* [PATCH] Fix NULL pointer for Xen guests
@ 2010-04-27 15:24 Prarit Bhargava
2010-04-27 16:58 ` [LKML] " Konrad Rzeszutek Wilk
` (3 more replies)
0 siblings, 4 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-04-27 15:24 UTC (permalink / raw)
To: linux-kernel, suresh.b.siddha, x86, clalance, drjones; +Cc: Prarit Bhargava
Upstream PV guests fail to boot because of a NULL pointer. It is possible that
xen guests have irq_desc->chip_data = NULL.
Test for NULL chip_data pointer before attempting to complete an irq move.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 127b871..eb2789c 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
struct irq_desc *desc = irq_to_desc(irq);
struct irq_cfg *cfg = desc->chip_data;
+ if (!cfg)
+ return;
+
__irq_complete_move(&desc, cfg->vector);
}
#else
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 15:24 [PATCH] Fix NULL pointer for Xen guests Prarit Bhargava
@ 2010-04-27 16:58 ` Konrad Rzeszutek Wilk
2010-04-27 17:09 ` Prarit Bhargava
2010-04-28 18:26 ` Andrew Morton
` (2 subsequent siblings)
3 siblings, 1 reply; 20+ messages in thread
From: Konrad Rzeszutek Wilk @ 2010-04-27 16:58 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On Tue, Apr 27, 2010 at 11:24:42AM -0400, Prarit Bhargava wrote:
> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
> xen guests have irq_desc->chip_data = NULL.
Can you provide a short example of test scenario? As in what I should do
to reproduce this problem?
>
> Test for NULL chip_data pointer before attempting to complete an irq move.
>
> Signed-off-by: Prarit Bhargava <prarit@redhat.com>
> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
>
> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> index 127b871..eb2789c 100644
> --- a/arch/x86/kernel/apic/io_apic.c
> +++ b/arch/x86/kernel/apic/io_apic.c
> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> struct irq_desc *desc = irq_to_desc(irq);
> struct irq_cfg *cfg = desc->chip_data;
>
> + if (!cfg)
> + return;
> +
> __irq_complete_move(&desc, cfg->vector);
> }
> #else
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 16:58 ` [LKML] " Konrad Rzeszutek Wilk
@ 2010-04-27 17:09 ` Prarit Bhargava
2010-04-27 17:59 ` Andrew Jones
2010-04-27 18:34 ` Konrad Rzeszutek Wilk
0 siblings, 2 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-04-27 17:09 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 04/27/2010 12:58 PM, Konrad Rzeszutek Wilk wrote:
> On Tue, Apr 27, 2010 at 11:24:42AM -0400, Prarit Bhargava wrote:
>
>> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
>> xen guests have irq_desc->chip_data = NULL.
>>
> Can you provide a short example of test scenario? As in what I should do
> to reproduce this problem?
>
Take the latest upstream (well ... to be honest, a bit older than that
because of some other bugs) -- take 2.6.33 and try to boot it as a PV
guest. I'm using a RHEL5 Xen HV fwiw ...
P.
>> Test for NULL chip_data pointer before attempting to complete an irq move.
>>
>> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
>> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
>>
>> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
>> index 127b871..eb2789c 100644
>> --- a/arch/x86/kernel/apic/io_apic.c
>> +++ b/arch/x86/kernel/apic/io_apic.c
>> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
>> struct irq_desc *desc = irq_to_desc(irq);
>> struct irq_cfg *cfg = desc->chip_data;
>>
>> + if (!cfg)
>> + return;
>> +
>> __irq_complete_move(&desc, cfg->vector);
>> }
>> #else
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
>>
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 17:09 ` Prarit Bhargava
@ 2010-04-27 17:59 ` Andrew Jones
2010-04-27 18:34 ` Konrad Rzeszutek Wilk
1 sibling, 0 replies; 20+ messages in thread
From: Andrew Jones @ 2010-04-27 17:59 UTC (permalink / raw)
To: Prarit Bhargava
Cc: Konrad Rzeszutek Wilk, linux-kernel, suresh.b.siddha, x86, clalance
On 04/27/2010 07:09 PM, Prarit Bhargava wrote:
>
>
> On 04/27/2010 12:58 PM, Konrad Rzeszutek Wilk wrote:
>> On Tue, Apr 27, 2010 at 11:24:42AM -0400, Prarit Bhargava wrote:
>>
>>> Upstream PV guests fail to boot because of a NULL pointer. It is
>>> possible that
>>> xen guests have irq_desc->chip_data = NULL.
