From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH RFC] fix sun6i crash on setup_pagetables Date: Thu, 25 Jul 2013 15:23:10 +0100 Message-ID: <51F134CE.4060102@linaro.org> References: <1374668066-4413-1-git-send-email-bjzhang@suse.com> <51F01DED.4020703@linaro.org> <1374722942.32286.32.camel@hastur.hellion.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1374722942.32286.32.camel@hastur.hellion.org.uk> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: xen-devel@lists.xen.org, Stefano Stabellini , Bamvor Jian Zhang List-Id: xen-devel@lists.xenproject.org On 07/25/2013 04:29 AM, Ian Campbell wrote: > On Wed, 2013-07-24 at 19:33 +0100, Julien Grall wrote: >> On 07/24/2013 01:14 PM, Bamvor Jian Zhang wrote: >>> this patch move set_processor_id in front of setup_pagetables >>> in order to fix crash when calling this_cpu in that functions. >>> the HPTIDR is unknown value according to ARM ARM 7AR(DDI0406C), >>> B4-1598. we should use it before using it. >>> >>> but i do not know why other board like arndale board. should >>> bootloader write this register? >> >> On the Arndale, by default the value of HPTIDR is equal to 0. So it >> works without any issue. > > Right, but strictly the register is undefined reset on reset. > > The bootloader cannot initialise it because the meaning is entirely OS > specific. > >> During the afternoon, I have noticed this error and send a similar >> patch few minutes ago. I also moved percpu_init_areas earlier. > > Right, I think this makes sense. > > I suppose I should just take your (Julien's) version of this patch? If you take my patch, could you slighty modify the commit message to specify that's in an issue on sun6i? >> For the next patches, could you add the appropriate people? It will >> avoid to loose your patch with the other mail of the mailing list :). > > Yes please! > >> >>> >>> Signed-off-by: Bamvor Jian Zhang >>> --- >>> xen/arch/arm/setup.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c >>> index 2f9fdc8..3bf1b40 100644 >>> --- a/xen/arch/arm/setup.c >>> +++ b/xen/arch/arm/setup.c >>> @@ -437,6 +437,7 @@ void __init start_xen(unsigned long boot_phys_offset, >>> cpus = smp_get_max_cpus(); >>> cmdline_parse(device_tree_bootargs(device_tree_flattened)); >>> >>> + set_processor_id(0); /* needed early, for this_cpu() */ >>> setup_pagetables(boot_phys_offset, get_xen_paddr()); >>> setup_mm(fdt_paddr, fdt_size); >>> >>> @@ -459,7 +460,6 @@ void __init start_xen(unsigned long boot_phys_offset, >>> make_cpus_ready(cpus, boot_phys_offset); >>> >>> percpu_init_areas(); >> >> I think you can also move percpu_init_areas earlier. >> >>> - set_processor_id(0); /* needed early, for smp_processor_id() */ >>> set_current((struct vcpu *)0xfffff000); /* debug sanity */ >>> idle_vcpu[0] = current; >>> >>> >> > >