Re: [patch 12/14] PCI: hv: Use tasklet_disable_in_atomic()

[Bjorn Helgaas]

On Tue, Mar 09, 2021 at 09:42:15AM +0100, Thomas Gleixner wrote:
> From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> 
> The hv_compose_msi_msg() callback in irq_chip::irq_compose_msi_msg is
> invoked via irq_chip_compose_msi_msg(), which itself is always invoked from
> atomic contexts from the guts of the interrupt core code.
> 
> There is no way to change this w/o rewriting the whole driver, so use
> tasklet_disable_in_atomic() which allows to make tasklet_disable()
> sleepable once the remaining atomic users are addressed.
> 
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
> Cc: Wei Liu <wei.liu@xxxxxxxxxx>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: linux-hyperv@xxxxxxxxxxxxxxx
> Cc: linux-pci@xxxxxxxxxxxxxxx

Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

It'd be ideal if you could merge this as a group.  Let me know if you
want me to do anything else.

> ---
>  drivers/pci/controller/pci-hyperv.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -1458,7 +1458,7 @@ static void hv_compose_msi_msg(struct ir
>  	 * Prevents hv_pci_onchannelcallback() from running concurrently
>  	 * in the tasklet.
>  	 */
> -	tasklet_disable(&channel->callback_event);
> +	tasklet_disable_in_atomic(&channel->callback_event);
>  
>  	/*
>  	 * Since this function is called with IRQ locks held, can't
>