>>>
>> Can you provide a short example of test scenario? As in what I should do
>> to reproduce this problem?
>>
>
> Take the latest upstream (well ... to be honest, a bit older than that
> because of some other bugs) -- take 2.6.33 and try to boot it as a PV
> guest. I'm using a RHEL5 Xen HV fwiw ...
>
> P.
Another ingredient is to boot the guest with a configuration where its
maxvcpus is greater than its vcpus. If you have RHEL 5.5 userspace then
you can create a config with lines like this
maxvcpus = 4
vcpus = 2
with that you'll crash on boot. Then you can check that
irq_force_complete_move is on the stack if you have "preserve" for
on_crash and use xenctx to look at the state of the vcpus.
If the Xen you're using doesn't support the maxvcpus var, then I believe
you can do the same principle, but in a different way, using the
vcpus_avail var. Or, you can boot with > 1 vcpus and then attempt to
remove one with 'xm vcpu-set'.
Andrew
>
>>> Test for NULL chip_data pointer before attempting to complete an irq
>>> move.
>>>
>>> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
>>> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
>>>
>>> diff --git a/arch/x86/kernel/apic/io_apic.c
>>> b/arch/x86/kernel/apic/io_apic.c
>>> index 127b871..eb2789c 100644
>>> --- a/arch/x86/kernel/apic/io_apic.c
>>> +++ b/arch/x86/kernel/apic/io_apic.c
>>> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
>>> struct irq_desc *desc = irq_to_desc(irq);
>>> struct irq_cfg *cfg = desc->chip_data;
>>>
>>> + if (!cfg)
>>> + return;
>>> +
>>> __irq_complete_move(&desc, cfg->vector);
>>> }
>>> #else
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe
>>> linux-kernel" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at http://www.tux.org/lkml/
>>>
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 17:09 ` Prarit Bhargava
2010-04-27 17:59 ` Andrew Jones
@ 2010-04-27 18:34 ` Konrad Rzeszutek Wilk
2010-04-27 18:47 ` Prarit Bhargava
1 sibling, 1 reply; 20+ messages in thread
From: Konrad Rzeszutek Wilk @ 2010-04-27 18:34 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
>> Can you provide a short example of test scenario? As in what I should do
>> to reproduce this problem?
>>
>
> Take the latest upstream (well ... to be honest, a bit older than that
> because of some other bugs) -- take 2.6.33 and try to boot it as a PV
2.6.34-rc5 PV boots under Xen for me (and pretty much since 2.6.33 +
Suresh fix for the CONFIG_RODATA_MARK).
Perhaps I am missing some of the .config options you have set that make it not work?
The irqbalance daemon looks to be running - but I think you are hitting
this during bootup? How long do you have to wait for this to trigger?
How many CPUs did you assign to your guest?
What are the "other bugs" you speak off?
> guest. I'm using a RHEL5 Xen HV fwiw ...
OK, so your control domain is RHEL5. Mine is the Jeremy's xen/next one
(2.6.32). Let me try to compile RHEL5 under FC11 - any tricks necessary
to do that?
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 18:34 ` Konrad Rzeszutek Wilk
@ 2010-04-27 18:47 ` Prarit Bhargava
2010-05-03 19:16 ` Konrad Rzeszutek Wilk
0 siblings, 1 reply; 20+ messages in thread
From: Prarit Bhargava @ 2010-04-27 18:47 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 04/27/2010 02:34 PM, Konrad Rzeszutek Wilk wrote:
>>> Can you provide a short example of test scenario? As in what I should do
>>> to reproduce this problem?
>>>
>>>
>> Take the latest upstream (well ... to be honest, a bit older than that
>> because of some other bugs) -- take 2.6.33 and try to boot it as a PV
>>
> 2.6.34-rc5 PV boots under Xen for me (and pretty much since 2.6.33 +
> Suresh fix for the CONFIG_RODATA_MARK).
>
> Perhaps I am missing some of the .config options you have set that make it not work?
>
> The irqbalance daemon looks to be running - but I think you are hitting
> this during bootup? How long do you have to wait for this to trigger?
