[PATCH AUTOSEL 5.9 09/39] powerpc: Drop -me200 addition to build flags

[PATCH AUTOSEL 5.9 09/39] powerpc: Drop -me200 addition to build flags

[Sasha Levin]

From: Michael Ellerman <mpe@ellerman.id.au>

[ Upstream commit e02152ba2810f7c88cb54e71cda096268dfa9241 ]

Currently a build with CONFIG_E200=y will fail with:

  Error: invalid switch -me200
  Error: unrecognized option -me200

Upstream binutils has never supported an -me200 option. Presumably it
was supported at some point by either a fork or Freescale internal
binutils.

We can't support code that we can't even build test, so drop the
addition of -me200 to the build flags, so we can at least build with
CONFIG_E200=y.

Reported-by: Németh Márton <nm127@freemail.hu>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Scott Wood <oss@buserror.net>
Link: https://lore.kernel.org/r/20201116120913.165317-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 3e8da9cf2eb9d..e6643d5699fef 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -249,7 +249,6 @@ KBUILD_CFLAGS		+= $(call cc-option,-mno-string)
 cpu-as-$(CONFIG_40x)		+= -Wa,-m405
 cpu-as-$(CONFIG_44x)		+= -Wa,-m440
 cpu-as-$(CONFIG_ALTIVEC)	+= $(call as-option,-Wa$(comma)-maltivec)
-cpu-as-$(CONFIG_E200)		+= -Wa,-me200
 cpu-as-$(CONFIG_E500)		+= -Wa,-me500
 
 # When using '-many -mpower4' gas will first try and find a matching power4
-- 
2.27.0

[PATCH AUTOSEL 5.9 18/39] ibmvnic: skip tx timeout reset while in resetting

[Sasha Levin]

From: Lijun Pan <ljp@linux.ibm.com>

[ Upstream commit 855a631a4c11458a9cef1ab79c1530436aa95fae ]

Sometimes it takes longer than 5 seconds (watchdog timeout) to complete
failover, migration, and other resets. In stead of scheduling another
timeout reset, we wait for the current one to complete.

Suggested-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Reviewed-by: Dany Madden <drt@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 81ec233926acb..37012aa594f41 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -2368,6 +2368,12 @@ static void ibmvnic_tx_timeout(struct net_device *dev, unsigned int txqueue)
 {
 	struct ibmvnic_adapter *adapter = netdev_priv(dev);
 
+	if (test_bit(0, &adapter->resetting)) {
+		netdev_err(adapter->netdev,
+			   "Adapter is resetting, skip timeout reset\n");
+		return;
+	}
+
 	ibmvnic_reset(adapter, VNIC_RESET_TIMEOUT);
 }
 
-- 
2.27.0

[PATCH AUTOSEL 5.9 26/39] soc: fsl: dpio: Get the cpumask through cpumask_of(cpu)

[Sasha Levin]

From: Hao Si <si.hao@zte.com.cn>

[ Upstream commit 2663b3388551230cbc4606a40fabf3331ceb59e4 ]

The local variable 'cpumask_t mask' is in the stack memory, and its address
is assigned to 'desc->affinity' in 'irq_set_affinity_hint()'.
But the memory area where this variable is located is at risk of being
modified.

During LTP testing, the following error was generated:

