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Date:   Thu, 21 Feb 2019 16:37:26 +0900
From:   Masami Hiramatsu <mhiramat@kernel.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>,
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        Jann Horn <jannh@google.com>,
        Kees Cook <keescook@chromium.org>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH 1/2 v2] kprobe: Do not use uaccess functions to access
 kernel memory that can fault
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On Wed, 20 Feb 2019 11:42:17 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Thu, 21 Feb 2019 01:04:53 +0900
> Masami Hiramatsu <mhiramat@kernel.org> wrote:
> 
> > > What about just adding 'u' to the end of the offset? Say you have a
> > > data structure in kernel space that has a field in user space you want
> > > to reference?
> > > 
> > > 
> > > 	field_val=+8u(+0(%si))  
> > 
> > Ah, that looks good :~) thank you for this idea!
> 
> <bike-shed>
> 
> Hmm, I wonder if we should make it +u8 or u+8? as +8u may be confused
> as unsigned? Like 8ULL. I don't know. Kernel developers suck at
> naming :-p

I like +u8 since it is easier to implement :-p.

Thank you,

> 
> </bike-shed>
> 
> -- Steve


-- 
Masami Hiramatsu <mhiramat@kernel.org>