From: Lai Jiangshan <jiangshanlai@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>,
ink@jurassic.park.msu.ru, mattst88@gmail.com, vgupta@kernel.org,
linux@armlinux.org.uk, ulli.kroll@googlemail.com,
linus.walleij@linaro.org, shawnguo@kernel.org,
Sascha Hauer <s.hauer@pengutronix.de>,
kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com,
tony@atomide.com, khilman@kernel.org, catalin.marinas@arm.com,
Will Deacon <will@kernel.org>,
guoren@kernel.org, bcain@quicinc.com,
Huacai Chen <chenhuacai@kernel.org>,
kernel@xen0n.name, geert@linux-m68k.org, sammy@sammy.net,
monstr@monstr.eu, tsbogend@alpha.franken.de, dinguyen@kernel.org,
jonas@southpole.se, stefan.kristiansson@saunalahti.fi,
shorne@gmail.com, James.Bottomley@hansenpartnership.com,
deller@gmx.de, Michael Ellerman <mpe@ellerman.id.au>,
benh@kernel.crashing.org, paulus@samba.org,
Paul Walmsley <paul.walmsley@sifive.com>,
Palmer Dabbelt <palmer@dabbelt.com>,
Albert Ou <aou@eecs.berkeley.edu>,
hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com,
borntraeger@linux.ibm.com, svens@linux.ibm.com,
ysato@users.sourceforge.jp, dalias@libc.org, davem@davemloft.net,
Richard Weinberger <richard@nod.at>,
anton.ivanov@cambridgegreys.com,
Johannes Berg <johannes@sipsolutions.net>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
acme <acme@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
jolsa@kernel.org, Namhyung Kim <namhyung@kernel.org>,
Juergen Gross <jgross@suse.com>,
srivatsa@csail.mit.edu, amakhalov@vmware.com,
VMware Inc <pv-drivers@vmware.com>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
chris@zankel.net, jcmvbkbc@gmail.com, rafael@kernel.org,
lenb@kernel.org, pavel@ucw.cz, gregkh@linuxfoundation.org,
mturquette@baylibre.com, sboyd@kernel.org,
daniel.lezcano@linaro.org, lpieralisi@kernel.org,
sudeep.holla@arm.com, agross@kernel.org,
bjorn.andersson@linaro.org, Anup Patel <anup@brainfault.org>,
thierry.reding@gmail.com, jonathanh@nvidia.com,
jacob.jun.pan@linux.intel.com, Arnd Bergmann <arnd@arndb.de>,
yury.norov@gmail.com,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com,
senozhatsky@chromium.org, john.ogness@linutronix.de,
paulmck@kernel.org, frederic@kernel.org,
quic_neeraju@quicinc.com, josh@joshtriplett.org,
mathieu.desnoyers@efficios.com, joel@joelfernandes.org,
juri.lelli@redhat.com, vincent.guittot@linaro.org,
dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de,
bristot@redhat.com, vschneid@redhat.com, jpoimboe@kernel.org,
linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-snps-arc@lists.infradead.org,
linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org,
linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org,
linux-mips@vger.kernel.org, openrisc@lists.librecores.org,
linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org,
linux-sh@vger.kernel.org, sparclinux@vger.kernel.org,
linux-um@lists.infradead.org, linux-perf-users@vger.kernel.org,
virtualization@lists.linux-foundation.org,
xen-devel@lists.xenproject.org, linux-xtensa@linux-xtensa.org,
linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org,
linux-clk@vger.kernel.org, linux-arm-msm@vger.kernel.org,
linux-tegra@vger.kernel.org, linux-arch@vger.kernel.org,
rcu@vger.kernel.org, Isaku Yamahata <isaku.yamahata@gmail.com>,
kirill.shutemov@linux.intel.com
Subject: Re: [PATCH 21/36] x86/tdx: Remove TDX_HCALL_ISSUE_STI
Date: Mon, 13 Jun 2022 16:26:01 +0800 [thread overview]
Message-ID: <CAJhGHyCnu_BsKf5STMMJKMWm0NVZ8qXT8Qh=BhhCjSSgwchL3Q@mail.gmail.com> (raw)
In-Reply-To: <20220608144517.251109029@infradead.org>
On Wed, Jun 8, 2022 at 10:48 PM Peter Zijlstra <peterz@infradead.org> wrote:
>
> Now that arch_cpu_idle() is expected to return with IRQs disabled,
> avoid the useless STI/CLI dance.
>
> Per the specs this is supposed to work, but nobody has yet relied up
> this behaviour so broken implementations are possible.
