linux-kernel - Re: [BUG 4.15-rc7] IRQ matrix management errors

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 16 Jan 2018 19:25:11 -0700
From:   Keith Busch <keith.busch@...el.com>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: Re: [BUG 4.15-rc7] IRQ matrix management errors

On Tue, Jan 16, 2018 at 12:20:18PM +0100, Thomas Gleixner wrote:
> 8<----------------------
> diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
> index f8b03bb8e725..3cc471beb50b 100644
> --- a/arch/x86/kernel/apic/vector.c
> +++ b/arch/x86/kernel/apic/vector.c
> @@ -542,14 +542,17 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
>  
>  		err = assign_irq_vector_policy(irqd, info);
>  		trace_vector_setup(virq + i, false, err);
> -		if (err)
> +		if (err) {
> +			irqd->chip_data = NULL;
> +			free_apic_chip_data(apicd);
>  			goto error;
> +		}
>  	}
>  
>  	return 0;
>  
>  error:
> -	x86_vector_free_irqs(domain, virq, i + 1);
> +	x86_vector_free_irqs(domain, virq, i);
>  	return err;
>  }
>  

The patch does indeed fix all the warnings and allows device binding to
succeed, albeit in a degraded performance mode. Despite that, this is
a good fix, and looks applicable to 4.4-stable, so:

Tested-by: Keith Busch <keith.busch@...el.com>

I'm still concerned assign_irq_vector_policy is failing. That has
interrupt allocation abandon MSI-x and fall back to legacy IRQ. 

Your patch does address my main concern, though. Are you comfortable
enough to queue this up for 4.15?

Thanks,
Keith