Re: [Qemu-devel] [PATCH] Register only one qbus_reset_all_fn() for system bus

[Isaku Yamahata <yamahata@valinux.co.jp>]

> Have you verified that all bus devices have been qdevified since this
> code has been added? I wouldn't bet it is the case.

I think his analysis is valid. So how about the following patch.

>From ee27041a238d51247e30100d1909066978cd8858 Mon Sep 17 00:00:00 2001
Message-Id: <ee27041a238d51247e30100d1909066978cd8858.1301703026.git.yamahata@valinux.co.jp>
From: Isaku Yamahata <yamahata@valinux.co.jp>
Date: Sat, 2 Apr 2011 09:04:54 +0900
Subject: [PATCH] qdev: Register only one qbus_reset_all_fn() for system bus

This is the revised version of Dmitry's.
his report is as follows and this patch fixes it.
> Currently reset handler is registered for System bus twice: once during
> bus creation and once in vl.c. Remove the second qemu_register_reset()
> invocation. Also while we are at it, remove incorrect check at
> qbus_create_inplace(): when system bus is created, main_system_bus is
> NULL (as it's not yet created, it cannot be set), so the check is just
> wrong.

the check bus == main_system_bus in qbus_create_inplace() was wrong
because sysbus_get_default() creates bus for main_system_bus and then
set main_system_bus to it.
So main_system_bus == NULL in qbus_create_inplace() when creating
main_system_bus. So this patch fixes the check whether creating
main_system_bus or not by seeing BusInfo.

Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
---
 hw/qdev.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/hw/qdev.c b/hw/qdev.c
index 1aa1ea0..659de23 100644
--- a/hw/qdev.c
+++ b/hw/qdev.c
@@ -762,7 +762,12 @@ void qbus_create_inplace(BusState *bus, BusInfo *info,
     if (parent) {
         QLIST_INSERT_HEAD(&parent->child_bus, bus, sibling);
         parent->num_child_bus++;
-    } else if (bus != main_system_bus) {
+    } else if (info != &system_bus_info) {
+        /* see if bus == main_system_bus
+         * Here we can't check bus == main_system_bus because
+         * main_system_bus == NULL here before setting it by
+         * sysbus_get_default()
+         */
         /* TODO: once all bus devices are qdevified,
            only reset handler for main_system_bus should be registered here. */
         qemu_register_reset(qbus_reset_all_fn, bus);
-- 
1.7.1.1



-- 
yamahata