[ I already send a similar patch to the list on May 29th ([RFC] Convert
sparse_irq_lock to raw_spinlock_t). ]
When allocating struct irq_desc we can get the memory before disabling the
interrupts.
[ 22.867664] BUG: sleeping function called from invalid context at
/usr/src/pa
ckages/BUILD/kernel-rt-2.6.31/linux-2.6.30/kernel/rtmutex.c:684
[ 22.867682] in_atomic(): 1, irqs_disabled(): 1, pid: 4084, name: ip
[ 22.867691] Pid: 4084, comm: ip Tainted: G N 2.6.31-rc7-rt8-20-rt
#
1
[ 22.867702] Call Trace:
[ 22.867727] [<ffffffff81011711>] try_stack_unwind+0x171/0x1c0
[ 22.867742] [<ffffffff8101002c>] dump_trace+0xac/0x2f0
[ 22.867755] [<ffffffff81011204>] show_trace_log_lvl+0x64/0x90
[ 22.867768] [<ffffffff81011253>] show_trace+0x23/0x40
[ 22.867782] [<ffffffff814de2be>] dump_stack+0x81/0xa3
[ 22.867793] [<ffffffff81057209>] __might_sleep+0x109/0x120
[ 22.867806] [<ffffffff814e18e1>] rt_spin_lock+0x41/0xb0
[ 22.867822] [<ffffffff811568fe>] _slab_irq_disable+0x5e/0x90
[ 22.867837] [<ffffffff811578c6>] kmem_cache_alloc_node+0x46/0x280
[ 22.867850] [<ffffffff81158efa>] __kmalloc_node+0x7a/0x160
[ 22.867868] [<ffffffff810df452>] kzalloc_node+0x22/0x40
[ 22.867884] [<ffffffff814c6c70>] irq_to_desc_alloc_node+0x100/0x1e0
[ 22.867899] [<ffffffff8102f9fc>] create_irq_nr+0x5c/0x150
[ 22.867913] [<ffffffff8102fbd2>] arch_setup_msi_irqs+0xe2/0x1d0
[ 22.867931] [<ffffffff8129ff20>] msi_capability_init+0x130/0x250
[ 22.867945] [<ffffffff812a0136>] pci_enable_msi_block+0xf6/0x150
[ 22.867977] [<ffffffffa026184a>] nv_request_irq+0x27a/0x430 [forcedeth]
[ 22.868001] [<ffffffffa0264f2d>] nv_open+0x3ad/0x610 [forcedeth]
[ 22.868020] [<ffffffff813ee052>] dev_open+0xf2/0x140
[ 22.868034] [<ffffffff813ed33c>] dev_change_flags+0xac/0x200
[ 22.868048] [<ffffffff813f9844>] do_setlink+0x2a4/0x460
[ 22.868061] [<ffffffff813fb3fb>] rtnl_newlink+0x49b/0x560
[ 22.868071] [<ffffffff813fad24>] rtnetlink_rcv_msg+0x1b4/0x270
[ 22.868083] [<ffffffff81412f59>] netlink_rcv_skb+0xa9/0xe0
[ 22.868094] [<ffffffff813fab46>] rtnetlink_rcv+0x36/0x60
[ 22.868103] [<ffffffff81412bbd>] netlink_unicast+0x2cd/0x2e0
[ 22.868121] [<ffffffff814139e4>] netlink_sendmsg+0x234/0x330
[ 22.868131] [<ffffffff813d7b06>] sock_sendmsg+0x116/0x160
[ 22.868142] [<ffffffff813d7d12>] sys_sendmsg+0x1c2/0x370
[ 22.868153] [<ffffffff8100c7c2>] system_call_fastpath+0x16/0x1b
[ 22.868176] [<00007fc1bf778220>] 0x7fc1bf778220
Signed-off-by: Jan Blunck <jblunck@xxxxxxx>
---
kernel/irq/handle.c | 46 ++++++++++++++++++++++++++++-----------
kernel/irq/internals.h | 1
kernel/irq/numa_migrate.c | 53 ++++++++++++++++++----------------------------
kernel/softirq.c | 6 +++++
4 files changed, 61 insertions(+), 45 deletions(-)
Index: b/kernel/irq/handle.c
===================================================================
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -126,6 +126,22 @@ static void init_one_irq_desc(int irq, s
arch_init_chip_data(desc, node);
}
+static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
+{
+ if (old_desc->kstat_irqs == desc->kstat_irqs)
+ return;
+
+ kfree(old_desc->kstat_irqs);
+ old_desc->kstat_irqs = NULL;
+}
+
+void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
+{
+ free_kstat_irqs(old_desc, desc);
+ free_desc_masks(old_desc, desc);
+ arch_free_chip_data(old_desc, desc);
+}
+
/*
* Protect the sparse_irqs:
*/
@@ -195,7 +211,7 @@ struct irq_desc *irq_to_desc(unsigned in
struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
{
- struct irq_desc *desc;
+ struct irq_desc *desc, *tmp;
unsigned long flags;
if (irq >= nr_irqs) {
@@ -208,26 +224,30 @@ struct irq_desc * __ref irq_to_desc_allo
if (desc)
return desc;
- atomic_spin_lock_irqsave(&sparse_irq_lock, flags);
-
- /* We have to check it to avoid races with another CPU */
- desc = irq_desc_ptrs[irq];
- if (desc)
- goto out_unlock;
-
if (slab_is_available())
- desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
