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From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	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@kernel.org, guoren@kernel.org, bcain@quicinc.com,
	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,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	paul.walmsley@sifive.com, palmer@dabbelt.com,
	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@nod.at,
	anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
	acme@kernel.org, mark.rutland@arm.com,
	alexander.shishkin@linux.intel.com, jolsa@kernel.org,
	namhyung@kernel.org, jgross@suse.com, srivatsa@csail.mit.edu,
	amakhalov@vmware.com, pv-drivers@vmware.com,
	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@brainfault.org,
	thierry.reding@gmail.com, jonathanh@nvidia.com,
	jacob.jun.pan@linux.intel.com, Arnd Bergmann <arnd@arndb.de>,
	yury.norov@gmail.com, andriy.shevchenko@linux.intel.com,
	linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com,
	senozhatsky@chromium.org, john.ogness@linutronix.de,
	frederic@kernel.org, quic_neeraju@quicinc.com,
	josh@joshtriplett.org, mathieu.desnoyers@efficios.com,
	jiangshanlai@gmail.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, rh0@fb.com
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	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@kernel.org, guoren@kernel.org, bcain@quicinc.com,
	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,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	paul.walmsley@sifive.com, palmer@dabbelt.com,
	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@nod.at,
	anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
	acme@kernel.org, mark.rutland@arm.com,
	alexander.shishkin@linux.intel.com, jolsa@kernel.org,
	namhyung@kernel.org, jgross@suse.com, srivatsa@csail.mit.edu,
	amakhalov@vmware.com, pv-drivers@vmware.com,
	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@brainfault.org,
	thierry.reding@gmail.com, jonathanh@nvidia.com,
	jacob.jun.pan@linux.intel.com, Arnd Bergmann <arnd@arndb.de>,
	yury.norov@gmail.com, andriy.shevchenko@linux.intel.com,
	linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com,
	senozhatsky@chromium.org, john.ogness@linutronix.de,
	frederic@kernel.org, quic_neeraju@quicinc.com,
	josh@joshtriplett.org, mathieu.desnoyers@efficios.com,
	jiangshanlai@gmail.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, rh0@fb.com
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

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WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	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@kernel.org, guoren@kernel.org, bcain@quicinc.com,
	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,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	paul.walmsley@sifive.com, palmer@dabbelt.com,
	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@nod.at,
	anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
	acme@kernel.org, mark.rutland@arm.com,
	alexander.shishkin@linux.intel.com, jolsa@kernel.org,
	namhyung@kernel.org, jgross@suse.com, srivatsa@csail.mit.edu,
	amakhalov@vmware.com, pv-drivers@vmware.com,
	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@brainfault.org,
	thierry.reding@gmail.com, jonathanh@nvidia.com,
	jacob.jun.pan@linux.intel.com, Arnd Bergmann <arnd@arndb.de>,
	yury.norov@gmail.com, andriy.shevchenko@linux.intel.com,
	linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com,
	senozhatsky@chromium.org, john.ogness@linutronix.de,
	frederic@kernel.org, quic_neeraju@quicinc.com,
	josh@joshtriplett.org, mathieu.desnoyers@efficios.com,
	jiangshanlai@gmail.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, rh0@fb.com
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

