From: Michael Neuling Date: Fri, 22 Apr 2016 04:57:48 +0000 (+1000) Subject: cxl: Keep IRQ mappings on context teardown X-Git-Tag: v4.6-rc6~2^2~2 X-Git-Url: http://git.cascardo.info/?a=commitdiff_plain;h=d6776bba44d9752f6cdf640046070e71ee4bba7b;p=cascardo%2Flinux.git cxl: Keep IRQ mappings on context teardown Keep IRQ mappings on context teardown. This won't leak IRQs as if we allocate the mapping again, the generic code will give the same mapping used last time. Doing this works around a race in the generic code. Masking the interrupt introduces a race which can crash the kernel or result in IRQ that is never EOIed. The lost of EOI results in all subsequent mappings to the same HW IRQ never receiving an interrupt. We've seen this race with cxl test cases which are doing heavy context startup and teardown at the same time as heavy interrupt load. A fix to the generic code is being investigated also. Signed-off-by: Michael Neuling Cc: stable@vger.kernel.org # 3.8 Tested-by: Andrew Donnellan Acked-by: Ian Munsie Tested-by: Vaibhav Jain Signed-off-by: Michael Ellerman --- diff --git a/drivers/misc/cxl/irq.c b/drivers/misc/cxl/irq.c index be646dc41a2c..8def4553acba 100644 --- a/drivers/misc/cxl/irq.c +++ b/drivers/misc/cxl/irq.c @@ -203,7 +203,6 @@ unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq, void cxl_unmap_irq(unsigned int virq, void *cookie) { free_irq(virq, cookie); - irq_dispose_mapping(virq); } int cxl_register_one_irq(struct cxl *adapter,