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Date:   Fri, 17 Sep 2021 12:21:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     =?utf-8?B?546L6LSH?= <yun.wang@linux.alibaba.com>
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        Arnaldo Carvalho de Melo <acme@kernel.org>,
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Subject: Re: [PATCH] x86/dumpstack/64: Add guard pages to stack_info
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On Fri, Sep 17, 2021 at 11:02:07AM +0800, 王贇 wrote:
> 
> 
> On 2021/9/16 下午6:02, Peter Zijlstra wrote:
> [snip]
> >  
> > +static __always_inline bool in_stack_guard(void *addr, void *begin, void *end)
> > +{
> > +#ifdef CONFIG_VMAP_STACK
> > +	if (addr > (begin - PAGE_SIZE))
> > +		return true;
> 
> After fix this logical as:
> 
>   addr >= (begin - PAGE_SIZE) && addr < begin
> 
> it's working.

Shees, I seem to have a knack for getting it wrong, don't I. Thanks!

Anyway, I'll ammend the commit locally, but I'd really like some
feedback from Andy, who wrote all that VIRT_STACK stuff in the first
place.