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WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: juri.lelli@redhat.com, rafael@kernel.org,
	benh@kernel.crashing.org, linus.walleij@linaro.org,
	bsegall@google.com, guoren@kernel.org, pavel@ucw.cz,
	agordeev@linux.ibm.com, srivatsa@csail.mit.edu,
	linux-arch@vger.kernel.org, vincent.guittot@linaro.org,
	mpe@ellerman.id.au, chenhuacai@kernel.org,
	linux-acpi@vger.kernel.org, agross@kernel.org, linux-imx@nxp.com,
	catalin.marinas@arm.com, xen-devel@lists.xenproject.org,
	mattst88@gmail.com, borntraeger@linux.ibm.com,
	mturquette@baylibre.com, sammy@sammy.net, pmladek@suse.com,
	linux-pm@vger.kernel.org, jiangshanlai@gmail.com,
	Sascha Hauer <s.hauer@pengutronix.de>,
	linux-um@lists.infradead.org, acme@kernel.org,
	tglx@linutronix.de, linux-omap@vger.kernel.org,
	dietmar.eggemann@arm.com, rth@twiddle.net,
	gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	linux-perf-users@vger.kernel.org, senozhatsky@chromium.org,
	svens@linux.ibm.com, jolsa@kernel.org, paulus@samba.org,
	mark.rutland@arm.com, linux-ia64@vger.kernel.org,
	dave.hansen@linux.intel.com,
	virtualization@lists.linux-foundation.org,
	James.Bottomley@HansenPartnership.com, jcmvbkbc@gmail.com,
	thierry.reding@gmail.com, kernel@xen0n.name,
	quic_neeraju@quicinc.com, linux-s390@vger.kernel.org,
	vschneid@redhat.com, john.ogness@linutronix.de,
	ysato@users.sourceforge.jp, linux-sh@vger.kernel.org,
	festevam@gmail.com, deller@gmx.de, daniel.lezcano@linaro.org,
	jonathanh@nvidia.com, mathieu.desnoyers@efficios.com,
	frederic@kernel.org, lenb@kernel.org,
	linux-xtensa@linux-xtensa.org, kernel@pengutronix.de,
	gor@linux.ibm.com, linux-arm-msm@vger.kernel.org,
	linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org,
	linux-arm-kernel@lists.infradead.org, chris@zankel.net,
	sboyd@kernel.org, rh0@fb.com, dinguyen@kernel.org,
	bristot@redhat.com, alexander.shishkin@linux.intel.com,
	lpieralisi@kernel.org, linux@rasmusvillemoes.dk,
	joel@joelfernandes.org, will@kernel.org,
	boris.ostrovsky@oracle.com, josh@joshtriplett.org,
	khilman@kernel.org, linux-csky@vger.kernel.org, tony@atomide.com,
	linux-snps-arc@lists.infradead.org, mgorman@suse.de,
	jacob.jun.pan@linux.intel.com, yury.norov@gmail.com,
	ulli.kroll@googlemail.com, vgupta@kernel.org,
	linux-clk@vger.kernel.org, monstr@monstr.eu, rostedt@goodmis.org,
	rcu@vger.kernel.org, bp@alien8.de, bcain@quicinc.com,
	tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org,
	sudeep.holla@arm.com, shawnguo@kernel.org, davem@davemloft.net,
	dalias@libc.org, Peter Zijlstra <peterz@infradead.org>,
	amakhalov@vmware.com, bjorn.andersson@linaro.org, hpa@zytor.com,
	sparclinux@vger.kernel.org, linux-hexagon@vger.kernel.org,
	linux-riscv@lists.infradead.org, anton.ivanov@cambridgegreys.com,
	jonas@southpole.se, Arnd Bergmann <arnd@arndb.de>,
	richard@nod.at, x86@kernel.org, linux@armlinux.org.uk,
	mingo@redhat.com, aou@eecs.berkeley.edu, hca@linux.ibm.com,
	openrisc@lists.librecores.org, paul.walmsley@sifive.com,
	linux-tegra@vger.kernel.org, namhyung@kernel.org,
	andriy.shevchenko@linux.intel.com, jpoimboe@kernel.org,
	jgross@suse.com, pv-drivers@vmware.com,
	linux-mips@vger.kernel.org, palmer@dabbelt.com,
	anup@brainfault.org, ink@jurassic.park.msu.ru,
	johannes@sipsolutions.net, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: juri.lelli@redhat.com, rafael@kernel.org,
	linus.walleij@linaro.org, bsegall@google.com, guoren@kernel.org,
	pavel@ucw.cz, agordeev@linux.ibm.com, srivatsa@csail.mit.edu,
	linux-arch@vger.kernel.org, vincent.guittot@linaro.org,
	chenhuacai@kernel.org, linux-acpi@vger.kernel.org,
	agross@kernel.org, geert@linux-m68k.org, linux-imx@nxp.com,
	catalin.marinas@arm.com, xen-devel@lists.xenproject.org,
	mattst88@gmail.com, borntraeger@linux.ibm.com,
	mturquette@baylibre.com, sammy@sammy.net, pmladek@suse.com,
	linux-pm@vger.kernel.org, jiangshanlai@gmail.com,
	Sascha Hauer <s.hauer@pengutronix.de>,
