From: Bruce Merry <1909823@bugs.launchpad.net>
To: qemu-devel@nongnu.org
Subject: [Bug 1909823] Re: RDPMC check on PCE is backwards
Date: Sat, 15 May 2021 08:32:34 -0000 [thread overview]
Message-ID: <162106755455.21294.520192923040014537.malone@soybean.canonical.com> (raw)
In-Reply-To: 160952341194.5646.9883047582696050309.malonedeb@chaenomeles.canonical.com
It looks like this was fixed in c45b426.
** Changed in: qemu
Status: Incomplete => Fix Released
--
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1909823
Title:
RDPMC check on PCE is backwards
Status in QEMU:
Fix Released
Bug description:
At [this
line](https://github.com/qemu/qemu/blob/75ee62ac606bfc9eb59310b9446df3434bf6e8c2/target/i386/tcg/misc_helper.c#L225)
the check on CR4_PCE_MASK is backwards: it's raising an exception if
the flag is set (and CPL != 0) rather than if the flag is clear.
It's low priority at the moment because the instruction isn't
implemented, so you get an illegal opcode exception when expecting a
GPF, or vice versa, but it's a time bomb for if it is ever
implemented.
The Intel docs also indicate that CR0.PE influences the protection; I
don't know if that's already reflected in env->hflags & HF_CPL_MASK.
To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1909823/+subscriptions
prev parent reply other threads:[~2021-05-15 8:43 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-01 17:50 [Bug 1909823] [NEW] RDPMC check on PCE is backwards Bruce Merry
2021-05-12 11:27 ` [Bug 1909823] " Thomas Huth
2021-05-15 8:32 ` Bruce Merry [this message]
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=162106755455.21294.520192923040014537.malone@soybean.canonical.com \
--to=1909823@bugs.launchpad.net \
--cc=qemu-devel@nongnu.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).