| 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
| ||
|
Message-ID: <20100326150943.GA27702@elte.hu>
Date: Fri, 26 Mar 2010 16:09:43 +0100
From: Ingo Molnar <mingo@...e.hu>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Andrew Morton <akpm@...ux-foundation.org>
Subject: [GIT PULL] irq fixes
Linus,
Please pull the latest irq-fixes-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git irq-fixes-for-linus
Thanks,
Ingo
------------------>
Henrik Kretzschmar (1):
genirq: Move two IRQ functions from .init.text to .text
Thomas Gleixner (2):
genirq: Prevent oneshot irq thread race
genirq: Protect access to irq_desc->action in can_request_irq()
kernel/irq/chip.c | 35 ++++++++++++++++++++++++-----------
kernel/irq/manage.c | 22 ++++++++++++++++++++++
2 files changed, 46 insertions(+), 11 deletions(-)
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index d70394f..3c2d6e7 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -359,6 +359,23 @@ static inline void mask_ack_irq(struct irq_desc *desc, int irq)
if (desc->chip->ack)
desc->chip->ack(irq);
}
+ desc->status |= IRQ_MASKED;
+}
+
+static inline void mask_irq(struct irq_desc *desc, int irq)
+{
+ if (desc->chip->mask) {
+ desc->chip->mask(irq);
+ desc->status |= IRQ_MASKED;
+ }
+}
+
+static inline void unmask_irq(struct irq_desc *desc, int irq)
+{
+ if (desc->chip->unmask) {
+ desc->chip->unmask(irq);
+ desc->status &= ~IRQ_MASKED;
+ }
}
/*
@@ -484,10 +501,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
desc->status &= ~IRQ_INPROGRESS;
- if (unlikely(desc->status & IRQ_ONESHOT))
- desc->status |= IRQ_MASKED;
- else if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
- desc->chip->unmask(irq);
+ if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT)))
+ unmask_irq(desc, irq);
out_unlock:
raw_spin_unlock(&desc->lock);
}
@@ -524,8 +539,7 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
action = desc->action;
if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
desc->status |= IRQ_PENDING;
- if (desc->chip->mask)
- desc->chip->mask(irq);
+ mask_irq(desc, irq);
goto out;
}
@@ -593,7 +607,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
irqreturn_t action_ret;
if (unlikely(!action)) {
- desc->chip->mask(irq);
+ mask_irq(desc, irq);
goto out_unlock;
}
@@ -605,8 +619,7 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
if (unlikely((desc->status &
(IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
(IRQ_PENDING | IRQ_MASKED))) {
- desc->chip->unmask(irq);
- desc->status &= ~IRQ_MASKED;
+ unmask_irq(desc, irq);
}
desc->status &= ~IRQ_PENDING;
@@ -716,7 +729,7 @@ set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
__set_irq_handler(irq, handle, 0, name);
}
-void __init set_irq_noprobe(unsigned int irq)
+void set_irq_noprobe(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
unsigned long flags;
@@ -731,7 +744,7 @@ void __init set_irq_noprobe(unsigned int irq)
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
-void __init set_irq_probe(unsigned int irq)
+void set_irq_probe(unsigned int irq)
{
struct irq_desc *desc = irq_to_desc(irq);
unsigned long flags;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index eb6078c..398fda1 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -382,6 +382,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
{
struct irq_desc *desc = irq_to_desc(irq);
struct irqaction *action;
+ unsigned long flags;
if (!desc)
return 0;
@@ -389,11 +390,14 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
if (desc->status & IRQ_NOREQUEST)
return 0;
+ raw_spin_lock_irqsave(&desc->lock, flags);
action = desc->action;
if (action)
if (irqflags & action->flags & IRQF_SHARED)
action = NULL;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
return !action;
}
@@ -483,8 +487,26 @@ static int irq_wait_for_interrupt(struct irqaction *action)
*/
static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
{
+again:
chip_bus_lock(irq, desc);
raw_spin_lock_irq(&desc->lock);
+
+ /*
+ * Implausible though it may be we need to protect us against
+ * the following scenario:
+ *
+ * The thread is faster done than the hard interrupt handler
+ * on the other CPU. If we unmask the irq line then the
+ * interrupt can come in again and masks the line, leaves due
+ * to IRQ_INPROGRESS and the irq line is masked forever.
+ */
+ if (unlikely(desc->status & IRQ_INPROGRESS)) {
+ raw_spin_unlock_irq(&desc->lock);
+ chip_bus_sync_unlock(irq, desc);
+ cpu_relax();
+ goto again;
+ }
+
if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
desc->status &= ~IRQ_MASKED;
desc->chip->unmask(irq);
--
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/
Powered by blists - more mailing lists