linux-kernel - Re: [PATCH 7/8] percpu: add __percpu sparse annotations to hw

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100126023238.GC19799@ZenIV.linux.org.uk>
Date:	Tue, 26 Jan 2010 02:32:38 +0000
From:	Al Viro <viro@...IV.linux.org.uk>
To:	Tejun Heo <tj@...nel.org>
Cc:	"H. Peter Anvin" <hpa@...or.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	linux-kernel@...r.kernel.org, axboe@...nel.dk,
	rusty@...tcorp.com.au, akpm@...ux-foundation.org,
	ebiederm@...ssion.com, tytso@....edu, Trond.Myklebust@...app.com,
	aelder@....com, hch@...radead.org, davem@...emloft.net,
	netdev@...r.kernel.org, x86@...nel.org, mingo@...hat.com,
	dan.j.williams@...el.com, borislav.petkov@....com,
	ying.huang@...el.com, lenb@...nel.org, neilb@...e.de,
	cl@...ux-foundation.org
Subject: Re: [PATCH 7/8] percpu: add __percpu sparse annotations to
	hw_breakpoint

On Tue, Jan 26, 2010 at 11:16:42AM +0900, Tejun Heo wrote:

> # define RELOC_HIDE(ptr, off)					\
>   ({ unsigned long __ptr;					\
>      __ptr = (unsigned long) (ptr);				\
>     (typeof(ptr)) (__ptr + (off)); })
> 
> #define __verify_pcpu_ptr(ptr)	do {					\
> 	const void __percpu *__vpp_verify = (typeof(ptr))NULL;		\
> 	(void)__vpp_verify;						\
> } while (0)
> 
> /* Weird cast keeps both GCC and sparse happy. */
> #define SHIFT_PERCPU_PTR(__p, __offset)	({				\
> 	__verify_pcpu_ptr((__p));					\
> 	RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)); \
> })
> 
> #define per_cpu(var, cpu) \
> 	(*SHIFT_PERCPU_PTR(&(var), per_cpu_offset(cpu)))

Eh...  You are leaving that noderef in place in case of array.  And _that_
is not an address space, so casts to AS 0 won't do you any good.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/