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Date: Thu, 5 Oct 2017 08:55:26 -0500
From: Bjorn Helgaas <>
To: Linus Torvalds <>
Cc: "Roberts, William C" <>, Tejun Heo <>, 
	Jordan Glover <>, "Tobin C. Harding" <>, 
	Greg KH <>, Petr Mladek <>, 
	Joe Perches <>, Ian Campbell <>, 
	Sergey Senozhatsky <>, 
	"" <>, 
	Catalin Marinas <>, Will Deacon <>, 
	Steven Rostedt <>, Chris Fries <>, 
	Dave Weinstein <>
Subject: Re: [RFC V2 0/6] add more kernel pointer filter options

On Wed, Oct 4, 2017 at 7:09 PM, Linus Torvalds
<> wrote:
> On Wed, Oct 4, 2017 at 4:52 PM, Linus Torvalds
> <> wrote:
>> It also shows
>>     software IO TLB [mem PA-PB] (64MB) mapped at [VA-VB]
>> for example.  And THIS IS IMPORTANT! The physical address is shown
>> with "%#010llx".
> Oh, and I added Tejun for the percpu printout, but didn't add Bjorn
> for this one.
> Like the percpu one, I suspect that this pr_info() isn't really
> important enough to stay, and while it doesn't sound nearly as
> interesting as the percpu virtual address to an attacker, it probably
> isn't important enough to leak kernel (and hardware) data for.
> Bjorn?

My only interest in the "software IO TLB" message was to make the
style match other similar things; I personally don't care whether this
message exists at all.

I haven't seen the whole series, but I do hope %pR remains useful.  We
use it often to analyze PCI BAR assignment issues.


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