linux-kernel - Re: [PATCH 3/4] HWPOISON: Report correct address granuality for AO huge page errors

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: <20101007084101.GE9891@spritzera.linux.bs1.fc.nec.co.jp>
Date:	Thu, 7 Oct 2010 17:41:01 +0900
From:	Naoya Horiguchi <n-horiguchi@...jp.nec.com>
To:	Andi Kleen <andi@...stfloor.org>
Cc:	linux-kernel@...r.kernel.org, fengguang.wu@...el.com,
	linux-mm@...ck.org, Andi Kleen <ak@...ux.intel.com>
Subject: Re: [PATCH 3/4] HWPOISON: Report correct address granuality for AO
 huge page errors

On Thu, Oct 07, 2010 at 09:38:48AM +0200, Andi Kleen wrote:
> On Thu, Oct 07, 2010 at 09:31:20AM +0900, Naoya Horiguchi wrote:
> > > @@ -198,7 +199,8 @@ static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
> > >  #ifdef __ARCH_SI_TRAPNO
> > >  	si.si_trapno = trapno;
> > >  #endif
> > > -	si.si_addr_lsb = PAGE_SHIFT;
> > > +	order = PageCompound(page) ? huge_page_order(page) : PAGE_SHIFT;
> >                                                      ^^^^
> >                                      huge_page_order(page_hstate(page)) ?
> 
> Ok.

order seems to represent a least significant bit of corrupted address,
so is huge_page_order() + PAGE_SHIFT or huge_page_shift() correct?
And since @page can be a tail page, compound_head() is needed as Wu-san pointed out.
So huge_page_shift(page_hstate(compound_head(page))) looks good for me.

Thanks,
Naoya Horiguchi
--
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/