All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@kernel.org>
To: Tony Luck <tony.luck@intel.com>, Borislav Petkov <bp@alien8.de>
Cc: linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH 1/3] x86, ras: Add new infrastructure for machine check fixup tables
Date: Wed, 11 Nov 2015 20:14:56 -0800	[thread overview]
Message-ID: <56441240.6000607@kernel.org> (raw)
In-Reply-To: <5bf6f812a7dd2b619487c57987e29b3884c6c4ec.1447093568.git.tony.luck@intel.com>

On 11/06/2015 12:57 PM, Tony Luck wrote:
> Copy the existing page fault fixup mechanisms to create a new table
> to be used when fixing machine checks. Note:
> 1) At this time we only provide a macro to annotate assembly code
> 2) We assume all fixups will in code builtin to the kernel.

Shouldn't the first step be to fixup failures during user memory access?

>
> Signed-off-by: Tony Luck <tony.luck@intel.com>
> ---
>   arch/x86/include/asm/asm.h        |  7 +++++++
>   arch/x86/include/asm/uaccess.h    |  1 +
>   arch/x86/mm/extable.c             | 16 ++++++++++++++++
>   include/asm-generic/vmlinux.lds.h |  6 ++++++
>   include/linux/module.h            |  1 +
>   kernel/extable.c                  | 14 ++++++++++++++
>   6 files changed, 45 insertions(+)
>
> diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
> index 189679aba703..f2fa7973f18f 100644
> --- a/arch/x86/include/asm/asm.h
> +++ b/arch/x86/include/asm/asm.h
> @@ -58,6 +58,13 @@
>   	.long (to) - . + 0x7ffffff0 ;				\
>   	.popsection
>
> +# define _ASM_MCEXTABLE(from, to)				\
> +	.pushsection "__mcex_table", "a" ;			\
> +	.balign 8 ;						\
> +	.long (from) - . ;					\
> +	.long (to) - . ;					\
> +	.popsection
> +

This does something really weird to rax.  (Also, what happens on 32-bit 
kernels?  There's no bit 63.)

Please at least document it clearly.

--Andy

  parent reply	other threads:[~2015-11-12  4:15 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-09 18:26 [RFC PATCH 0/3] Machine check recovery when kernel accesses poison Tony Luck
2015-11-06 20:57 ` [PATCH 1/3] x86, ras: Add new infrastructure for machine check fixup tables Tony Luck
2015-11-10 11:21   ` Borislav Petkov
2015-11-10 22:05     ` Luck, Tony
2015-11-12  4:14   ` Andy Lutomirski [this message]
2015-11-12 19:44     ` Luck, Tony
2015-11-12 20:04       ` Andy Lutomirski
2015-11-12 21:17         ` Luck, Tony
2015-11-06 21:01 ` [PATCH 2/3] x86, ras: Extend machine check recovery code to annotated ring0 areas Tony Luck
2015-11-10 11:21   ` Borislav Petkov
2015-11-10 22:11     ` Luck, Tony
2015-11-11 11:01       ` Borislav Petkov
2015-11-12  4:19   ` Andy Lutomirski
2015-11-12 19:55     ` Luck, Tony
2015-11-06 21:08 ` [PATCH 3/3] x86, ras: Add mcsafe_memcpy() function to recover from machine checks Tony Luck
2015-11-12  7:53   ` Ingo Molnar
2015-11-12 20:01     ` Luck, Tony
2015-11-27 10:16       ` Ingo Molnar
2015-12-08 21:30         ` Dan Williams
2015-12-08 22:08           ` Luck, Tony
2015-12-08 22:08             ` Luck, Tony
2015-12-14  9:55           ` Ingo Molnar
2015-11-09 18:48 ` [RFC PATCH 0/3] Machine check recovery when kernel accesses poison Tony Luck
2015-11-10 11:21 ` Borislav Petkov
2015-11-10 21:55   ` Luck, Tony
2015-11-11 20:41     ` Borislav Petkov
2015-11-11 21:48       ` Luck, Tony
2015-11-11 22:28         ` Borislav Petkov
2015-11-11 22:32           ` Luck, Tony

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=56441240.6000607@kernel.org \
    --to=luto@kernel.org \
    --cc=bp@alien8.de \
    --cc=linux-edac@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tony.luck@intel.com \
    --cc=x86@kernel.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.