	linux-um@lists.infradead.org, acme@kernel.org,
	tglx@linutronix.de, linux-omap@vger.kernel.org,
	dietmar.eggemann@arm.com, rth@twiddle.net,
	gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	linux-perf-users@vger.kernel.org, senozhatsky@chromium.org,
	svens@linux.ibm.com, jolsa@kernel.org, paulus@samba.org,
	mark.rutland@arm.com, linux-ia64@vger.kernel.org,
	dave.hansen@linux.intel.com,
	virtualizatio n@lists.linux-foundation.org,
	James.Bottomley@HansenPartnership.com, jcmvbkbc@gmail.com,
	thierry.reding@gmail.com, kernel@xen0n.name,
	quic_neeraju@quicinc.com, linux-s390@vger.kernel.org,
	vschneid@redhat.com, john.ogness@linutronix.de,
	ysato@users.sourceforge.jp, linux-sh@vger.kernel.org,
	festevam@gmail.com, deller@gmx.de, daniel.lezcano@linaro.org,
	jonathanh@nvidia.com, mathieu.desnoyers@efficios.com,
	frederic@kernel.org, lenb@kernel.org,
	linux-xtensa@linux-xtensa.org, kernel@pengutronix.de,
	gor@linux.ibm.com, linux-arm-msm@vger.kernel.org,
	linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org,
	shorne@gmail.com, linux-arm-kernel@lists.infradead.org,
	chris@zankel.net, sboyd@kernel.org, rh0@fb.com,
	dinguyen@kernel.org, bristot@redhat.com,
	alexander.shishkin@linux.intel.com, lpieralisi@kernel.org,
	linux@rasmusvillemoes.dk, joel@joelfernandes.org,
	will@kernel.org, boris.ostrovsky@oracle.com,
	josh@joshtriplett.org, khilman@kernel.org,
	linux-csky@vger.kernel.org, tony@atomide.com,
	linux-snps-arc@lists.infradead.org, mgorman@suse.de,
	jacob.jun.pan@linux.intel.com, yury.norov@gmail.com,
	ulli.kroll@googlemail.com, vgupta@kernel.org,
	linux-clk@vger.kernel.org, monstr@monstr.eu, rostedt@goodmis.org,
	rcu@vger.kernel.org, bp@alien8.de, bcain@quicinc.com,
	tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org,
	sudeep.holla@arm.com, shawnguo@kernel.org, davem@davemloft.net,
	dalias@libc.org, Peter Zijlstra <peterz@infradead.org>,
	amakhalov@vmware.com, bjorn.andersson@linaro.org, hpa@zytor.com,
	sparclinux@vger.kernel.org, linux-hexagon@vger.kernel.org,
	linux-riscv@lists.infradead.org, anton.ivanov@cambridgegreys.com,
	jonas@southpole.se, Arnd Bergmann <arnd@arndb.de>,
	richard@nod.at, x86@kernel.org, linux@armlinux.org.uk,
	mingo@redhat.com, aou@eecs.berkeley.edu, hca@linux.ibm.com,
	stefan.kristiansson@saunalahti.fi, openrisc@lists.librecores.org,
	paul.walmsley@sifive.com, linux-tegra@vger.kernel.org,
	namhyung@kernel.org, andriy.shevchenko@linux.intel.com,
	jpoimboe@kerne l.org, jgross@suse.com, pv-drivers@vmware.com,
	linux-mips@vger.kernel.org, palmer@dabbelt.com,
	anup@brainfault.org, ink@jurassic.park.msu.ru,
	johannes@sipsolutions.net, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	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@kernel.org, guoren@kernel.org, bcain@quicinc.com,
	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,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	paul.walmsley@sifive.com, palmer@dabbelt.com,
	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@nod.at,
	anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
	acme@kernel.org, mark.rutland@arm.com,
	alexander.shishkin@linux.intel.com, jolsa@kernel.org,
	namhyung@kernel.org, jgross@suse.com, srivatsa@csail.mit.edu,
	amakhalov@vmware.com, pv-drivers@vmware.com,
	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@brainfault.org,
	thierry.reding@gmail.com, jonathanh@nvidia.com,
	jacob.jun.pan@linux.intel.com, Arnd Bergmann <arnd@arndb.de>,
	yury.norov@gmail.com, andriy.shevchenko@linux.intel.com,
	linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com,
	senozhatsky@chromium.org, john.ogness@linutronix.de,
	frederic@kernel.org, quic_neeraju@quicinc.com,
	josh@joshtriplett.org, mathieu.desnoyers@efficios.com,
	jiangshanlai@gmail.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, rh0@fb.com
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 15:26:22 +0000	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

