Messages in this thread | | | Date | Wed, 15 Jan 2020 15:33:47 +0100 | From | Peter Zijlstra <> | Subject | Re: RFC: hold i_rwsem until aio completes |
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On Wed, Jan 15, 2020 at 09:24:28AM -0400, Jason Gunthorpe wrote:
> I was interested because you are talking about allowing the read/write side > of a rw sem to be held across a return to user space/etc, which is the > same basic problem.
No it is not; allowing the lock to be held across userspace doesn't change the owner. This is a crucial difference, PI depends on there being a distinct owner. That said, allowing the lock to be held across userspace still breaks PI in that it completely wrecks the ability to analyze the critical section.
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