Messages in this thread | | | Date | Wed, 21 Sep 2016 11:31:47 +0100 | From | Mark Rutland <> | Subject | Re: [RFC PATCH 0/8] arm64: move thread_info off of the task stack |
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On Tue, Sep 20, 2016 at 06:26:54PM -0700, Laura Abbott wrote: > On 09/15/2016 06:49 AM, Mark Rutland wrote: > >Building atop of Andy's work on x86 and generic code, these patches move > >arm64's thread_info off of the stack and into task_struct. This protects > >thread_info from corruption in the face of stack overflow, and serves as > >a step towards fully robust stack overflow handling will be addressed by > >subsequent patches. > > > >In contrast to x86, we can't place some critical data such as > >preempt_count in percpu variables, and we must store these in some > >per-task location. This, compounded with the way headers are organised > >conspires to require us to still define our own thread_info. I > >understand that the longer term plan is to kill off thread_info > >entirely, hence I'm sending this as an RFC so we can figure out if/how > >we can achieve that. > > > >These patches are based on Andy's x86/vmap_stack branch [1,2], and I've > >pushed a copy to me arm64/ti-stack-split branch [3,4]. The result of > >these patches boots happily on platforms within reach of my desk, but > >has not seen much stressing so far. > > FWIW, I used your ti-stack-split branch while running some kernel builds > and it seems to work well enough. You can take that as a Tested-by or I > can re-test with a non-RFC version.
Thanks for testing, and many thanks for the offer!
Based on Andy's feedback some core bits are changing, and I'm hoping to have a non-RFC version out soon once I've fixed up the remaining fallout. I'll make sure you're Cc'd!
Thanks, Mark.
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