From 2627e4524ea6c6ba14f9d6b298e08c9d4d3cc4fe Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 6 Feb 2023 09:26:29 -1000 Subject: [PATCH] accel/tcg: Allow the second page of an instruction to be MMIO MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit If an instruction straddles a page boundary, and the first page was ram, but the second page was MMIO, we would abort. Handle this as if both pages are MMIO, by setting the ram_addr_t for the first page to -1. Reported-by: Sid Manning Reported-by: Jørgen Hansen Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson --- accel/tcg/translator.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c index ef5193c67e..1cf404ced0 100644 --- a/accel/tcg/translator.c +++ b/accel/tcg/translator.c @@ -176,8 +176,16 @@ static void *translator_access(CPUArchState *env, DisasContextBase *db, if (host == NULL) { tb_page_addr_t phys_page = get_page_addr_code_hostp(env, base, &db->host_addr[1]); - /* We cannot handle MMIO as second page. */ - assert(phys_page != -1); + + /* + * If the second page is MMIO, treat as if the first page + * was MMIO as well, so that we do not cache the TB. + */ + if (unlikely(phys_page == -1)) { + tb_set_page_addr0(tb, -1); + return NULL; + } + tb_set_page_addr1(tb, phys_page); #ifdef CONFIG_USER_ONLY page_protect(end); -- 2.11.0