Re: Patch "irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued" has been added to the 6.6-stable tree

[Sasha Levin <sashal@kernel.org>]

On Sun, Sep 08, 2024 at 04:27:10PM +0100, Marc Zyngier wrote:
>On Sun, 08 Sep 2024 14:36:37 +0100,
>Sasha Levin <sashal@kernel.org> wrote:
>>
>> This is a note to let you know that I've just added the patch titled
>>
>>     irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
>>
>> to the 6.6-stable tree which can be found at:
>>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>>
>> The filename of the patch is:
>>      irqchip-gic-v4-make-sure-a-vpe-is-locked-when-vmapp-.patch
>> and it can be found in the queue-6.6 subdirectory.
>>
>> If you, or anyone else, feels it should not be added to the stable tree,
>> please let <stable@vger.kernel.org> know about it.
>>
>>
>>
>> commit 1a232324773145ff7ce59b6a1b52b3247223f9d4
>> Author: Marc Zyngier <maz@kernel.org>
>> Date:   Fri Jul 5 10:31:55 2024 +0100
>>
>>     irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
>>
>>     [ Upstream commit a84a07fa3100d7ad46a3d6882af25a3df9c9e7e3 ]
>>
>>     In order to make sure that vpe->col_idx is correctly sampled when a VMAPP
>>     command is issued, the vpe_lock must be held for the VPE. This is now
>>     possible since the introduction of the per-VM vmapp_lock, which can be
>>     taken before vpe_lock in the correct locking order.
>>
>>     Signed-off-by: Marc Zyngier <maz@kernel.org>
>>     Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
>>     Tested-by: Nianyao Tang <tangnianyao@huawei.com>
>>     Link: https://lore.kernel.org/r/20240705093155.871070-4-maz@kernel.org
>>     Signed-off-by: Sasha Levin <sashal@kernel.org>
>>
>> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
>> index e25dea0e50c7..1e0f0e1bf481 100644
>> --- a/drivers/irqchip/irq-gic-v3-its.c
>> +++ b/drivers/irqchip/irq-gic-v3-its.c
>> @@ -1804,7 +1804,9 @@ static void its_map_vm(struct its_node *its, struct its_vm *vm)
>>  		for (i = 0; i < vm->nr_vpes; i++) {
>>  			struct its_vpe *vpe = vm->vpes[i];
>>
>> -			its_send_vmapp(its, vpe, true);
>> +			scoped_guard(raw_spinlock, &vpe->vpe_lock)
>> +				its_send_vmapp(its, vpe, true);
>> +
>>  			its_send_vinvall(its, vpe);
>>  		}
>>  	}
>> @@ -1825,8 +1827,10 @@ static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
>>  	if (!--vm->vlpi_count[its->list_nr]) {
>>  		int i;
>>
>> -		for (i = 0; i < vm->nr_vpes; i++)
>> +		for (i = 0; i < vm->nr_vpes; i++) {
>> +			guard(raw_spinlock)(&vm->vpes[i]->vpe_lock);
>>  			its_send_vmapp(its, vm->vpes[i], false);
>> +		}
>>  	}
>>
>>  	raw_spin_unlock_irqrestore(&vmovp_lock, flags);
>>
>
>No please.
>
>Not only you are missing the essential part of the series (the patch
>introducing the per-VM lock that this change relies on), you are also
>missing the fixes that followed.
>
>So please drop this patch from the 6.6 and 6.1 queues.

Will do, thanks!

-- 
Thanks,
Sasha