accel/tcg: Always require can_do_io

Require i/o as the last insn of a TranslationBlock always,
not only with icount.  This is required for i/o that alters
the address space, such as a pci config space write.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1866
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2023-09-12 19:08:11 -07:00
parent 200c1f904f
commit 18a536f1f8
2 changed files with 7 additions and 14 deletions

View File

@ -28,12 +28,6 @@ static void set_can_do_io(DisasContextBase *db, bool val)
bool translator_io_start(DisasContextBase *db) bool translator_io_start(DisasContextBase *db)
{ {
uint32_t cflags = tb_cflags(db->tb);
if (!(cflags & CF_USE_ICOUNT)) {
return false;
}
set_can_do_io(db, true); set_can_do_io(db, true);
/* /*
@ -86,15 +80,15 @@ static TCGOp *gen_tb_start(DisasContextBase *db, uint32_t cflags)
tcg_gen_st16_i32(count, cpu_env, tcg_gen_st16_i32(count, cpu_env,
offsetof(ArchCPU, neg.icount_decr.u16.low) - offsetof(ArchCPU, neg.icount_decr.u16.low) -
offsetof(ArchCPU, env)); offsetof(ArchCPU, env));
/*
* cpu->can_do_io is set automatically here at the beginning of
* each translation block. The cost is minimal and only paid for
* -icount, plus it would be very easy to forget doing it in the
* translator.
*/
set_can_do_io(db, db->max_insns == 1 && (cflags & CF_LAST_IO));
} }
/*
* cpu->can_do_io is set automatically here at the beginning of
* each translation block. The cost is minimal, plus it would be
* very easy to forget doing it in the translator.
*/
set_can_do_io(db, db->max_insns == 1 && (cflags & CF_LAST_IO));
return icount_start_insn; return icount_start_insn;
} }

View File

@ -11212,7 +11212,6 @@ static void gen_branch(DisasContext *ctx, int insn_bytes)
/* Branches completion */ /* Branches completion */
clear_branch_hflags(ctx); clear_branch_hflags(ctx);
ctx->base.is_jmp = DISAS_NORETURN; ctx->base.is_jmp = DISAS_NORETURN;
/* FIXME: Need to clear can_do_io. */
switch (proc_hflags & MIPS_HFLAG_BMASK_BASE) { switch (proc_hflags & MIPS_HFLAG_BMASK_BASE) {
case MIPS_HFLAG_FBNSLOT: case MIPS_HFLAG_FBNSLOT:
gen_goto_tb(ctx, 0, ctx->base.pc_next + insn_bytes); gen_goto_tb(ctx, 0, ctx->base.pc_next + insn_bytes);