386/tcg/translate.c index a9c6424c7df..2b6f67be40b 100644 --- a/target/i386/tcg/translate.c +++ b/target/i386/tcg/translate.c @@ -4761,6 +4761,17 @@ static void i386_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu) switch (dc->base.is_jmp) { case DISAS_NORETURN: + /* + * Most instructions should not use DISAS_NORETURN, as that suppresses + * the handling of hflags normally done by gen_eob(). We can + * get here: + * - for exception and interrupts + * - for jump optimization (which is disabled by INHIBIT_IRQ/RF/TF) + * - for VMRUN because RF/TF handling for the host is done after vmexit, + * and INHIBIT_IRQ is loaded from the VMCB + * - for HLT/PAUSE/MWAIT to exit the main loop with specific EXCP_* values; + * the helpers handle themselves the tasks normally done by gen_eob(). + */ break; case DISAS_TOO_MANY: gen_update_cc_op(dc);
DISAS_NORETURN suppresses the work normally done by gen_eob(), and therefore must be used in special cases only. Document them. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- target/i386/tcg/translate.c | 11 +++++++++++ 1 file changed, 11 insertions(+)