From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Date: Sat, 03 Aug 2002 03:29:02 +0000 Subject: [Linux-ia64] Re: CPU hotplug boot change for IA64 Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org In message <20020802134915.ED77.K-SUGANUMA@mvj.biglobe.ne.jp> you write: > Bit for CPU#0 on cpu_online_map was set at smp_boot_cpus() before. > But on the 2.5.29, place of calling smp_boot_cpus() is changed to > later timing and this seems to make a chance that smp_call_function() > is called before setting cpu_online_map, (I guess.) > In that case, smp_call_function won't return because num_online_cpus() > returns 0 and the system will hang. > > I have an experience of this problem only on a large system > like Tiger, but it may occur on another system. > > Rusty, I guess this modification should be needed for i386, too. You should *not* be calling smp_call_function before smp_prepare_cpus. I know kgdb can do this, but it's a special case. Rusty. -- Anyone who quotes me in their sig is an idiot. -- Rusty Russell.