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Re: [PATCH 0/3] Kill off show_stack() NULL-implies-current idiom

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On Mon, Sep 26, 2016 at 04:16:16PM +0100, Mark Rutland wrote:
> Today, show_stack() accepts a NULL task parameter, which it takes to mean the
> current task. However, as noted in tip/x86/asm commit:
> 
>   81539169f283329f ("x86/dumpstack: Remove NULL task pointer convention")
> 
> ... having a NULL task parameter imply current leads to subtle bugs in stack
> walking code (so far seen on both 86 and arm64), makes callsites harder to
> read, and is unnecessary as all callers have access to current.
> 
> As a step towards removing the problematic NULL-implies-current idiom entirely,
> these patches ensure that generic code explictly passes current to
> show_stack(), rather than relying on arch code to handle NULL.

This is a good step, though it would be really nice to fix this
tree-wide.  Do you have any plans to do so?

Regardless, for the series:

Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>

-- 
Josh

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[PATCH 0/3] Kill off show_stack() NULL-implies-current idiom Mark Rutland <mark.rutland@arm.com> - 2016-09-26 17:20 +0200
  Re: [PATCH 0/3] Kill off show_stack() NULL-implies-current idiom Josh Poimboeuf <jpoimboe@redhat.com> - 2016-09-26 22:10 +0200
    Re: [PATCH 0/3] Kill off show_stack() NULL-implies-current idiom Mark Rutland <mark.rutland@arm.com> - 2016-09-26 23:40 +0200
    Re: [PATCH 0/3] Kill off show_stack() NULL-implies-current idiom Mark Rutland <mark.rutland@arm.com> - 2016-09-27 20:00 +0200

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