>
>
It happens during bootup. I don't have a 2.6.33 vanilla panic handy
but I do have one from an earlier 2.6.32...
rip: ffffffff81256f45 delay_tsc+0x45
rsp: ffff8800fac95a98
rax: fffffffff6ef46d0 rbx: 00000002 rcx: f6ef46d0 rdx: 0010850c
rsi: 002b3bb6 rdi: 002b3bcc rbp: ffff8800fac95ab8
r8: ffffffff r9: 00000002 r10: 00000002 r11: 00000000
r12: fffffffff6dec1c4 r13: 00000002 r14: 002b3bcc r15: 00000001
cs: 0000e033 ds: 00000000 fs: 00000000 gs: 00000000
Stack:
000000000002ef45 ffff8800fac95c88 0000000000000009 ffff8800fac93540
ffff8800fac95ac8 ffffffff81256ef6 ffff8800fac95b48 ffffffff814c6341
0000000000000010 ffff8800fac95b38 ffff880000000008 ffff8800fac95b58
ffff8800fac95b08 a22d306b065d4a66 0000000000000000 0000000000000000
Code:
f3 90 65 8b 1c 25 d8 e3 00 00 44 39 eb 75 23 66 66 90 0f ae e8<e8> 46 3d dc ff
66 90 48 98 48 89
Call Trace:
[<ffffffff81256f45>] delay_tsc+0x45<--
[<ffffffff81256ef6>] __const_udelay+0x46
[<ffffffff814c6341>] panic+0x135
[<ffffffff814ca23c>] oops_end+0xdc
[<ffffffff81042272>] no_context+0xf2
[<ffffffff8125946c>] __bitmap_weight+0x8c
[<ffffffff81042505>] __bad_area_nosemaphore+0x125
[<ffffffff8105fad4>] find_busiest_group+0x254
[<ffffffff810425d3>] bad_area_nosemaphore+0x13
[<ffffffff814cbccf>] do_page_fault+0x2ef
[<ffffffff814c9595>] page_fault+0x25
[<ffffffff810302f2>] irq_force_complete_move+0x12
[<ffffffff81015214>] fixup_irqs+0xa4
[<ffffffff8102ce59>] cpu_disable_common+0x1a9
[<ffffffff8100f9c2>] check_events+0x12
[<ffffffff810c2550>] __stop_machine+0x120
[<ffffffff8100ff75>] xen_cpu_disable+0x25
[<ffffffff814b0427>] take_cpu_down+0x17
[<ffffffff810c25f9>] stop_cpu+0xa9
[<ffffffff8108869d>] worker_thread+0x16d
[<ffffffff8100f19d>] xen_force_evtchn_callback+0xd
[<ffffffff8108dd00>] wake_up_bit+0x40
[<ffffffff814c90f6>] _spin_unlock_irqrestore+0x16
[<ffffffff81088530>] create_workqueue_thread+0xd0
[<ffffffff8108d9a6>] kthread+0x96
[<ffffffff8101418a>] child_rip+0xa
[<ffffffff81013351>] int_ret_from_sys_call+0x7
[<ffffffff81013add>] retint_restore_args+0x5
[<ffffffff81014180>] kernel_thread+0xe0
> How many CPUs did you assign to your guest?
>
>
It didn't matter as long as vcpus >1 and maxcpus > vcpus.
> What are the "other bugs" you speak off?
>
I got a different panic (which I've yet to resolve).
>
>> guest. I'm using a RHEL5 Xen HV fwiw ...
>>
> OK, so your control domain is RHEL5. Mine is the Jeremy's xen/next one
> (2.6.32). Let me try to compile RHEL5 under FC11 - any tricks necessary
> to do that?
>
I haven't tried it -- it might work :)
Also, did you try booting with maxvcpus > vcpus as drjones suggested ?
P.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-27 15:24 [PATCH] Fix NULL pointer for Xen guests Prarit Bhargava
2010-04-27 16:58 ` [LKML] " Konrad Rzeszutek Wilk
@ 2010-04-28 18:26 ` Andrew Morton
2010-04-28 18:29 ` Prarit Bhargava
2010-04-30 20:55 ` H. Peter Anvin
2010-04-30 21:36 ` [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() " tip-bot for Prarit Bhargava
3 siblings, 1 reply; 20+ messages in thread
From: Andrew Morton @ 2010-04-28 18:26 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On Tue, 27 Apr 2010 11:24:42 -0400
Prarit Bhargava <prarit@redhat.com> wrote:
> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
> xen guests have irq_desc->chip_data = NULL.
>
> Test for NULL chip_data pointer before attempting to complete an irq move.
