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Date:   Thu, 19 May 2022 22:15:27 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     David Laight <David.Laight@aculab.com>
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        "andriy.shevchenko@linux.intel.com" 
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Subject: Re: [PATCH v2 03/28] vsprintf: %pf(%p)
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On Thu, May 19, 2022 at 09:06:24PM +0000, David Laight wrote:
> I suspect this a very good way to blow the kernel stack.
> The highest stack use is already very likely to be inside
> the printf code in an error path somewhere.

...

> Double copying using a temporary buffer isn't the end of the world.

How can you hold both of these positions simultaneously?