I'm totally newbie here.
The point of safe_halt() is that STI must be used and be used
directly before HLT to enable IRQ during the halting and stop
the halting if there is any IRQ.
In TDX case, STI must be used directly before the hypercall.
Otherwise, no IRQ can come and the vcpu would be stalled forever.
Although the hypercall has an "irq_disabled" argument.
But the hypervisor doesn't (and can't) touch the IRQ flags no matter
what the "irq_disabled" argument is. The IRQ is not enabled during
the halting if the IRQ is disabled before the hypercall even if
irq_disabled=false.
The "irq_disabled" argument is used for workaround purposes:
https://lore.kernel.org/kvm/c020ee0b90c424a7010e979c9b32a28e9c488a51.1651774251.git.isaku.yamahata@intel.com/
Hope my immature/incorrect reply elicits a real response from
others.
Thanks
Lai
next prev parent reply other threads:[~2022-06-13 8:26 UTC|newest]
Thread overview: 105+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-08 14:27 [PATCH 00/36] cpuidle,rcu: Cleanup the mess Peter Zijlstra
2022-06-08 14:27 ` [PATCH 01/36] x86/perf/amd: Remove tracing from perf_lopwr_cb() Peter Zijlstra
2022-06-08 14:27 ` [PATCH 02/36] x86/idle: Replace x86_idle with a static_call Peter Zijlstra
2022-06-08 18:13 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 03/36] cpuidle/poll: Ensure IRQ state is invariant Peter Zijlstra
2022-07-06 13:51 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE Peter Zijlstra
2022-06-08 15:01 ` Rafael J. Wysocki
2022-06-08 15:48 ` Peter Zijlstra
2022-06-08 16:08 ` Rafael J. Wysocki
2022-06-09 23:49 ` Jacob Pan
2022-06-13 8:44 ` Peter Zijlstra
2022-06-16 21:26 ` Jacob Pan
2022-07-25 19:43 ` Michel Lespinasse
2022-07-28 17:20 ` Paul E. McKenney
2022-07-29 10:24 ` Michel Lespinasse
2022-07-29 14:59 ` Rafael J. Wysocki
2022-07-30 9:48 ` Michel Lespinasse
2022-07-30 19:52 ` Rafael J. Wysocki
2022-07-30 23:45 ` Michel Lespinasse
2022-07-29 15:26 ` Paul E. McKenney
2022-07-29 15:28 ` Paul E. McKenney
2022-07-30 9:40 ` Michel Lespinasse
2022-07-30 18:16 ` Paul E. McKenney
2022-06-08 14:27 ` [PATCH 05/36] cpuidle: Move IRQ state validation Peter Zijlstra
2022-07-06 13:54 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 06/36] cpuidle,riscv: Push RCU-idle into driver Peter Zijlstra
2022-06-08 14:27 ` [PATCH 07/36] cpuidle,tegra: " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 08/36] cpuidle,psci: " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 09/36] cpuidle,imx6: " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 10/36] cpuidle,omap3: " Peter Zijlstra
2022-06-13 12:33 ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 11/36] cpuidle,armada: " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 12/36] cpuidle,omap2: " Peter Zijlstra
2022-06-13 12:33 ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 13/36] cpuidle,dt: " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 14/36] cpuidle: Fix rcu_idle_*() usage Peter Zijlstra
2022-06-14 12:41 ` Mark Rutland
2022-06-14 16:40 ` Peter Zijlstra
2022-06-14 16:59 ` Mark Rutland
2022-07-26 9:56 ` Gautham R. Shenoy
2022-06-08 14:27 ` [PATCH 15/36] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() Peter Zijlstra
2022-06-14 16:13 ` Mark Rutland
2022-06-14 16:42 ` Peter Zijlstra
2022-06-14 16:53 ` Mark Rutland
2022-06-08 14:27 ` [PATCH 16/36] rcu: Fix rcu_idle_exit() Peter Zijlstra
2022-06-14 16:14 ` Mark Rutland
2022-06-15 0:44 ` Paul E. McKenney
2022-06-08 14:27 ` [PATCH 17/36] acpi_idle: Remove tracing Peter Zijlstra