>
> Signed-off-by: Prarit Bhargava <prarit@redhat.com>
> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
>
> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> index 127b871..eb2789c 100644
> --- a/arch/x86/kernel/apic/io_apic.c
> +++ b/arch/x86/kernel/apic/io_apic.c
> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> struct irq_desc *desc = irq_to_desc(irq);
> struct irq_cfg *cfg = desc->chip_data;
>
> + if (!cfg)
> + return;
> +
> __irq_complete_move(&desc, cfg->vector);
> }
> #else
I assume this is needed for 2.6.34?
What about 2.6.33.x and earlier?
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-28 18:26 ` Andrew Morton
@ 2010-04-28 18:29 ` Prarit Bhargava
2010-04-28 18:42 ` Suresh Siddha
2010-04-28 18:50 ` Andrew Morton
0 siblings, 2 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-04-28 18:29 UTC (permalink / raw)
To: Andrew Morton; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 04/28/2010 02:26 PM, Andrew Morton wrote:
> On Tue, 27 Apr 2010 11:24:42 -0400
> Prarit Bhargava<prarit@redhat.com> wrote:
>
>
>> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
>> xen guests have irq_desc->chip_data = NULL.
>>
>> Test for NULL chip_data pointer before attempting to complete an irq move.
>>
>> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
>> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
>>
>> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
>> index 127b871..eb2789c 100644
>> --- a/arch/x86/kernel/apic/io_apic.c
>> +++ b/arch/x86/kernel/apic/io_apic.c
>> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
>> struct irq_desc *desc = irq_to_desc(irq);
>> struct irq_cfg *cfg = desc->chip_data;
>>
>> + if (!cfg)
>> + return;
>> +
>> __irq_complete_move(&desc, cfg->vector);
>> }
>> #else
>>
> I assume this is needed for 2.6.34?
>
> What about 2.6.33.x and earlier?
>
Hey Andrew,
I actually pinged Chris Wright to see about including this in the
-stable branches. I haven't heard anything back so I'll reping him.
P.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-28 18:29 ` Prarit Bhargava
@ 2010-04-28 18:42 ` Suresh Siddha
2010-04-28 18:50 ` Andrew Morton
1 sibling, 0 replies; 20+ messages in thread
From: Suresh Siddha @ 2010-04-28 18:42 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: Andrew Morton, linux-kernel, x86, clalance, drjones
On Wed, 2010-04-28 at 11:29 -0700, Prarit Bhargava wrote:
>
> On 04/28/2010 02:26 PM, Andrew Morton wrote:
> > On Tue, 27 Apr 2010 11:24:42 -0400
> > Prarit Bhargava<prarit@redhat.com> wrote:
> >
> >
> >> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
> >> xen guests have irq_desc->chip_data = NULL.
> >>
> >> Test for NULL chip_data pointer before attempting to complete an irq move.
> >>
> >> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
> >> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
> >>
> >> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> >> index 127b871..eb2789c 100644
> >> --- a/arch/x86/kernel/apic/io_apic.c
> >> +++ b/arch/x86/kernel/apic/io_apic.c
> >> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> >> struct irq_desc *desc = irq_to_desc(irq);
> >> struct irq_cfg *cfg = desc->chip_data;
> >>
> >> + if (!cfg)
> >> + return;
> >> +
> >> __irq_complete_move(&desc, cfg->vector);
> >> }
> >> #else
> >>
> > I assume this is needed for 2.6.34?
> >
> > What about 2.6.33.x and earlier?
> >
>
> Hey Andrew,
>
> I actually pinged Chris Wright to see about including this in the
> -stable branches. I haven't heard anything back so I'll reping him.
It will be applicable for 2.6.33 and beyond.
thanks,
suresh
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-28 18:29 ` Prarit Bhargava
2010-04-28 18:42 ` Suresh Siddha
@ 2010-04-28 18:50 ` Andrew Morton
2010-04-28 19:15 ` [stable] " Greg KH
1 sibling, 1 reply; 20+ messages in thread
From: Andrew Morton @ 2010-04-28 18:50 UTC (permalink / raw)
To: Prarit Bhargava
Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones, stable
On Wed, 28 Apr 2010 14:29:06 -0400
Prarit Bhargava <prarit@redhat.com> wrote:
>
>
> On 04/28/2010 02:26 PM, Andrew Morton wrote:
> > On Tue, 27 Apr 2010 11:24:42 -0400
> > Prarit Bhargava<prarit@redhat.com> wrote:
> >
> >
> >> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
> >> xen guests have irq_desc->chip_data = NULL.
> >>
> >> Test for NULL chip_data pointer before attempting to complete an irq move.
