From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: linux-kernel@vger.kernel.org
Cc: x86@kernel.org, "Andy Lutomirski" <luto@kernel.org>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Radim Krčmář" <rkrcmar@redhat.com>,
kvm@vger.kernel.org, "Jason A. Donenfeld" <Jason@zx2c4.com>,
"Rik van Riel" <riel@surriel.com>,
"Sebastian Andrzej Siewior" <bigeasy@linutronix.de>
Subject: [RFC PATCH 08/10] x86/fpu: prepare copy_fpstate_to_sigframe for TIF_LOAD_FPU
Date: Wed, 12 Sep 2018 15:33:51 +0200 [thread overview]
Message-ID: <20180912133353.20595-9-bigeasy@linutronix.de> (raw)
In-Reply-To: <20180912133353.20595-1-bigeasy@linutronix.de>
From: Rik van Riel <riel@surriel.com>
If TIF_LOAD_FPU is set, then the registers are saved (not loaded). In that case
we skip the saving part.
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
arch/x86/kernel/fpu/signal.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index ff6e7a67522d8..906efd9572ffa 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -155,13 +155,17 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
sizeof(struct user_i387_ia32_struct), NULL,
(struct _fpstate_32 __user *) buf) ? -1 : 1;
- /* Update the thread's fxstate to save the fsave header. */
- if (ia32_fxstate)
- copy_fxregs_to_kernel(fpu);
- else {
- copy_fpregs_to_fpstate(fpu);
- fpregs_deactivate(fpu);
+ __fpregs_changes_begin();
+ if (!test_thread_flag(TIF_LOAD_FPU)) {
+ /* Update the thread's fxstate to save the fsave header. */
+ if (ia32_fxstate)
+ copy_fxregs_to_kernel(fpu);
+ else {
+ copy_fpregs_to_fpstate(fpu);
+ fpregs_deactivate(fpu);
+ }
}
+ __fpregs_changes_end();
if (using_compacted_format()) {
copy_xstate_to_user(buf_fx, xsave, 0, size);
--
2.19.0
next prev parent reply other threads:[~2018-09-12 13:36 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-12 13:33 [RFC PATCH] x86: load FPU registers on return to userland Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 01/10] x86/entry: remove _TIF_ALLWORK_MASK Sebastian Andrzej Siewior
2018-09-27 14:21 ` Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 02/10] kvm: x86: make kvm_{load|put}_guest_fpu() static Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 03/10] x86/fpu: add (__)make_fpregs_active helpers Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 04/10] x86/fpu: eager switch PKRU state Sebastian Andrzej Siewior
2018-09-12 14:18 ` Paolo Bonzini
2018-09-12 15:24 ` Andy Lutomirski
2018-09-12 15:30 ` Paolo Bonzini
2018-09-14 20:35 ` [RFC PATCH 04/10 v2 ] " Sebastian Andrzej Siewior
2018-09-17 8:37 ` Paolo Bonzini
2018-09-18 14:27 ` Sebastian Andrzej Siewior
2018-09-18 15:07 ` Paolo Bonzini
2018-09-18 15:11 ` Rik van Riel
2018-09-18 15:29 ` Paolo Bonzini
2018-09-18 16:04 ` Sebastian Andrzej Siewior
2018-09-18 17:29 ` Rik van Riel
2018-09-19 5:55 ` Paolo Bonzini
2018-09-19 16:57 ` Sebastian Andrzej Siewior
2018-09-19 17:00 ` Paolo Bonzini
2018-09-19 17:19 ` Sebastian Andrzej Siewior
2018-09-19 19:38 ` Rik van Riel
2018-09-19 19:49 ` Andy Lutomirski
2018-09-12 15:20 ` [RFC PATCH 04/10] " Andy Lutomirski
2018-09-12 15:30 ` Rik van Riel
2018-09-12 15:49 ` Andy Lutomirski
2018-09-19 16:58 ` Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 05/10] x86/pkeys: Drop the preempt-disable section Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 06/10] x86/fpu: Always store the registers in copy_fpstate_to_sigframe() Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 07/10] x86/entry: add TIF_LOAD_FPU Sebastian Andrzej Siewior
2018-09-12 13:33 ` Sebastian Andrzej Siewior [this message]
2018-09-12 13:33 ` [RFC PATCH 09/10] x86/fpu: copy non-resident FPU state at fork time Sebastian Andrzej Siewior
2018-09-12 13:33 ` [RFC PATCH 10/10] x86/fpu: defer FPU state load until return to userspace Sebastian Andrzej Siewior
2018-09-12 15:47 ` Andy Lutomirski
2018-09-19 17:05 ` Sebastian Andrzej Siewior
2018-09-21 3:45 ` Andy Lutomirski
2018-09-21 4:15 ` Andy Lutomirski
2018-09-26 11:12 ` Sebastian Andrzej Siewior
2018-09-26 14:34 ` Andy Lutomirski
2018-09-26 15:32 ` Sebastian Andrzej Siewior
2018-09-26 16:24 ` Andy Lutomirski
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=20180912133353.20595-9-bigeasy@linutronix.de \
--to=bigeasy@linutronix.de \
--cc=Jason@zx2c4.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=pbonzini@redhat.com \
--cc=riel@surriel.com \
--cc=rkrcmar@redhat.com \
--cc=x86@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).