linux-kernel - RE: Question about output of kmalloc()

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Date:   Tue, 14 Jan 2020 10:36:55 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     'xuesong Chen' <xuesong1977@...il.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: Question about output of kmalloc()

From:  xuesong Chen
> Sent: 14 January 2020 07:21
> Below code snippet in the .ko:
> 
> unsigned long *p = (unsigned long *)kmalloc(sizeof(*p), GFP_KERNEL);
> printk("Addr of p = 0x%p\n", p);
> 
> The output is:
> Addr of p = 0x0000000018606ce7
> 
> In my mind, during the early day, the p should be 0xfffff...., can
> anybody give some tips why the output looks like it's a physical
> address?

The printed value is hashed to avoid leaking info.

	David

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