Re: [PATCH v2] xen/arm: gic-v3-lpi: Allocate the pending table while preparing the CPU

[Julien Grall <julien@xxxxxxx>]

Hi,

On 17/05/2022 09:58, Bertrand Marquis wrote:
> > On 16 May 2022, at 18:02, Julien Grall <julien@xxxxxxx> wrote:
> >
> > From: Julien Grall <jgrall@xxxxxxxxxx>
> >
> > Commit 88a037e2cfe1 "page_alloc: assert IRQs are enabled in heap
> > alloc/free" extended the checks in the buddy allocator to catch any
> > use of the helpers from context with interrupts disabled.
> >
> > Unfortunately, the rule is not followed in the LPI code when allocating
> > the pending table:
> >
> > (XEN) Xen call trace:
> > (XEN)    [<000000000022a678>] alloc_xenheap_pages+0x178/0x194 (PC)
> > (XEN)    [<000000000022a670>] alloc_xenheap_pages+0x170/0x194 (LR)
> > (XEN)    [<0000000000237770>] _xmalloc+0x144/0x294
> > (XEN)    [<00000000002378d4>] _xzalloc+0x14/0x30
> > (XEN)    [<000000000027b4e4>] gicv3_lpi_init_rdist+0x54/0x324
> > (XEN)    [<0000000000279898>] arch/arm/gic-v3.c#gicv3_cpu_init+0x128/0x46
> > (XEN)    [<0000000000279bfc>] 
> > arch/arm/gic-v3.c#gicv3_secondary_cpu_init+0x20/0x50
> > (XEN)    [<0000000000277054>] gic_init_secondary_cpu+0x18/0x30
> > (XEN)    [<0000000000284518>] start_secondary+0x1a8/0x234
> > (XEN)    [<0000010722aa4200>] 0000010722aa4200
> > (XEN)
> > (XEN)
> > (XEN) ****************************************
> > (XEN) Panic on CPU 2:
> > (XEN) Assertion '!in_irq() && (local_irq_is_enabled() || num_online_cpus() <= 
> > 1)' failed at common/page_alloc.c:2212
> > (XEN) ****************************************
> >
> > For now the patch extending the checks has been reverted, but it would
> > be good to re-introduce it (allocation with interrupt is not desirable).
> >
> > The logic is reworked to allocate the pending table when preparing the
> > CPU.
> >
> > Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx>
> With the print fixed as pointed by Michal you can add my:
> Reviewed-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>
Thanks!

> (Fix could be done on commit but that is up to you).
I have fixed it and committed it.

Cheers,

--
Julien Grall