2022-07-06 13:59 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 18/36] cpuidle: Annotate poll_idle() Peter Zijlstra
2022-07-06 14:00 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 19/36] objtool/idle: Validate __cpuidle code as noinstr Peter Zijlstra
2022-07-06 9:46 ` Geert Uytterhoeven
2022-06-08 14:27 ` [PATCH 20/36] arch/idle: Change arch_cpu_idle() IRQ behaviour Peter Zijlstra
2022-06-08 16:22 ` Arnd Bergmann
2022-06-14 16:22 ` Mark Rutland
2022-07-06 14:02 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 21/36] x86/tdx: Remove TDX_HCALL_ISSUE_STI Peter Zijlstra
2022-06-13 8:26 ` Lai Jiangshan [this message]
2022-06-13 8:41 ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 22/36] arm,smp: Remove trace_.*_rcuidle() usage Peter Zijlstra
2022-06-08 14:27 ` [PATCH 23/36] arm64,smp: " Peter Zijlstra
2022-06-14 16:24 ` Mark Rutland
2022-06-15 6:05 ` Marc Zyngier
2022-06-08 14:27 ` [PATCH 24/36] printk: " Peter Zijlstra
2022-06-09 9:16 ` Petr Mladek
2022-06-09 10:02 ` Peter Zijlstra
2022-06-09 11:30 ` Sergey Senozhatsky
2022-06-09 13:02 ` Petr Mladek
2022-06-11 2:33 ` Sergey Senozhatsky
2022-06-14 14:37 ` Steven Rostedt
2022-06-09 13:06 ` Petr Mladek
2022-06-11 2:23 ` Sergey Senozhatsky
2022-06-09 10:14 ` Petr Mladek
2022-06-08 14:27 ` [PATCH 25/36] time/tick-broadcast: Remove RCU_NONIDLE usage Peter Zijlstra
2022-06-14 16:28 ` Mark Rutland
2022-06-08 14:27 ` [PATCH 26/36] cpuidle,sched: Remove annotations from TIF_{POLLING_NRFLAG,NEED_RESCHED} Peter Zijlstra
2022-06-08 14:27 ` [PATCH 27/36] cpuidle,mwait: Make noinstr clean Peter Zijlstra
2022-06-08 14:27 ` [PATCH 28/36] cpuidle,tdx: Make tdx " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 29/36] cpuidle,xenpv: Make more PARAVIRT_XXL " Peter Zijlstra
2022-06-13 18:48 ` Srivatsa S. Bhat
2022-06-13 19:23 ` [Pv-drivers] [PATCH 29/36] cpuidle, xenpv: " Nadav Amit
2022-06-14 16:44 ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 30/36] cpuidle,nospec: Make " Peter Zijlstra
2022-06-08 14:27 ` [PATCH 31/36] cpuidle,acpi: " Peter Zijlstra
2022-07-06 14:04 ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 32/36] ftrace: WARN on rcuidle Peter Zijlstra
2022-06-08 14:27 ` [PATCH 33/36] cpuidle,omap3: Use WFI for omap3_pm_idle() Peter Zijlstra
2022-06-08 16:28 ` Arnd Bergmann
2022-06-09 7:39 ` Tony Lindgren
2022-06-09 9:47 ` Peter Zijlstra
2022-06-09 9:40 ` Peter Zijlstra
2022-06-13 12:36 ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 34/36] cpuidle,omap3: Push RCU-idle into omap_sram_idle() Peter Zijlstra
2022-06-08 15:04 ` Peter Zijlstra
2022-06-13 12:35 ` Tony Lindgren
2022-06-13 12:39 ` [PATCH 34.5/36] cpuidle,omap4: Push RCU-idle into omap4_enter_lowpower() Tony Lindgren
2022-06-14 22:12 ` Peter Zijlstra
2022-06-15 5:35 ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 35/36] cpuidle,powerdomain: Remove trace_.*_rcuidle() Peter Zijlstra
2022-06-08 14:27 ` [PATCH 36/36] cpuidle,clk: " Peter Zijlstra
2022-06-14 11:19 ` [PATCH 00/36] cpuidle,rcu: Cleanup the mess Mark Rutland
2022-06-14 16:58 ` Peter Zijlstra
2022-06-14 17:33 ` Mark Rutland
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='CAJhGHyCnu_BsKf5STMMJKMWm0NVZ8qXT8Qh=BhhCjSSgwchL3Q@mail.gmail.com' \
--to=jiangshanlai@gmail.com \
--cc=James.Bottomley@hansenpartnership.com \
--cc=acme@kernel.org \
--cc=agordeev@linux.ibm.com \
--cc=agross@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=amakhalov@vmware.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=anton.ivanov@cambridgegreys.com \
--cc=anup@brainfault.org \
--cc=aou@eecs.berkeley.edu \
--cc=arnd@arndb.de \