+ tmp = kzalloc_node(sizeof(*tmp), GFP_ATOMIC, node);
else
- desc = alloc_bootmem_node(NODE_DATA(node), sizeof(*desc));
+ tmp = alloc_bootmem_node(NODE_DATA(node), sizeof(*tmp));
printk(KERN_DEBUG " alloc irq_desc for %d on node %d\n", irq, node);
- if (!desc) {
+ if (!tmp) {
printk(KERN_ERR "can not alloc irq_desc\n");
BUG_ON(1);
}
- init_one_irq_desc(irq, desc, node);
+ init_one_irq_desc(irq, tmp, node);
+
+ atomic_spin_lock_irqsave(&sparse_irq_lock, flags);
+
+ /* We have to check it to avoid races with another CPU */
+ desc = irq_desc_ptrs[irq];
+ if (desc) {
+ free_one_irq_desc(tmp, desc);
+ kfree(tmp);
+ goto out_unlock;
+ }
- irq_desc_ptrs[irq] = desc;
+ irq_desc_ptrs[irq] = tmp;
+ desc = tmp;
out_unlock:
atomic_spin_unlock_irqrestore(&sparse_irq_lock, flags);
Index: b/kernel/irq/internals.h
===================================================================
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -16,6 +16,7 @@ extern void __disable_irq(struct irq_des
extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
extern struct lock_class_key irq_desc_lock_class;
+extern void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc);
extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
extern void clear_kstat_irqs(struct irq_desc *desc);
extern atomic_spinlock_t sparse_irq_lock;
Index: b/kernel/irq/numa_migrate.c
===================================================================
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -24,15 +24,6 @@ static void init_copy_kstat_irqs(struct
nr * sizeof(*desc->kstat_irqs));
}
-static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
-{
- if (old_desc->kstat_irqs == desc->kstat_irqs)
- return;
-
- kfree(old_desc->kstat_irqs);
- old_desc->kstat_irqs = NULL;
-}
-
static bool init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
struct irq_desc *desc, int node)
{
@@ -51,46 +42,41 @@ static bool init_copy_one_irq_desc(int i
return true;
}
-static void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
-{
- free_kstat_irqs(old_desc, desc);
- free_desc_masks(old_desc, desc);
- arch_free_chip_data(old_desc, desc);
-}
-
static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
int node)
{
- struct irq_desc *desc;
+ struct irq_desc *desc, *tmp;
unsigned int irq;
unsigned long flags;
irq = old_desc->irq;
- atomic_spin_lock_irqsave(&sparse_irq_lock, flags);
-
- /* We have to check it to avoid races with another CPU */
- desc = irq_desc_ptrs[irq];
-
- if (desc && old_desc != desc)
- goto out_unlock;
-
- desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
- if (!desc) {
+ /* Allocate memory before disabling IRQs */
+ tmp = kzalloc_node(sizeof(*tmp), GFP_ATOMIC, node);
+ if (!tmp) {
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;
+ goto out;
}
- if (!init_copy_one_irq_desc(irq, old_desc, desc, node)) {
+ if (!init_copy_one_irq_desc(irq, old_desc, tmp, node)) {
/* still use old one */
- kfree(desc);
+ kfree(tmp);
desc = old_desc;
- goto out_unlock;
+ goto out;
}
- irq_desc_ptrs[irq] = desc;
+ atomic_spin_lock_irqsave(&sparse_irq_lock, flags);
+
+ /* We have to check it to avoid races with another CPU */
+ desc = irq_desc_ptrs[irq];
+
+ if (desc && old_desc != desc)
+ goto out_unlock;
+
+ irq_desc_ptrs[irq] = tmp;
+ desc = tmp;
atomic_spin_unlock_irqrestore(&sparse_irq_lock, flags);
/* free the old one */
@@ -102,6 +88,9 @@ static struct irq_desc *__real_move_irq_
out_unlock:
atomic_spin_unlock_irqrestore(&sparse_irq_lock, flags);
+ free_one_irq_desc(tmp, old_desc);
+ kfree(tmp);
+out:
return desc;
}
Index: b/kernel/softirq.c
===================================================================
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -1291,3 +1291,9 @@ int __weak arch_init_chip_data(struct ir
{
return 0;
}
+
+void __weak arch_free_chip_data(struct irq_desc *old_desc,
+ struct irq_desc *desc)
+{
+ return;
+}
Regards,
Jan
--
Jan Blunck <jblunck@xxxxxxx>
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