linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>
To: Josh Poimboeuf <jpoimboe@redhat.com>, Mark Brown <broonie@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Julien Thierry <jthierry@redhat.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Miroslav Benes <mbenes@suse.cz>, Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC PATCH 0/3] arm64: Implement reliable stack trace
Date: Sun, 31 Jan 2021 21:20:07 -0600	[thread overview]
Message-ID: <30d538ab-2ffe-6df9-5217-62944b90806d@linux.microsoft.com> (raw)
In-Reply-To: <4a934966-0460-459c-cce3-ca67f099d781@linux.microsoft.com>



On 1/29/21 3:39 PM, Madhavan T. Venkataraman wrote:
> - A separate register has to be reserved for holding the shadow stack
>   pointer. The compiler (gcc) has to be changed to not use this register for
>   other purposes. And we have to trust that there are no compiler bugs
>   in this area. All assembly code that currently uses this register for
>   anything needs to be reviewed and potentially changed. This includes
>   all inline assembly code. BTW, I believe clang uses x18 for the shadow
>   stack pointer register.

Actually, if the stack and the shadow stack are allocated so that they are
adjacent or at a fixed distance from each other, we don't need a separate
register. We can compute parallel stack addresses from stack addresses by
a simple calculation.

So, this is not an issue.

Madhavan

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2021-02-01  3:21 UTC|newest]

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-12 17:26 [RFC PATCH 0/3] arm64: Implement reliable stack trace Mark Brown
2020-10-12 17:26 ` [RFC PATCH 1/3] arm64: remove EL0 exception frame record Mark Brown
2020-10-12 17:26 ` [RFC PATCH 2/3] arm64: stacktrace: Report when we reach the end of the stack Mark Brown
2020-10-13 11:07   ` Mark Rutland
2020-10-12 17:26 ` [RFC PATCH 3/3] arm64: stacktrace: Implement reliable stacktrace Mark Brown
2020-10-13 10:42   ` Mark Brown
2020-10-13 11:42   ` Mark Rutland
2020-10-13 16:12     ` Mark Brown
2020-10-15 13:33   ` Miroslav Benes
2020-10-15 15:57     ` Mark Brown
2020-10-16 10:13       ` Miroslav Benes
2020-10-16 12:30         ` Mark Brown
2020-10-15 13:39 ` [RFC PATCH 0/3] arm64: Implement reliable stack trace Miroslav Benes
2020-10-15 14:16   ` Mark Rutland
2020-10-15 15:49     ` Mark Brown
2020-10-15 21:29       ` Josh Poimboeuf
2020-10-16 11:14         ` Mark Rutland
2020-10-20 10:03           ` Mark Rutland
2020-10-20 15:58             ` Josh Poimboeuf
2020-10-16 12:15         ` Mark Brown
2020-10-19 23:41           ` Josh Poimboeuf
2020-10-20 15:39             ` Mark Brown
2020-10-20 16:28               ` Josh Poimboeuf
2021-01-27 14:02 ` Madhavan T. Venkataraman
2021-01-27 16:40   ` Mark Rutland
2021-01-27 17:11     ` Mark Brown
2021-01-27 17:24   ` Madhavan T. Venkataraman
2021-01-27 19:54 ` Madhavan T. Venkataraman
2021-01-28 14:22   ` Mark Brown
2021-01-28 15:26     ` Josh Poimboeuf
2021-01-29 21:39       ` Madhavan T. Venkataraman
2021-02-01  3:20         ` Madhavan T. Venkataraman [this message]
2021-02-01 14:39         ` Mark Brown
2021-01-30  4:38       ` Madhavan T. Venkataraman
2021-02-01 15:21       ` Madhavan T. Venkataraman
2021-02-01 15:46         ` Madhavan T. Venkataraman
2021-02-01 16:02         ` Mark Rutland
2021-02-01 16:22           ` Mark Brown
2021-02-01 21:40             ` Madhavan T. Venkataraman
2021-02-01 21:38           ` Madhavan T. Venkataraman
2021-02-01 23:00             ` Josh Poimboeuf
2021-02-02  2:29               ` Madhavan T. Venkataraman
2021-02-02  3:36                 ` Josh Poimboeuf
2021-02-02 10:05             ` Mark Rutland
2021-02-02 13:33               ` Madhavan T. Venkataraman
2021-02-02 13:35               ` Madhavan T. Venkataraman
2021-02-02 23:32               ` Madhavan T. Venkataraman
2021-02-03 16:53                 ` Mark Rutland
2021-02-03 19:03                   ` Madhavan T. Venkataraman
2021-02-05  2:36                     ` Madhavan T. Venkataraman
2021-02-01 21:59     ` Madhavan T. Venkataraman
2021-02-02 13:36       ` Mark Brown

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=30d538ab-2ffe-6df9-5217-62944b90806d@linux.microsoft.com \
    --to=madvenka@linux.microsoft.com \
    --cc=broonie@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=jpoimboe@redhat.com \
    --cc=jthierry@redhat.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=mark.rutland@arm.com \
    --cc=mbenes@suse.cz \
    --cc=will@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 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).