> >>
> >> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
> >> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
> >>
> >> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> >> index 127b871..eb2789c 100644
> >> --- a/arch/x86/kernel/apic/io_apic.c
> >> +++ b/arch/x86/kernel/apic/io_apic.c
> >> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> >> struct irq_desc *desc = irq_to_desc(irq);
> >> struct irq_cfg *cfg = desc->chip_data;
> >>
> >> + if (!cfg)
> >> + return;
> >> +
> >> __irq_complete_move(&desc, cfg->vector);
> >> }
> >> #else
> >>
> > I assume this is needed for 2.6.34?
> >
> > What about 2.6.33.x and earlier?
> >
>
> Hey Andrew,
>
> I actually pinged Chris Wright to see about including this in the
> -stable branches. I haven't heard anything back so I'll reping him.
>
Well. Pinging people offlist isn't very reliable. Put
Cc: <stable@kernel.org>
at the end of the changelog and cc stable@kernel.org on the original
patch and then the patch will reliably receive consideration for
backporting.
I have added Cc:<stable@kernel.org> to my copy of the patch, so the
-stable guys will at least see it when I drop it after it is merged.
But if the x86 maintainers were to merge your patch as you sent it, it
would have no Cc: <stable@kernel.org> when it goes into Linus's tree.
I worry that if the -stable maintainer see me drop a patch, but the
patch in Linus's tree doesn't have the stable tag, they might not merge
the fix into -stable. I bugged them about this scenario recently and
the reply was a bit waffly ;)
By far the safest thing to do is to include the stable tag in your
changelog right at the outset.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [stable] [PATCH] Fix NULL pointer for Xen guests
2010-04-28 18:50 ` Andrew Morton
@ 2010-04-28 19:15 ` Greg KH
0 siblings, 0 replies; 20+ messages in thread
From: Greg KH @ 2010-04-28 19:15 UTC (permalink / raw)
To: Andrew Morton
Cc: Prarit Bhargava, drjones, suresh.b.siddha, x86, linux-kernel,
clalance, stable
On Wed, Apr 28, 2010 at 11:50:39AM -0700, Andrew Morton wrote:
> I worry that if the -stable maintainer see me drop a patch, but the
> patch in Linus's tree doesn't have the stable tag, they might not merge
> the fix into -stable. I bugged them about this scenario recently and
> the reply was a bit waffly ;)
It was?
I try my best, that if I see you drop a patch, to go dig through Linus's
tree to find if it landed there. If not, I leave it in my queue, and do
that for a few releases. If after a long time (like 6 months) I either
ping someone, or just drop it from my queue as I guessed that someone
dropped it for some reason.
If I miss one of these, please let me know.
> By far the safest thing to do is to include the stable tag in your
> changelog right at the outset.
Yes, that's the _easiest_ and will not get lost.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-27 15:24 [PATCH] Fix NULL pointer for Xen guests Prarit Bhargava
2010-04-27 16:58 ` [LKML] " Konrad Rzeszutek Wilk
2010-04-28 18:26 ` Andrew Morton
@ 2010-04-30 20:55 ` H. Peter Anvin
2010-04-30 21:33 ` H. Peter Anvin
2010-04-30 22:01 ` Prarit Bhargava
2010-04-30 21:36 ` [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() " tip-bot for Prarit Bhargava
3 siblings, 2 replies; 20+ messages in thread
From: H. Peter Anvin @ 2010-04-30 20:55 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
This looks like it should be tagged stable for 2.6.33. Is that correct?
-hpa
On 04/27/2010 08:24 AM, Prarit Bhargava wrote:
> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
> xen guests have irq_desc->chip_data = NULL.
>
> Test for NULL chip_data pointer before attempting to complete an irq move.
>
> Signed-off-by: Prarit Bhargava <prarit@redhat.com>
> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
>
> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> index 127b871..eb2789c 100644
> --- a/arch/x86/kernel/apic/io_apic.c
> +++ b/arch/x86/kernel/apic/io_apic.c
> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> struct irq_desc *desc = irq_to_desc(irq);
> struct irq_cfg *cfg = desc->chip_data;
>
> + if (!cfg)
> + return;
> +
> __irq_complete_move(&desc, cfg->vector);
> }
> #else
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-30 20:55 ` H. Peter Anvin
@ 2010-04-30 21:33 ` H. Peter Anvin
2010-04-30 22:01 ` Prarit Bhargava
1 sibling, 0 replies; 20+ messages in thread
From: H. Peter Anvin @ 2010-04-30 21:33 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 04/30/2010 01:55 PM, H. Peter Anvin wrote:
> This looks like it should be tagged stable for 2.6.33. Is that correct?
