linux-kernel - Re: [PATCH 1/5] cpumask: update irq_desc to use cpumask_var

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:	Wed, 07 Jan 2009 14:32:50 -0800
From:	Mike Travis <travis@....com>
To:	Yinghai Lu <yinghai@...nel.org>
CC:	Ingo Molnar <mingo@...hat.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>, Jack Steiner <steiner@....com>,
	linux-kernel@...r.kernel.org, Chris Wright <chrisw@...s-sol.org>,
	Jeremy Fitzhardinge <jeremy@...source.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>,
	virtualization@...ts.osdl.org, xen-devel@...ts.xensource.com
Subject: Re: [PATCH 1/5] cpumask: update irq_desc to use cpumask_var_t

Yinghai Lu wrote:
> On Wed, Jan 7, 2009 at 11:58 AM, Mike Travis <travis@....com> wrote:
> | --- linux-2.6-for-ingo.orig/kernel/irq/numa_migrate.c
> | +++ linux-2.6-for-ingo/kernel/irq/numa_migrate.c
> | @@ -46,6 +46,7 @@ static void init_copy_one_irq_desc(int i
> | 	desc->cpu = cpu;
> | 	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
> | 	init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
> |+	init_copy_desc_masks(old_desc, desc);
> | 	arch_init_copy_chip_data(old_desc, desc, cpu);
> | }
> |
> |@@ -76,11 +77,20 @@ static struct irq_desc *__real_move_irq_
> | 	node = cpu_to_node(cpu);
> | 	desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
> | 	if (!desc) {
> |-		printk(KERN_ERR "irq %d: can not get new irq_desc for migration.\n", irq);
> |+		printk(KERN_ERR "irq %d: can not get new irq_desc "
> |+				"for migration.\n", irq);
> | 		/* still use old one */
> | 		desc = old_desc;
> | 		goto out_unlock;
> | 	}
> |+	if (!init_alloc_desc_masks(desc, node, false)) {
> |+		printk(KERN_ERR "irq %d: can not get new irq_desc cpumask "
> |+				"for migration.\n", irq);
> |+		/* still use old one */
> |+		kfree(desc);
> |+		desc = old_desc;
> |+		goto out_unlock;
> |+	}
> | 	init_copy_one_irq_desc(irq, old_desc, desc, cpu);
> 
> desc new mask_var (allocated) aka the pointer is overwritten here...
> you may need to calling move init_alloc_desc_masks() into
> init_copy_one_irq_desc()

Wouldn't this in init_copy_one_irq_desc() take care  of that?

@@ -46,6 +46,7 @@ static void init_copy_one_irq_desc(int i
        desc->cpu = cpu;
        lockdep_set_class(&desc->lock, &irq_desc_lock_class);
        init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
+       init_copy_desc_masks(old_desc, desc);
        arch_init_copy_chip_data(old_desc, desc, cpu);

where:

static inline void init_copy_desc_masks(struct irq_desc *old_desc,
                                        struct irq_desc *new_desc)
{
#ifdef CONFIG_CPUMASKS_OFFSTACK
        cpumask_copy(new_desc->affinity, old_desc->affinity);

#ifdef CONFIG_GENERIC_PENDING_IRQ
        cpumask_copy(new_desc->pending_mask, old_desc->pending_mask);
#endif
#endif
}

In other words if the masks are not a cpumask[1] but instead a
*cpumask pointer, then the old masks are copied to the new desc/

Or am I missing your point?

Thanks!
Mike

> 
> | 	irq_desc_ptrs[irq] = desc;
> 
> YH
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/