linux-kernel - Re: PROBLEM: ARM-dma-mapping-fix-for-speculative-prefetching cause OOPS

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: <BANLkTimo18w5yuE4jtATPvbgENCL04LMpA@mail.gmail.com>
Date:	Thu, 30 Jun 2011 11:02:54 -0700
From:	Dan Williams <dan.j.williams@...el.com>
To:	Qin Dehua <qindehua@...il.com>
Cc:	Russell King <rmk@....linux.org.uk>, linux-kernel@...r.kernel.org,
	santosh.shilimkar@...com, neilb@...e.de
Subject: Re: PROBLEM: ARM-dma-mapping-fix-for-speculative-prefetching cause OOPS

On Thu, Jun 30, 2011 at 4:28 AM, Russell King <rmk@....linux.org.uk> wrote:
> On Thu, Jun 30, 2011 at 07:16:24PM +0800, Qin Dehua wrote:
>> Commit 2ffe2da3e follows v2.6.32, the message is from kernel build on
>> commit 2ffe2da3e.
>>
>> The config has CONFIG_BUG=y and CONFIG_DEBUG_BUGVERBOSE=y, but the
>> message is Oops, not BUG() macro, so they don't have line number.
>
> In that case, the raid5 code contains an explicit NULL pointer
> dereference which isn't a BUG() - the code line disassembles to:
>
>   0:   ebfff1bc        bl      0xffffc6f8
>   4:   e28dd044        add     sp, sp, #68     ; 0x44
>   8:   e8bd8ff0        pop     {r4, r5, r6, r7, r8, r9, sl, fp, pc}
>   c:   e3a03000        mov     r3, #0  ; 0x0
>  10:   e5833000        str     r3, [r3] <=== faulting instruction
>
> So, if you're saying that's not a BUG(), then I don't know what it is
> and I'm afraid I can't help because the oops doesn't make any sense
> to me.
>

QinDehua,

Can you rebuild with CONFIG_DEBUG_INFO=y, reproduce the crash and then
send the output of:

$ gdb drivers/md/raid5.o
(gdb) li *(raid5d+0x580)
(gdb) li *(__release_stripe+0x1e4)
etc...

...those offsets might change so just grab whatever "PC is at "
reports in the oops.

--
Dan
--
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/