>
> -hpa
Nevermind... see it has already been discussed.
-hpa
^ permalink raw reply [flat|nested] 20+ messages in thread
* [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
2010-04-27 15:24 [PATCH] Fix NULL pointer for Xen guests Prarit Bhargava
` (2 preceding siblings ...)
2010-04-30 20:55 ` H. Peter Anvin
@ 2010-04-30 21:36 ` tip-bot for Prarit Bhargava
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
3 siblings, 1 reply; 20+ messages in thread
From: tip-bot for Prarit Bhargava @ 2010-04-30 21:36 UTC (permalink / raw)
To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, suresh.b.siddha, tglx, prarit
Commit-ID: bbd391a15d82e14efe9d69ba64cadb855b061dba
Gitweb: http://git.kernel.org/tip/bbd391a15d82e14efe9d69ba64cadb855b061dba
Author: Prarit Bhargava <prarit@redhat.com>
AuthorDate: Tue, 27 Apr 2010 11:24:42 -0400
Committer: H. Peter Anvin <hpa@zytor.com>
CommitDate: Fri, 30 Apr 2010 14:31:38 -0700
x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
Upstream PV guests fail to boot because of a NULL pointer in
irq_force_complete_move(). It is possible that xen guests have
irq_desc->chip_data = NULL.
Test for NULL chip_data pointer before attempting to complete an irq move.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
LKML-Reference: <20100427152434.16193.49104.sendpatchset@prarit.bos.redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org> [2.6.33]
---
arch/x86/kernel/apic/io_apic.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 127b871..eb2789c 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
struct irq_desc *desc = irq_to_desc(irq);
struct irq_cfg *cfg = desc->chip_data;
+ if (!cfg)
+ return;
+
__irq_complete_move(&desc, cfg->vector);
}
#else
^ permalink raw reply related [flat|nested] 20+ messages in thread
* Re: [PATCH] Fix NULL pointer for Xen guests
2010-04-30 20:55 ` H. Peter Anvin
2010-04-30 21:33 ` H. Peter Anvin
@ 2010-04-30 22:01 ` Prarit Bhargava
1 sibling, 0 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-04-30 22:01 UTC (permalink / raw)
To: H. Peter Anvin; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 04/30/2010 04:55 PM, H. Peter Anvin wrote:
> This looks like it should be tagged stable for 2.6.33. Is that correct?
>
>
Yes.
P.
> -hpa
>
> On 04/27/2010 08:24 AM, Prarit Bhargava wrote:
>
>> Upstream PV guests fail to boot because of a NULL pointer. It is possible that
>> xen guests have irq_desc->chip_data = NULL.
>>
>> Test for NULL chip_data pointer before attempting to complete an irq move.
>>
>> Signed-off-by: Prarit Bhargava<prarit@redhat.com>
>> Acked-by: Suresh Siddha<suresh.b.siddha@intel.com>
>>
>> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
>> index 127b871..eb2789c 100644
>> --- a/arch/x86/kernel/apic/io_apic.c
>> +++ b/arch/x86/kernel/apic/io_apic.c
>> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
>> struct irq_desc *desc = irq_to_desc(irq);
>> struct irq_cfg *cfg = desc->chip_data;
>>
>> + if (!cfg)
>> + return;
>> +
>> __irq_complete_move(&desc, cfg->vector);
>> }
>> #else
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
>>
>
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-04-27 18:47 ` Prarit Bhargava
@ 2010-05-03 19:16 ` Konrad Rzeszutek Wilk
2010-05-03 19:56 ` Prarit Bhargava
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
0 siblings, 2 replies; 20+ messages in thread
From: Konrad Rzeszutek Wilk @ 2010-05-03 19:16 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
>> OK, so your control domain is RHEL5. Mine is the Jeremy's xen/next one
>> (2.6.32). Let me try to compile RHEL5 under FC11 - any tricks necessary
>> to do that?
>>
>
> I haven't tried it -- it might work :)
>
> Also, did you try booting with maxvcpus > vcpus as drjones suggested ?
Yes. No luck reproducing the crash/panic. I am just not seeing the failure you
guys are seeing.
Let me build once more 2.6.33 vanilla + CONFIG_DEBUG_MARK_RODATA=n) and check
this. And also install a vanilla RHEL5 dom0 as it looks impossible to
compile a 2.6.18-era kernel under FC11.