WARNING: multiple messages have this Message-ID (diff)
From: "Paul E. McKenney" <paulmck@kernel.org>
To: Michel Lespinasse <michel@lespinasse.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	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@kernel.org, guoren@kernel.org, bcain@quicinc.com,
	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,
	mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org,
	paul.walmsley@sif
Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE
Date: Fri, 29 Jul 2022 08:26:22 -0700	[thread overview]
Message-ID: <20220729152622.GM2860372@paulmck-ThinkPad-P17-Gen-1> (raw)
In-Reply-To: <20220729102458.GA1695@lespinasse.org>

On Fri, Jul 29, 2022 at 03:24:58AM -0700, Michel Lespinasse wrote:
> On Thu, Jul 28, 2022 at 10:20:53AM -0700, Paul E. McKenney wrote:
> > On Mon, Jul 25, 2022 at 12:43:06PM -0700, Michel Lespinasse wrote:
> > > On Wed, Jun 08, 2022 at 04:27:27PM +0200, Peter Zijlstra wrote:
> > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on
> > > > Xeons") wrecked intel_idle in two ways:
> > > > 
> > > >  - must not have tracing in idle functions
> > > >  - must return with IRQs disabled
> > > > 
> > > > Additionally, it added a branch for no good reason.
> > > > 
> > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on Xeons")
> > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > 
> > > After this change was introduced, I am seeing "WARNING: suspicious RCU
> > > usage" when booting a kernel with debug options compiled in. Please
> > > see the attached dmesg output. The issue starts with commit 32d4fd5751ea
> > > and is still present in v5.19-rc8.
> > > 
> > > I'm not sure, is this too late to fix or revert in v5.19 final ?
> > 
> > I finally got a chance to take a quick look at this.
> > 
> > The rcu_eqs_exit() function is making a lockdep complaint about
> > being invoked with interrupts enabled.  This function is called from
> > rcu_idle_exit(), which is an expected code path from cpuidle_enter_state()
> > via its call to rcu_idle_exit().  Except that rcu_idle_exit() disables
> > interrupts before invoking rcu_eqs_exit().
> > 
> > The only other call to rcu_idle_exit() does not disable interrupts,
> > but it is via rcu_user_exit(), which would be a very odd choice for
> > cpuidle_enter_state().
> > 
> > It seems unlikely, but it might be that it is the use of local_irq_save()
> > instead of raw_local_irq_save() within rcu_idle_exit() that is causing
> > the trouble.  If this is the case, then the commit shown below would
> > help.  Note that this commit removes the warning from lockdep, so it
> > is necessary to build the kernel with CONFIG_RCU_EQS_DEBUG=y to enable
> > equivalent debugging.
> > 
> > Could you please try your test with the -rce commit shown below applied?
> 
> Thanks for looking into it.

