Libre RISC-V Mailing list Archives (accessible via public-inbox)
 help / color / Atom feed
From: bugzilla-daemon@libre-riscv.org
To: libre-riscv-dev@lists.libre-riscv.org
Subject: [libre-riscv-dev] [Bug 264] ISA switch needs to be a privileged operation
Date: Mon, 23 Mar 2020 10:24:15 +0000
Message-ID: <bug-264-13-8VKt4UTLtM@http.bugs.libre-riscv.org/> (raw)
In-Reply-To: <bug-264-13@http.bugs.libre-riscv.org/>

http://bugs.libre-riscv.org/show_bug.cgi?id=264

--- Comment #10 from Luke Kenneth Casson Leighton <lkcl@lkcl.net> ---
(In reply to cand from comment #7)
> Storing state sounds dangerous, consider someone jumping into the middle of
> compressed instrs.

this is precisely what a context-switch has to be able to do, because a trap
may occur in the middle of a pair of C instrs.

i very carefully designed VBLOCK around precisely this principle, involving
state information that is required to be context-switched.

and yes, if an end-user writes code that jumps into the middle of a block
without respecting the specification, they're on their own.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
_______________________________________________
libre-riscv-dev mailing list
libre-riscv-dev@lists.libre-riscv.org
http://lists.libre-riscv.org/mailman/listinfo/libre-riscv-dev

  parent reply index

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-22 23:19 [libre-riscv-dev] [Bug 264] New: " bugzilla-daemon
2020-03-23  0:01 ` [libre-riscv-dev] [Bug 264] " bugzilla-daemon
2020-03-23  0:26 ` bugzilla-daemon
2020-03-23  1:12 ` bugzilla-daemon
2020-03-23  7:54 ` bugzilla-daemon
2020-03-23  8:30 ` bugzilla-daemon
2020-03-23  8:37 ` bugzilla-daemon
2020-03-23  8:47 ` bugzilla-daemon
2020-03-23  8:54 ` bugzilla-daemon
2020-03-23  8:57 ` bugzilla-daemon
2020-03-23 10:24 ` bugzilla-daemon [this message]
2020-03-23 10:28 ` bugzilla-daemon

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=bug-264-13-8VKt4UTLtM@http.bugs.libre-riscv.org/ \
    --to=bugzilla-daemon@libre-riscv.org \
    --cc=libre-riscv-dev@lists.libre-riscv.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

Libre RISC-V Mailing list Archives (accessible via public-inbox)

Archives are clonable: git clone --mirror https://inbox.libre-soc.org/libre-riscv-dev

Example config snippet for mirrors


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git