The Xen I am using is xen-unstable - so 4.0.1. I know that the IRQ balance
code in the Xen hypervisor was fixed in 4.0 (it used to run out of
context - now it runs in the IRQ context). Maybe this bug you are seeing
(and have the fix for) is just a red-heering?
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-05-03 19:16 ` Konrad Rzeszutek Wilk
@ 2010-05-03 19:56 ` Prarit Bhargava
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
1 sibling, 0 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-05-03 19:56 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On 05/03/2010 03:16 PM, Konrad Rzeszutek Wilk wrote:
>>> OK, so your control domain is RHEL5. Mine is the Jeremy's xen/next one
>>> (2.6.32). Let me try to compile RHEL5 under FC11 - any tricks necessary
>>> to do that?
>>>
>>>
>> I haven't tried it -- it might work :)
>>
>> Also, did you try booting with maxvcpus> vcpus as drjones suggested ?
>>
> Yes. No luck reproducing the crash/panic. I am just not seeing the failure you
> guys are seeing.
>
> Let me build once more 2.6.33 vanilla + CONFIG_DEBUG_MARK_RODATA=n) and check
> this. And also install a vanilla RHEL5 dom0 as it looks impossible to
> compile a 2.6.18-era kernel under FC11.
>
Let me try reproducing this on FC11 + 2.6.33.
P.
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-05-03 19:16 ` Konrad Rzeszutek Wilk
2010-05-03 19:56 ` Prarit Bhargava
@ 2010-05-04 15:02 ` Konrad Rzeszutek Wilk
2010-05-04 15:21 ` Prarit Bhargava
1 sibling, 1 reply; 20+ messages in thread
From: Konrad Rzeszutek Wilk @ 2010-05-04 15:02 UTC (permalink / raw)
To: Prarit Bhargava; +Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
On Mon, May 03, 2010 at 03:16:34PM -0400, Konrad Rzeszutek Wilk wrote:
> >> OK, so your control domain is RHEL5. Mine is the Jeremy's xen/next one
> >> (2.6.32). Let me try to compile RHEL5 under FC11 - any tricks necessary
> >> to do that?
> >>
> >
> > I haven't tried it -- it might work :)
> >
> > Also, did you try booting with maxvcpus > vcpus as drjones suggested ?
>
> Yes. No luck reproducing the crash/panic. I am just not seeing the failure you
> guys are seeing.
>
> Let me build once more 2.6.33 vanilla + CONFIG_DEBUG_MARK_RODATA=n) and check
> this. And also install a vanilla RHEL5 dom0 as it looks impossible to
> compile a 2.6.18-era kernel under FC11.
Rebuilding everything from scratch did it. I am seeing a similar
failure where xenctx reports:
Call Trace:
[<ffffffff8107f780>] stop_cpu+0xc6 <--
[<ffffffff8105520e>] worker_thread+0x15d
[<ffffffff8107f6ba>] __stop_machine+0x106
[<ffffffff81058afb>] wake_up_bit+0x25
[<ffffffff81038720>] spin_unlock_irqrestore+0x9
[<ffffffff810550b1>] spin_lock_irq+0xb
[<ffffffff810586cb>] kthread+0x7a
[<ffffffff8100a964>] kernel_thread_helper+0x4
[<ffffffff81009d61>] int_ret_from_sys_call+0x7
[<ffffffff814033dd>] retint_restore_args+0x5
[<ffffffff8100a960>] gs_change+0x13
With this guest file:
kernel = "/mnt/lab/vs11/vmlinuz"
ramdisk = "/mnt/lab/vs11/initramfs.cpio.gz"
memory = 2048
maxvcpus = 4
vcpus = 2
vif = [ 'mac=00:0F:4B:00:00:71, bridge=switch' ]
vfb = [ 'vnc=1, vnclisten=0.0.0.0,vncunused=1']
root = "debug loglevel=10 plymouth:splash=solar plymouth:debug norm console=hvc0 initcall_debug"
This is with the latest linux kernel:
d93ac51c7a129db7a1431d859a3ef45a0b1f3fc5 (Merge branch 'for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client)
With your patch the PV guests keeps on going.
So:
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>
> The Xen I am using is xen-unstable - so 4.0.1. I know that the IRQ balance
> code in the Xen hypervisor was fixed in 4.0 (it used to run out of
> context - now it runs in the IRQ context). Maybe this bug you are seeing
> (and have the fix for) is just a red-heering?