And thank you for trying this shot in the dark!

> After checking out Peter's commit 32d4fd5751ea,
> cherry picking your commit ed4ae5eff4b3,
> and setting CONFIG_RCU_EQS_DEBUG=y in addition of my usual debug config,
> I am now seeing this a few seconds into the boot:
> 
> [    3.010650] ------------[ cut here ]------------
> [    3.010651] WARNING: CPU: 0 PID: 0 at kernel/sched/clock.c:397 sched_clock_tick+0x27/0x60

And this is again a complaint about interrupts not being disabled.

But it does appear that the problem was the lockdep complaint, and
eliminating that did take care of part of the problem.  But lockdep
remained enabled, and you therefore hit the next complaint.

> [    3.010657] Modules linked in:
> [    3.010660] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc1-test-00005-g1be22fea0611 #1
> [    3.010662] Hardware name: LENOVO 30BFS44D00/1036, BIOS S03KT51A 01/17/2022
> [    3.010663] RIP: 0010:sched_clock_tick+0x27/0x60

The most straightforward way to get to sched_clock_tick() from
cpuidle_enter_state() is via the call to sched_clock_idle_wakeup_event().

Except that it disables interrupts before invoking sched_clock_tick().

> [    3.010665] Code: 1f 40 00 53 eb 02 5b c3 66 90 8b 05 2f c3 40 01 85 c0 74 18 65 8b 05 60 88 8f 4e 85 c0 75 0d 65 8b 05 a9 85 8f 4e 85 c0 74 02 <0f> 0b e8 e2 6c 89 00 48 c7 c3 40 d5 02 00
>  89 c0 48 03 1c c5 c0 98
> [    3.010667] RSP: 0000:ffffffffb2803e28 EFLAGS: 00010002
> [    3.010670] RAX: 0000000000000001 RBX: ffffc8ce7fa07060 RCX: 0000000000000001
> [    3.010671] RDX: 0000000000000000 RSI: ffffffffb268dd21 RDI: ffffffffb269ab13
> [    3.010673] RBP: 0000000000000001 R08: ffffffffffc300d5 R09: 000000000002be80
> [    3.010674] R10: 000003625b53183a R11: ffffa012b802b7a4 R12: ffffffffb2aa9e80
> [    3.010675] R13: ffffffffb2aa9e00 R14: 0000000000000001 R15: 0000000000000000
> [    3.010677] FS:  0000000000000000(0000) GS:ffffa012b8000000(0000) knlGS:0000000000000000
> [    3.010678] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    3.010680] CR2: ffffa012f81ff000 CR3: 0000000c99612001 CR4: 00000000003706f0
> [    3.010681] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [    3.010682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [    3.010683] Call Trace:
> [    3.010685]  <TASK>
> [    3.010688]  cpuidle_enter_state+0xb7/0x4b0
> [    3.010694]  cpuidle_enter+0x29/0x40
> [    3.010697]  do_idle+0x1d4/0x210
> [    3.010702]  cpu_startup_entry+0x19/0x20
> [    3.010704]  rest_init+0x117/0x1a0
> [    3.010708]  arch_call_rest_init+0xa/0x10
> [    3.010711]  start_kernel+0x6d8/0x6ff
> [    3.010716]  secondary_startup_64_no_verify+0xce/0xdb
> [    3.010728]  </TASK>
> [    3.010729] irq event stamp: 44179
> [    3.010730] hardirqs last  enabled at (44179): [<ffffffffb2000ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20
> [    3.010734] hardirqs last disabled at (44177): [<ffffffffb22003f0>] __do_softirq+0x3f0/0x498
> [    3.010736] softirqs last  enabled at (44178): [<ffffffffb2200332>] __do_softirq+0x332/0x498
> [    3.010738] softirqs last disabled at (44171): [<ffffffffb16c760b>] irq_exit_rcu+0xab/0xf0
> [    3.010741] ---[ end trace 0000000000000000 ]---

