Re: [PATCH] xen/arm: irq: Initialize the per-CPU IRQs while preparing the CPU

[Michal Orzel <michal.orzel@xxxxxxx>]

Hi Julien,

On 14.06.2022 11:41, Julien Grall wrote:
> From: Julien Grall <jgrall@xxxxxxxxxx>
> 
> Commit 5047cd1d5dea "xen/common: Use enhanced ASSERT_ALLOC_CONTEXT in
> xmalloc()" extended the checks in _xmalloc() to catch any use of the
> helpers from context with interrupts disabled.
> 
> Unfortunately, the rule is not followed when initializing the per-CPU
> IRQs:
> 
> (XEN) Xen call trace:
> (XEN)    [<002389f4>] _xmalloc+0xfc/0x314 (PC)
> (XEN)    [<00000000>] 00000000 (LR)
> (XEN)    [<0021a7c4>] init_one_irq_desc+0x48/0xd0
> (XEN)    [<002807a8>] irq.c#init_local_irq_data+0x48/0xa4
> (XEN)    [<00280834>] init_secondary_IRQ+0x10/0x2c
> (XEN)    [<00288fa4>] start_secondary+0x194/0x274
> (XEN)    [<40010170>] 40010170
> (XEN)
> (XEN)
> (XEN) ****************************************
> (XEN) Panic on CPU 2:
> (XEN) Assertion '!in_irq() && (local_irq_is_enabled() || num_online_cpus() <= 
> 1)' failed at common/xmalloc_tlsf.c:601
> (XEN) ****************************************
> 
> This is happening because zalloc_cpumask_var() may allocate memory
> if NR_CPUS is > 2 * sizeof(unsigned long).
> 
> Avoid the problem by allocate the per-CPU IRQs while preparing the
> CPU.
Shouldn't this be" by initializing the per-CPU IRQs while ..." ?
Either way this text is the same like in the previous patch so I think this is 
not correct.

Other than that:
Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>