Interestingly enough, I couldn't reproduce this on my Intel box, but on
a AMD box with a very wacked TSC (cpu MHz : 2795681.405) I can
reproduce this.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
2010-04-30 21:36 ` [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() " tip-bot for Prarit Bhargava
@ 2010-05-04 15:02 ` Konrad Rzeszutek Wilk
0 siblings, 0 replies; 20+ messages in thread
From: Konrad Rzeszutek Wilk @ 2010-05-04 15:02 UTC (permalink / raw)
To: mingo, hpa, linux-kernel, suresh.b.siddha, tglx, prarit; +Cc: linux-tip-commits
On Fri, Apr 30, 2010 at 09:36:42PM +0000, tip-bot for Prarit Bhargava wrote:
> Commit-ID: bbd391a15d82e14efe9d69ba64cadb855b061dba
> Gitweb: http://git.kernel.org/tip/bbd391a15d82e14efe9d69ba64cadb855b061dba
> Author: Prarit Bhargava <prarit@redhat.com>
> AuthorDate: Tue, 27 Apr 2010 11:24:42 -0400
> Committer: H. Peter Anvin <hpa@zytor.com>
> CommitDate: Fri, 30 Apr 2010 14:31:38 -0700
>
> x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
>
> Upstream PV guests fail to boot because of a NULL pointer in
> irq_force_complete_move(). It is possible that xen guests have
> irq_desc->chip_data = NULL.
>
> Test for NULL chip_data pointer before attempting to complete an irq move.
>
> Signed-off-by: Prarit Bhargava <prarit@redhat.com>
> LKML-Reference: <20100427152434.16193.49104.sendpatchset@prarit.bos.redhat.com>
> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Cc: <stable@kernel.org> [2.6.33]
> ---
> arch/x86/kernel/apic/io_apic.c | 3 +++
> 1 files changed, 3 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
> index 127b871..eb2789c 100644
> --- a/arch/x86/kernel/apic/io_apic.c
> +++ b/arch/x86/kernel/apic/io_apic.c
> @@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
> struct irq_desc *desc = irq_to_desc(irq);
> struct irq_cfg *cfg = desc->chip_data;
>
> + if (!cfg)
> + return;
> +
> __irq_complete_move(&desc, cfg->vector);
> }
> #else
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 20+ messages in thread
* Re: [LKML] Re: [LKML] [PATCH] Fix NULL pointer for Xen guests
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
@ 2010-05-04 15:21 ` Prarit Bhargava
0 siblings, 0 replies; 20+ messages in thread
From: Prarit Bhargava @ 2010-05-04 15:21 UTC (permalink / raw)
To: Konrad Rzeszutek Wilk
Cc: linux-kernel, suresh.b.siddha, x86, clalance, drjones
> Interestingly enough, I couldn't reproduce this on my Intel box, but on
> a AMD box with a very wacked TSC (cpu MHz : 2795681.405) I can
> reproduce this.
>
>
Huh ... that's odd. I'll grab a dinar based system and see if I can
reproduce it there. It would be interesting to know what the
differences are.
P.
^ permalink raw reply [flat|nested] 20+ messages in thread
end of thread, other threads:[~2010-05-04 15:23 UTC | newest]
Thread overview: 20+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-04-27 15:24 [PATCH] Fix NULL pointer for Xen guests Prarit Bhargava
2010-04-27 16:58 ` [LKML] " Konrad Rzeszutek Wilk
2010-04-27 17:09 ` Prarit Bhargava
2010-04-27 17:59 ` Andrew Jones
2010-04-27 18:34 ` Konrad Rzeszutek Wilk
2010-04-27 18:47 ` Prarit Bhargava
2010-05-03 19:16 ` Konrad Rzeszutek Wilk
2010-05-03 19:56 ` Prarit Bhargava
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
2010-05-04 15:21 ` Prarit Bhargava
2010-04-28 18:26 ` Andrew Morton
2010-04-28 18:29 ` Prarit Bhargava
2010-04-28 18:42 ` Suresh Siddha
2010-04-28 18:50 ` Andrew Morton
2010-04-28 19:15 ` [stable] " Greg KH
2010-04-30 20:55 ` H. Peter Anvin
2010-04-30 21:33 ` H. Peter Anvin
2010-04-30 22:01 ` Prarit Bhargava
2010-04-30 21:36 ` [tip:x86/urgent] x86: Fix NULL pointer access in irq_force_complete_move() " tip-bot for Prarit Bhargava
2010-05-04 15:02 ` [LKML] " Konrad Rzeszutek Wilk
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