x86/irq: Call chip->irq_set_affinity in proper context
authorThomas Gleixner <tglx@linutronix.de>
Thu, 14 Jan 2016 07:43:38 +0000 (08:43 +0100)
committerThomas Gleixner <tglx@linutronix.de>
Fri, 15 Jan 2016 12:43:58 +0000 (13:43 +0100)
commite23b257c293ce4bcc8cabb2aa3097b6ed8a8261a
treee05376f96aaa28babe15029771536483dbf3c108
parent7030a7e9321166eef44c811fe4af4d460360d424
x86/irq: Call chip->irq_set_affinity in proper context

setup_ioapic_dest() calls irqchip->irq_set_affinity() completely
unprotected. That's wrong in several aspects:

 - it opens a race window where irq_set_affinity() can be interrupted and the
   irq chip left in unconsistent state.

 - it triggers a lockdep splat when we fix the vector race for 4.3+ because
   vector lock is taken with interrupts enabled.

The proper calling convention is irq descriptor lock held and interrupts
disabled.

Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jeremiah Mahler <jmmahler@gmail.com>
Cc: andy.shevchenko@gmail.com
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Joe Lawrence <joe.lawrence@stratus.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1601140919420.3575@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/apic/io_apic.c