Unable to handle kernel paging request at virtual address ffff000012e9b790
Mem abort info:
  ESR = 0x96000007
  Exception class = DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000007
  CM = 0, WnR = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp = 0000000075ac5e07
[ffff000012e9b790] pgd=00000027dbffe003, pud=00000027dbffd003,
pmd=00000027b6d61003, pte=0000000000000000
Internal error: Oops: 96000007 [#1] PREEMPT SMP
Modules linked in: xt_conntrack
Process read_all (pid: 20171, stack limit = 0x0000000044ea4095)
CPU: 14 PID: 20171 Comm: read_all Tainted: G    B   W
Hardware name: NXP Layerscape LX2160ARDB (DT)
pstate: 80000085 (Nzcv daIf -PAN -UAO)
pc : irq_affinity_hint_proc_show+0x54/0xb0
lr : irq_affinity_hint_proc_show+0x4c/0xb0
sp : ffff00001138bc10
x29: ffff00001138bc10 x28: 0000ffffd131d1e0
x27: 00000000007000c0 x26: ffff8025b9480dc0
x25: ffff8025b9480da8 x24: 00000000000003ff
x23: ffff8027334f8300 x22: ffff80272e97d000
x21: ffff80272e97d0b0 x20: ffff8025b9480d80
x19: ffff000009a49000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000040
x11: 0000000000000000 x10: ffff802735b79b88
x9 : 0000000000000000 x8 : 0000000000000000
x7 : ffff000009a49848 x6 : 0000000000000003
x5 : 0000000000000000 x4 : ffff000008157d6c
x3 : ffff00001138bc10 x2 : ffff000012e9b790
x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 irq_affinity_hint_proc_show+0x54/0xb0
 seq_read+0x1b0/0x440
 proc_reg_read+0x80/0xd8
 __vfs_read+0x60/0x178
 vfs_read+0x94/0x150
 ksys_read+0x74/0xf0
 __arm64_sys_read+0x24/0x30
 el0_svc_common.constprop.0+0xd8/0x1a0
 el0_svc_handler+0x34/0x88
 el0_svc+0x10/0x14
Code: f9001bbf 943e0732 f94066c2 b4000062 (f9400041)
---[ end trace b495bdcb0b3b732b ]---
Kernel panic - not syncing: Fatal exception
SMP: stopping secondary CPUs
SMP: failed to stop secondary CPUs 0,2-4,6,8,11,13-15
Kernel Offset: disabled
CPU features: 0x0,21006008
Memory Limit: none
---[ end Kernel panic - not syncing: Fatal exception ]---

Fix it by using 'cpumask_of(cpu)' to get the cpumask.

Signed-off-by: Hao Si <si.hao@zte.com.cn>
Signed-off-by: Lin Chen <chen.lin5@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/soc/fsl/dpio/dpio-driver.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c
index 7b642c330977f..7f397b4ad878d 100644
--- a/drivers/soc/fsl/dpio/dpio-driver.c
+++ b/drivers/soc/fsl/dpio/dpio-driver.c
@@ -95,7 +95,6 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 {
 	int error;
 	struct fsl_mc_device_irq *irq;
-	cpumask_t mask;
 
 	irq = dpio_dev->irqs[0];
 	error = devm_request_irq(&dpio_dev->dev,
@@ -112,9 +111,7 @@ static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 	}
 
 	/* set the affinity hint */
-	cpumask_clear(&mask);
-	cpumask_set_cpu(cpu, &mask);
-	if (irq_set_affinity_hint(irq->msi_desc->irq, &mask))
+	if (irq_set_affinity_hint(irq->msi_desc->irq, cpumask_of(cpu)))
 		dev_err(&dpio_dev->dev,
 			"irq_set_affinity failed irq %d cpu %d\n",
 			irq->msi_desc->irq, cpu);
-- 
2.27.0

[PATCH AUTOSEL 5.9 27/39] sched/idle: Fix arch_cpu_idle() vs tracing

[Sasha Levin]

From: Peter Zijlstra <peterz@infradead.org>

[ Upstream commit 58c644ba512cfbc2e39b758dd979edd1d6d00e27 ]

We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.

Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.

(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)

Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/alpha/kernel/process.c      |  2 +-
 arch/arm/kernel/process.c        |  2 +-
 arch/arm64/kernel/process.c      |  2 +-
 arch/csky/kernel/process.c       |  2 +-
 arch/h8300/kernel/process.c      |  2 +-
 arch/hexagon/kernel/process.c    |  2 +-
 arch/ia64/kernel/process.c       |  2 +-
 arch/microblaze/kernel/process.c |  2 +-
 arch/mips/kernel/idle.c          | 12 ++++++------
 arch/nios2/kernel/process.c      |  2 +-
 arch/openrisc/kernel/process.c   |  2 +-
 arch/parisc/kernel/process.c     |  2 +-
 arch/powerpc/kernel/idle.c       |  4 ++--
 arch/riscv/kernel/process.c      |  2 +-
 arch/s390/kernel/idle.c          |  6 +++---
 arch/sh/kernel/idle.c            |  2 +-
 arch/sparc/kernel/leon_pmc.c     |  4 ++--
 arch/sparc/kernel/process_32.c   |  2 +-
 arch/sparc/kernel/process_64.c   |  4 ++--
 arch/um/kernel/process.c         |  2 +-
 arch/x86/include/asm/mwait.h     |  2 --
 arch/x86/kernel/process.c        | 12 +++++++-----
 kernel/sched/idle.c              | 28 +++++++++++++++++++++++++++-
 23 files changed, 64 insertions(+), 38 deletions(-)

diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index 7462a79110024..4c7b0414a3ff3 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -57,7 +57,7 @@ EXPORT_SYMBOL(pm_power_off);
 void arch_cpu_idle(void)
 {
 	wtint(0);
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 void arch_cpu_idle_dead(void)
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 8e6ace03e960b..9f199b1e83839 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -71,7 +71,7 @@ void arch_cpu_idle(void)
 		arm_pm_idle();
 	else
 		cpu_do_idle();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 void arch_cpu_idle_prepare(void)
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 2da5f3f9d345f..f7c42a7d09b66 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -124,7 +124,7 @@ void arch_cpu_idle(void)
 	 * tricks
 	 */
 	cpu_do_idle();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c
index f730869e21eed..69af6bc87e647 100644
--- a/arch/csky/kernel/process.c
+++ b/arch/csky/kernel/process.c
@@ -102,6 +102,6 @@ void arch_cpu_idle(void)
 #ifdef CONFIG_CPU_PM_STOP
 	asm volatile("stop\n");
 #endif
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 #endif
diff --git a/arch/h8300/kernel/process.c b/arch/h8300/kernel/process.c
index 83ce3caf73139..a2961c7b2332c 100644
--- a/arch/h8300/kernel/process.c
+++ b/arch/h8300/kernel/process.c
@@ -57,7 +57,7 @@ asmlinkage void ret_from_kernel_thread(void);
  */
 void arch_cpu_idle(void)
 {
-	local_irq_enable();
+	raw_local_irq_enable();
 	__asm__("sleep");
 }
 
diff --git a/arch/hexagon/kernel/process.c b/arch/hexagon/kernel/process.c
index dfd322c5ce83a..20962601a1b47 100644
--- a/arch/hexagon/kernel/process.c
+++ b/arch/hexagon/kernel/process.c
@@ -44,7 +44,7 @@ void arch_cpu_idle(void)
 {
 	__vmwait();
 	/*  interrupts wake us up, but irqs are still disabled */
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /*
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index f19cb97c00987..1b2769260688d 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -252,7 +252,7 @@ void arch_cpu_idle(void)
 	if (mark_idle)
 		(*mark_idle)(1);
 
-	safe_halt();
+	raw_safe_halt();
 
 	if (mark_idle)
 		(*mark_idle)(0);
diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c
index a9e46e525cd0a..f99860771ff48 100644
--- a/arch/microblaze/kernel/process.c
+++ b/arch/microblaze/kernel/process.c
@@ -149,5 +149,5 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs)
 
 void arch_cpu_idle(void)
 {
-       local_irq_enable();
+       raw_local_irq_enable();
 }
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
index 5bc3b04693c7d..18e69ebf5691d 100644
--- a/arch/mips/kernel/idle.c
+++ b/arch/mips/kernel/idle.c
@@ -33,19 +33,19 @@ static void __cpuidle r3081_wait(void)
 {
 	unsigned long cfg = read_c0_conf();
 	write_c0_conf(cfg | R30XX_CONF_HALT);
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 static void __cpuidle r39xx_wait(void)
 {
 	if (!need_resched())
 		write_c0_conf(read_c0_conf() | TX39_CONF_HALT);
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 void __cpuidle r4k_wait(void)
 {
-	local_irq_enable();
+	raw_local_irq_enable();
 	__r4k_wait();
 }
 
@@ -64,7 +64,7 @@ void __cpuidle r4k_wait_irqoff(void)
 		"	.set	arch=r4000	\n"
 		"	wait			\n"
 		"	.set	pop		\n");
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /*
@@ -84,7 +84,7 @@ static void __cpuidle rm7k_wait_irqoff(void)
 		"	wait						\n"
 		"	mtc0	$1, $12		# stalls until W stage	\n"
 		"	.set	pop					\n");
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /*
@@ -257,7 +257,7 @@ void arch_cpu_idle(void)
 	if (cpu_wait)
 		cpu_wait();
 	else
-		local_irq_enable();
+		raw_local_irq_enable();
 }
 