--cc=bcain@quicinc.com \
--cc=benh@kernel.crashing.org \
--cc=bjorn.andersson@linaro.org \
--cc=boris.ostrovsky@oracle.com \
--cc=borntraeger@linux.ibm.com \
--cc=bp@alien8.de \
--cc=bristot@redhat.com \
--cc=bsegall@google.com \
--cc=catalin.marinas@arm.com \
--cc=chenhuacai@kernel.org \
--cc=chris@zankel.net \
--cc=dalias@libc.org \
--cc=daniel.lezcano@linaro.org \
--cc=dave.hansen@linux.intel.com \
--cc=davem@davemloft.net \
--cc=deller@gmx.de \
--cc=dietmar.eggemann@arm.com \
--cc=dinguyen@kernel.org \
--cc=festevam@gmail.com \
--cc=frederic@kernel.org \
--cc=geert@linux-m68k.org \
--cc=gor@linux.ibm.com \
--cc=gregkh@linuxfoundation.org \
--cc=guoren@kernel.org \
--cc=hca@linux.ibm.com \
--cc=hpa@zytor.com \
--cc=ink@jurassic.park.msu.ru \
--cc=isaku.yamahata@gmail.com \
--cc=jacob.jun.pan@linux.intel.com \
--cc=jcmvbkbc@gmail.com \
--cc=jgross@suse.com \
--cc=joel@joelfernandes.org \
--cc=johannes@sipsolutions.net \
--cc=john.ogness@linutronix.de \
--cc=jolsa@kernel.org \
--cc=jonas@southpole.se \
--cc=jonathanh@nvidia.com \
--cc=josh@joshtriplett.org \
--cc=jpoimboe@kernel.org \
--cc=juri.lelli@redhat.com \
--cc=kernel@pengutronix.de \
--cc=kernel@xen0n.name \
--cc=khilman@kernel.org \
--cc=kirill.shutemov@linux.intel.com \
--cc=lenb@kernel.org \
--cc=linus.walleij@linaro.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-alpha@vger.kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-csky@vger.kernel.org \
--cc=linux-hexagon@vger.kernel.org \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-imx@nxp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-m68k@lists.linux-m68k.org \
--cc=linux-mips@vger.kernel.org \
--cc=linux-omap@vger.kernel.org \
--cc=linux-parisc@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=linux-s390@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=linux-snps-arc@lists.infradead.org \
--cc=linux-tegra@vger.kernel.org \
--cc=linux-um@lists.infradead.org \
--cc=linux-xtensa@linux-xtensa.org \
--cc=linux@armlinux.org.uk \
--cc=linux@rasmusvillemoes.dk \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=lpieralisi@kernel.org \
--cc=mark.rutland@arm.com \
--cc=mathieu.desnoyers@efficios.com \
--cc=mattst88@gmail.com \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=monstr@monstr.eu \
--cc=mpe@ellerman.id.au \
--cc=mturquette@baylibre.com \
--cc=namhyung@kernel.org \
--cc=openrisc@lists.librecores.org \
--cc=palmer@dabbelt.com \
--cc=paul.walmsley@sifive.com \
--cc=paulmck@kernel.org \
--cc=paulus@samba.org \
--cc=pavel@ucw.cz \
--cc=peterz@infradead.org \
--cc=pmladek@suse.com \
--cc=pv-drivers@vmware.com \
--cc=quic_neeraju@quicinc.com \
--cc=rafael@kernel.org \
--cc=rcu@vger.kernel.org \
--cc=richard@nod.at \
--cc=rostedt@goodmis.org \
--cc=rth@twiddle.net \
--cc=s.hauer@pengutronix.de \
--cc=sammy@sammy.net \
--cc=sboyd@kernel.org \
--cc=senozhatsky@chromium.org \
--cc=shawnguo@kernel.org \
--cc=shorne@gmail.com \
--cc=sparclinux@vger.kernel.org \
--cc=srivatsa@csail.mit.edu \
--cc=stefan.kristiansson@saunalahti.fi \
--cc=sudeep.holla@arm.com \
--cc=svens@linux.ibm.com \
--cc=tglx@linutronix.de \
--cc=thierry.reding@gmail.com \
--cc=tony@atomide.com \
--cc=tsbogend@alpha.franken.de \
--cc=ulli.kroll@googlemail.com \
--cc=vgupta@kernel.org \
--cc=vincent.guittot@linaro.org \
--cc=virtualization@lists.linux-foundation.org \
--cc=vschneid@redhat.com \
--cc=will@kernel.org \
--cc=x86@kernel.org \
--cc=xen-devel@lists.xenproject.org \
--cc=ysato@users.sourceforge.jp \
--cc=yury.norov@gmail.com \
/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).