Would you be willing to try another shot in the dark, but untested
this time?  I freely admit that this is getting strange.

							Thanx, Paul

------------------------------------------------------------------------

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index e374c0c923dae..279f557bf60bb 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -394,7 +394,7 @@ notrace void sched_clock_tick(void)
 	if (!static_branch_likely(&sched_clock_running))
 		return;
 
-	lockdep_assert_irqs_disabled();
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !raw_irqs_disabled());
 
 	scd = this_scd();
 	__scd_stamp(scd);

  parent reply	other threads:[~2022-07-29 15:26 UTC|newest]

Thread overview: 820+ 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 ` Peter Zijlstra
2022-06-08 14:27 ` Peter Zijlstra
2022-06-08 14:27 ` Peter Zijlstra
2022-06-08 14:27 ` Peter Zijlstra
2022-06-08 14:27 ` Peter Zijlstra
2022-06-08 14:27 ` Peter Zijlstra
2022-06-08 14:27 ` 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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 02/36] x86/idle: Replace x86_idle with a static_call Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 18:13   ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
2022-06-08 18:13     ` Rafael J. Wysocki
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
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06 13:51   ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
2022-07-06 13:51     ` Rafael J. Wysocki
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 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 15:01   ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:01     ` Rafael J. Wysocki
2022-06-08 15:48     ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 15:48       ` Peter Zijlstra
2022-06-08 16:08       ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-08 16:08         ` Rafael J. Wysocki
2022-06-09 23:49   ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-09 23:49     ` Jacob Pan
2022-06-13  8:44     ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-13  8:44       ` Peter Zijlstra
2022-06-16 21:26       ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-06-16 21:26         ` Jacob Pan
2022-07-25 19:43   ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-25 19:43     ` Michel Lespinasse
2022-07-28 17:20     ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-28 17:20       ` Paul E. McKenney
2022-07-29 10:24       ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 10:24         ` Michel Lespinasse
2022-07-29 14:59         ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-29 14:59           ` Rafael J. Wysocki
2022-07-30  9:48           ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30  9:48             ` Michel Lespinasse
2022-07-30 19:52             ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 19:52               ` Rafael J. Wysocki
2022-07-30 23:45               ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-30 23:45                 ` Michel Lespinasse
2022-07-29 15:26         ` Paul E. McKenney [this message]
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:26           ` Paul E. McKenney
2022-07-29 15:28           ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-29 15:28             ` Paul E. McKenney
2022-07-30  9:40           ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30  9:40             ` Michel Lespinasse
2022-07-30 18:16             ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-07-30 18:16               ` Paul E. McKenney
2022-06-08 14:27 ` [PATCH 05/36] cpuidle: Move IRQ state validation Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06 13:54   ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
2022-07-06 13:54     ` Rafael J. Wysocki
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 07/36] cpuidle,tegra: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 08/36] cpuidle,psci: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 09/36] cpuidle,imx6: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 10/36] cpuidle,omap3: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-13 12:33   ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 11/36] cpuidle,armada: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 12/36] cpuidle,omap2: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-13 12:33   ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-13 12:33     ` Tony Lindgren
