qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Richard Henderson <richard.henderson@linaro.org>
To: "Michael Clark" <mjc@sifive.com>,
	"Philippe Mathieu-Daudé" <f4bug@amsat.org>
Cc: "QEMU Developers" <qemu-devel@nongnu.org>,
	"Alex Bennée" <alex.bennee@linaro.org>,
	"Peter Maydell" <peter.maydell@linaro.org>,
	"Sagar Karandikar" <sagark@eecs.berkeley.edu>,
	"Bastian Koppelmann" <kbastian@mail.uni-paderborn.de>,
	"Palmer Dabbelt" <palmer@sifive.com>,
	"RISC-V Patches" <patches@groups.riscv.org>
Subject: Re: [Qemu-devel] [PATCH v1 1/1] RISC-V: Workaround for critical mstatus.FS MTTCG bug
Date: Wed, 28 Mar 2018 10:26:30 +0800	[thread overview]
Message-ID: <2bb7c25b-237b-4225-319c-90f14f3c560d@linaro.org> (raw)
In-Reply-To: <CAHNT7Nt40C8Bh3VJHjv8f+obSbU6Ki8ThXH2L7o4zoSM2LnK5A@mail.gmail.com>

On 03/28/2018 08:15 AM, Michael Clark wrote:
> On looking at this again, I think we may need to remove
> the qemu_tcg_mttcg_enabled conditional and always return dirty if the state is
> initial or clean, but not off.

Yes.

> While testing on uniprocessor worked okay, it's likely because we were lucky
> and there was no task migration or multiple FPU tasks working.

Also yes.

>     > +        if (qemu_tcg_mttcg_enabled()) {
>     > +            /* FP is always dirty or off */
>     > +            if (mstatus & MSTATUS_FS) {
>     > +                mstatus |= MSTATUS_FS;
>     > +            }
>     > +        }

I've just posted an alternate patch set to track MSTATUS_FS more exactly, but
if that's thought to be too much this late in the cycle, then I'll sign off on
this patch without the mttcg test.


r~

  reply	other threads:[~2018-03-28  2:26 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-27 19:54 [Qemu-devel] [PATCH v1 0/1] RISC-V: Critical fixes for QEMU 2.12 Michael Clark
2018-03-27 19:54 ` [Qemu-devel] [PATCH v1 1/1] RISC-V: Workaround for critical mstatus.FS MTTCG bug Michael Clark
2018-03-27 22:17   ` Philippe Mathieu-Daudé
2018-03-28  0:15     ` Michael Clark
2018-03-28  2:26       ` Richard Henderson [this message]
2018-03-30  7:11       ` Alex Bennée
2018-03-30 17:01         ` Michael Clark
2018-03-28  2:08   ` [Qemu-devel] [patches] " Palmer Dabbelt

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=2bb7c25b-237b-4225-319c-90f14f3c560d@linaro.org \
    --to=richard.henderson@linaro.org \
    --cc=alex.bennee@linaro.org \
    --cc=f4bug@amsat.org \
    --cc=kbastian@mail.uni-paderborn.de \
    --cc=mjc@sifive.com \
    --cc=palmer@sifive.com \
    --cc=patches@groups.riscv.org \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.org \
    --cc=sagark@eecs.berkeley.edu \
    /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).