[PATCH v2] dma: Add Xilinx AXI Video Direct Memory Access Engine driver support
From: Shevchenko, Andriy <hidden>
Date: 2014-01-23 13:38:45
Also in:
linux-devicetree, lkml
On Thu, 2014-01-23 at 12:25 +0100, Lars-Peter Clausen wrote:
On 01/22/2014 05:52 PM, Srikanth Thokala wrote:
[...]
quoted
+ /* Request the interrupt */ + chan->irq = irq_of_parse_and_map(node, 0); + err = devm_request_irq(xdev->dev, chan->irq, xilinx_vdma_irq_handler, + IRQF_SHARED, "xilinx-vdma-controller", chan);This is a clasic example of where to not use devm_request_irq. 'chan' is accessed in the interrupt handler, but if you use devm_request_irq 'chan' will be freed before the interrupt handler has been released, which means there is now a race condition where the interrupt handler can access already freed memory.
Could you elaborate this case? As far as I understood managed resources are a kind of stack pile. In this case you have no such condition. Where am I wrong? -- Andy Shevchenko [off-list ref] Intel Finland Oy --------------------------------------------------------------------- Intel Finland Oy Registered Address: PL 281, 00181 Helsinki Business Identity Code: 0357606 - 4 Domiciled in Helsinki This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.