2022-06-08 14:27 ` [PATCH 13/36] cpuidle,dt: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 14/36] cpuidle: Fix rcu_idle_*() usage Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-14 12:41   ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 12:41     ` Mark Rutland
2022-06-14 16:40     ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:40       ` Peter Zijlstra
2022-06-14 16:59       ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-06-14 16:59         ` Mark Rutland
2022-07-26  9:55   ` Gautham R. Shenoy
2022-07-26  9:56     ` Gautham R. Shenoy
2022-07-26  9:56     ` Gautham R. Shenoy
2022-07-26  9:56     ` Gautham R. Shenoy
2022-07-26  9:56     ` Gautham R. Shenoy
2022-07-26  9:56     ` Gautham R. Shenoy
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
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` [PATCH 15/36] cpuidle, cpu_pm: Remove RCU fiddling from cpu_pm_{enter, exit}() Peter Zijlstra
2022-06-08 14:27   ` [PATCH 15/36] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
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   ` [PATCH 15/36] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:13     ` Mark Rutland
2022-06-14 16:42     ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:42       ` Peter Zijlstra
2022-06-14 16:53       ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-14 16:53         ` Mark Rutland
2022-06-08 14:27 ` [PATCH 16/36] rcu: Fix rcu_idle_exit() Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-14 16:14   ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-14 16:14     ` Mark Rutland
2022-06-15  0:44   ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-15  0:44     ` Paul E. McKenney
2022-06-08 14:27 ` [PATCH 17/36] acpi_idle: Remove tracing Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06 13:59   ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-07-06 13:59     ` Rafael J. Wysocki
2022-06-08 14:27 ` [PATCH 18/36] cpuidle: Annotate poll_idle() Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06 13:59   ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
2022-07-06 14:00     ` Rafael J. Wysocki
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
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06  9:46   ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
2022-07-06  9:46     ` Geert Uytterhoeven
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 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 16:22   ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-08 16:22     ` Arnd Bergmann
2022-06-14 16:22   ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-06-14 16:22     ` Mark Rutland
2022-07-06 14:02   ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
2022-07-06 14:02     ` Rafael J. Wysocki
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
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-13  8:26   ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:26     ` Lai Jiangshan
2022-06-13  8:41     ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
2022-06-13  8:41       ` Peter Zijlstra
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 23/36] arm64,smp: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-14 16:24   ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-14 16:24     ` Mark Rutland
2022-06-15  6:05     ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-15  6:05       ` Marc Zyngier
2022-06-08 14:27 ` [PATCH 24/36] printk: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-09  9:16   ` Petr Mladek
2022-06-09  9:16     ` Petr Mladek
2022-06-09  9:16     ` Petr Mladek
2022-06-09  9:16     ` Petr Mladek
2022-06-09  9:16     ` Petr Mladek
2022-06-09  9:16     ` Petr Mladek via Virtualization
2022-06-09 10:02     ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 10:02       ` Peter Zijlstra
2022-06-09 11:30       ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 11:30         ` Sergey Senozhatsky
2022-06-09 13:02         ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek
2022-06-09 13:02           ` Petr Mladek via Virtualization
2022-06-09 13:02           ` Petr Mladek
2022-06-11  2:33           ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-11  2:33             ` Sergey Senozhatsky
2022-06-14 14:37           ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-14 14:37             ` Steven Rostedt
2022-06-09 13:06       ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek
2022-06-09 13:06         ` Petr Mladek via Virtualization
2022-06-09 13:06         ` Petr Mladek
2022-06-11  2:23         ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-11  2:23           ` Sergey Senozhatsky
