linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: "Christopher M. Riedl" <cmr@codefail.de>
Cc: peterz@infradead.org, linuxppc-dev@lists.ozlabs.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/8] powerpc: Mark functions called inside uaccess blocks w/ 'notrace'
Date: Fri, 16 Oct 2020 07:56:16 +0100	[thread overview]
Message-ID: <20201016065616.GB9343@infradead.org> (raw)
In-Reply-To: <20201015150159.28933-4-cmr@codefail.de>

On Thu, Oct 15, 2020 at 10:01:54AM -0500, Christopher M. Riedl wrote:
> Functions called between user_*_access_begin() and user_*_access_end()
> should be either inlined or marked 'notrace' to prevent leaving
> userspace access exposed. Mark any such functions relevant to signal
> handling so that subsequent patches can call them inside uaccess blocks.

I don't think running this much code with uaccess enabled is a good
idea.  Please refactor the code to reduce the criticial sections with
uaccess enabled.

Btw, does powerpc already have the objtool validation that we don't
accidentally jump out of unsafe uaccess critical sections?

  reply	other threads:[~2020-10-16  6:58 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-15 15:01 [PATCH 0/8] Improve signal performance on PPC64 with KUAP Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 1/8] powerpc/uaccess: Add unsafe_copy_from_user Christopher M. Riedl
2020-10-16  6:54   ` Christoph Hellwig
2020-10-16 13:18     ` Christophe Leroy
2020-10-16 13:17   ` Christophe Leroy
2020-10-20  3:00     ` Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx,fpr}_from_user() Christopher M. Riedl
2020-10-16 13:48   ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user() Christophe Leroy
2020-10-20  2:01     ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx,fpr}_from_user() Christopher M. Riedl
2021-02-06 16:32       ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user() Christophe Leroy
2021-02-06 17:39         ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx,fpr}_from_user() Christopher M. Riedl
2021-02-07 10:12           ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user() Christophe Leroy
2021-02-08 17:14             ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx,fpr}_from_user() Christopher M. Riedl
2021-02-08 17:18               ` [PATCH 2/8] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user() Christophe Leroy
2020-10-15 15:01 ` [PATCH 3/8] powerpc: Mark functions called inside uaccess blocks w/ 'notrace' Christopher M. Riedl
2020-10-16  6:56   ` Christoph Hellwig [this message]
2020-10-16  9:41     ` Peter Zijlstra
2020-10-20  7:34       ` Michael Ellerman
2020-10-16  7:02   ` Christophe Leroy
2020-10-20  1:59     ` Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 4/8] powerpc/signal64: Replace setup_sigcontext() w/ unsafe_setup_sigcontext() Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 5/8] powerpc/signal64: Replace restore_sigcontext() w/ unsafe_restore_sigcontext() Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 6/8] powerpc/signal64: Replace setup_trampoline() w/ unsafe_setup_trampoline() Christopher M. Riedl
2020-10-16 13:56   ` Christophe Leroy
2020-10-20  2:42     ` Christopher M. Riedl
2020-10-20  5:02       ` Christophe Leroy
2020-10-15 15:01 ` [PATCH 7/8] powerpc/signal64: Rewrite handle_rt_signal64() to minimise uaccess switches Christopher M. Riedl
2020-10-16 14:00   ` Christophe Leroy
2020-10-20  2:44     ` Christopher M. Riedl
2020-10-15 15:01 ` [PATCH 8/8] powerpc/signal64: Rewrite rt_sigreturn() " Christopher M. Riedl
2020-10-16 14:07   ` Christophe Leroy
2020-10-20  2:45     ` Christopher M. Riedl

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=20201016065616.GB9343@infradead.org \
    --to=hch@infradead.org \
    --cc=cmr@codefail.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=peterz@infradead.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).