From: Catalin Marinas <catalin.marinas@arm.com>
To: Laura Abbott <labbott@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Mark Rutland <mark.rutland@arm.com>,
Will Deacon <will.deacon@arm.com>,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCHv5] arm64: Handle el1 synchronous instruction aborts cleanly
Date: Fri, 12 Aug 2016 18:05:09 +0100 [thread overview]
Message-ID: <20160812170508.GI12939@e104818-lin.cambridge.arm.com> (raw)
In-Reply-To: <1470792326-565-1-git-send-email-labbott@redhat.com>
On Tue, Aug 09, 2016 at 06:25:26PM -0700, Laura Abbott wrote:
> Executing from a non-executable area gives an ugly message:
>
> lkdtm: Performing direct entry EXEC_RODATA
> lkdtm: attempting ok execution at ffff0000084c0e08
> lkdtm: attempting bad execution at ffff000008880700
> Bad mode in Synchronous Abort handler detected on CPU2, code 0x8400000e -- IABT (current EL)
> CPU: 2 PID: 998 Comm: sh Not tainted 4.7.0-rc2+ #13
> Hardware name: linux,dummy-virt (DT)
> task: ffff800077e35780 ti: ffff800077970000 task.ti: ffff800077970000
> PC is at lkdtm_rodata_do_nothing+0x0/0x8
> LR is at execute_location+0x74/0x88
>
> The 'IABT (current EL)' indicates the error but it's a bit cryptic
> without knowledge of the ARM ARM. There is also no indication of the
> specific address which triggered the fault. The increase in kernel
> page permissions makes hitting this case more likely as well.
> Handling the case in the vectors gives a much more familiar looking
> error message:
>
> lkdtm: Performing direct entry EXEC_RODATA
> lkdtm: attempting ok execution at ffff0000084c0840
> lkdtm: attempting bad execution at ffff000008880680
> Unable to handle kernel paging request at virtual address ffff000008880680
> pgd = ffff8000089b2000
> [ffff000008880680] *pgd=00000000489b4003, *pud=0000000048904003, *pmd=0000000000000000
> Internal error: Oops: 8400000e [#1] PREEMPT SMP
> Modules linked in:
> CPU: 1 PID: 997 Comm: sh Not tainted 4.7.0-rc1+ #24
> Hardware name: linux,dummy-virt (DT)
> task: ffff800077f9f080 ti: ffff800008a1c000 task.ti: ffff800008a1c000
> PC is at lkdtm_rodata_do_nothing+0x0/0x8
> LR is at execute_location+0x74/0x88
>
> Acked-by: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
Applied. Thanks.
--
Catalin
next prev parent reply other threads:[~2016-08-12 17:05 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-10 1:25 Laura Abbott
2016-08-12 17:05 ` Catalin Marinas [this message]
2016-08-12 17:10 ` Catalin Marinas
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160812170508.GI12939@e104818-lin.cambridge.arm.com \
--to=catalin.marinas@arm.com \
--cc=ard.biesheuvel@linaro.org \
--cc=labbott@redhat.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®