diff options
| author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2011-06-02 18:55:13 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2011-06-03 14:53:16 +0200 |
| commit | c5182b8867e189e14a8df5dbfcba1c73f286e061 (patch) | |
| tree | 89ac7169ab5009625770124e8b78549e69009ea1 | |
| parent | e7fbad300a7a6432238f086e3c9a61538a905858 (diff) | |
| download | linux-c5182b8867e189e14a8df5dbfcba1c73f286e061.tar.gz | |
genirq: Ensure we locate the passed IRQ in irq_alloc_descs()
When irq_alloc_descs() is called with no base IRQ specified then it will search for a range of IRQs starting from a specified base address. In the case where an IRQ is specified it still does this search in order to ensure that none of the requested range is already allocated and it still uses the from parameter to specify the base for the search. This means that in the case where a base is specified but from is zero (which is reasonable as any IRQ number is in the range specified by a zero from) the function will get confused and try to allocate the first suitably sized block of free IRQs it finds. Instead use a specified IRQ as the base address for the search, and insist that any from that is specified can support that IRQ. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Link: http://lkml.kernel.org/r/1307037313-15733-1-git-send-email-broonie@opensource.wolfsonmicro.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/irq/irqdesc.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index c7ddc87d6c87..4c60a50e66b2 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -344,6 +344,12 @@ irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node) if (!cnt) return -EINVAL; + if (irq >= 0) { + if (from > irq) + return -EINVAL; + from = irq; + } + mutex_lock(&sparse_irq_lock); start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS, |