2022-06-09 10:14   ` Petr Mladek
2022-06-09 10:14     ` Petr Mladek
2022-06-09 10:14     ` Petr Mladek
2022-06-09 10:14     ` Petr Mladek
2022-06-09 10:14     ` Petr Mladek
2022-06-09 10:14     ` Petr Mladek via Virtualization
2022-06-08 14:27 ` [PATCH 25/36] time/tick-broadcast: Remove RCU_NONIDLE usage Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-14 16:28   ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
2022-06-14 16:28     ` Mark Rutland
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
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 26/36] cpuidle,sched: Remove annotations from TIF_{POLLING_NRFLAG,NEED_RESCHED} Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 28/36] cpuidle,tdx: Make tdx " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 29/36] cpuidle,xenpv: Make more PARAVIRT_XXL " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-13 18:48   ` Srivatsa S. Bhat
2022-06-13 18:48     ` [PATCH 29/36] cpuidle, xenpv: " Srivatsa S. Bhat
2022-06-13 18:48     ` [PATCH 29/36] cpuidle,xenpv: " Srivatsa S. Bhat
2022-06-13 18:48     ` Srivatsa S. Bhat
2022-06-13 18:48     ` [PATCH 29/36] cpuidle, xenpv: " Srivatsa S. Bhat
2022-06-13 18:48     ` [PATCH 29/36] cpuidle,xenpv: " Srivatsa S. Bhat
2022-06-13 18:48     ` Srivatsa S. Bhat
2022-06-13 18:48     ` [PATCH 29/36] cpuidle, xenpv: " Srivatsa S. Bhat
2022-06-13 19:23     ` [Pv-drivers] " Nadav Amit
2022-06-13 19:23       ` Nadav Amit via Virtualization
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit
2022-06-13 19:23       ` Nadav Amit via Virtualization
2022-06-14 16:44       ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
2022-06-14 16:44         ` Peter Zijlstra
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 31/36] cpuidle,acpi: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-07-06 14:04   ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
2022-07-06 14:04     ` Rafael J. Wysocki
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   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 33/36] cpuidle,omap3: Use WFI for omap3_pm_idle() Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 16:28   ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-08 16:28     ` Arnd Bergmann
2022-06-09  7:39     ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  7:39       ` Tony Lindgren
2022-06-09  9:47       ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:47         ` Peter Zijlstra
2022-06-09  9:40     ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-09  9:40       ` Peter Zijlstra
2022-06-13 12:36   ` Tony Lindgren
2022-06-13 12:36     ` Tony Lindgren
2022-06-13 12:36     ` Tony Lindgren
2022-06-13 12:36     ` Tony Lindgren
2022-06-13 12:36     ` Tony Lindgren
2022-06-13 12:36     ` Tony Lindgren
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 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 15:04   ` Peter Zijlstra
2022-06-08 15:04     ` Peter Zijlstra
2022-06-08 15:04     ` Peter Zijlstra
2022-06-08 15:04     ` Peter Zijlstra
2022-06-08 15:04     ` Peter Zijlstra
2022-06-13 12:35     ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-13 12:35       ` Tony Lindgren
2022-06-08 15:04   ` Peter Zijlstra
2022-06-08 15:04   ` Peter Zijlstra
2022-06-13 12:39   ` [PATCH 34.5/36] cpuidle,omap4: Push RCU-idle into omap4_enter_lowpower() Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-13 12:39     ` Tony Lindgren
2022-06-14 22:12     ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-14 22:12       ` Peter Zijlstra
2022-06-15  5:35       ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2022-06-15  5:35         ` Tony Lindgren
2023-01-13 12:31     ` [tip: sched/core] cpuidle, OMAP4: " tip-bot2 for Tony Lindgren
2022-06-08 14:27 ` [PATCH 35/36] cpuidle,powerdomain: Remove trace_.*_rcuidle() Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27 ` [PATCH 36/36] cpuidle,clk: " Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 14:27   ` Peter Zijlstra
2022-06-08 20:03   ` Stephen Boyd
2022-06-08 20:03     ` Stephen Boyd
2022-06-08 20:03     ` Stephen Boyd
2022-06-08 20:03     ` Stephen Boyd
2022-06-14 11:19 ` [PATCH 00/36] cpuidle,rcu: Cleanup the mess Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 11:19   ` Mark Rutland
2022-06-14 16:58   ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 16:58     ` Peter Zijlstra
2022-06-14 17:33     ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland
2022-06-14 17:33       ` Mark Rutland

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