 #ifdef CONFIG_CPU_IDLE
diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c
index 88a4ec03edab4..f5cc55a88d310 100644
--- a/arch/nios2/kernel/process.c
+++ b/arch/nios2/kernel/process.c
@@ -33,7 +33,7 @@ EXPORT_SYMBOL(pm_power_off);
 
 void arch_cpu_idle(void)
 {
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /*
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
index 0ff391f00334c..3c98728cce249 100644
--- a/arch/openrisc/kernel/process.c
+++ b/arch/openrisc/kernel/process.c
@@ -79,7 +79,7 @@ void machine_power_off(void)
  */
 void arch_cpu_idle(void)
 {
-	local_irq_enable();
+	raw_local_irq_enable();
 	if (mfspr(SPR_UPR) & SPR_UPR_PMP)
 		mtspr(SPR_PMR, mfspr(SPR_PMR) | SPR_PMR_DME);
 }
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c
index f196d96e2f9f5..a92a23d6acd93 100644
--- a/arch/parisc/kernel/process.c
+++ b/arch/parisc/kernel/process.c
@@ -169,7 +169,7 @@ void __cpuidle arch_cpu_idle_dead(void)
 
 void __cpuidle arch_cpu_idle(void)
 {
-	local_irq_enable();
+	raw_local_irq_enable();
 
 	/* nop on real hardware, qemu will idle sleep. */
 	asm volatile("or %%r10,%%r10,%%r10\n":::);
diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index 422e31d2f5a2b..8df35f1329a42 100644
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -60,9 +60,9 @@ void arch_cpu_idle(void)
 		 * interrupts enabled, some don't.
 		 */
 		if (irqs_disabled())
-			local_irq_enable();
+			raw_local_irq_enable();
 	} else {
-		local_irq_enable();
+		raw_local_irq_enable();
 		/*
 		 * Go into low thread priority and possibly
 		 * low power mode.
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 2b97c493427c9..308e1d95ecbf0 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -36,7 +36,7 @@ extern asmlinkage void ret_from_kernel_thread(void);
 void arch_cpu_idle(void)
 {
 	wait_for_interrupt();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 void show_regs(struct pt_regs *regs)
diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c
index f7f1e64e0d980..2b85096964f84 100644
--- a/arch/s390/kernel/idle.c
+++ b/arch/s390/kernel/idle.c
@@ -33,10 +33,10 @@ void enabled_wait(void)
 		PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
 	clear_cpu_flag(CIF_NOHZ_DELAY);
 
-	local_irq_save(flags);
+	raw_local_irq_save(flags);
 	/* Call the assembler magic in entry.S */
 	psw_idle(idle, psw_mask);
-	local_irq_restore(flags);
+	raw_local_irq_restore(flags);
 
 	/* Account time spent with enabled wait psw loaded as idle time. */
 	raw_write_seqcount_begin(&idle->seqcount);
@@ -123,7 +123,7 @@ void arch_cpu_idle_enter(void)
 void arch_cpu_idle(void)
 {
 	enabled_wait();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 void arch_cpu_idle_exit(void)
diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c
index 0dc0f52f9bb8d..f59814983bd59 100644
--- a/arch/sh/kernel/idle.c
+++ b/arch/sh/kernel/idle.c
@@ -22,7 +22,7 @@ static void (*sh_idle)(void);
 void default_idle(void)
 {
 	set_bl_bit();
-	local_irq_enable();
+	raw_local_irq_enable();
 	/* Isn't this racy ? */
 	cpu_sleep();
 	clear_bl_bit();
diff --git a/arch/sparc/kernel/leon_pmc.c b/arch/sparc/kernel/leon_pmc.c
index 065e2d4b72908..396f46bca52eb 100644
--- a/arch/sparc/kernel/leon_pmc.c
+++ b/arch/sparc/kernel/leon_pmc.c
@@ -50,7 +50,7 @@ static void pmc_leon_idle_fixup(void)
 	register unsigned int address = (unsigned int)leon3_irqctrl_regs;
 
 	/* Interrupts need to be enabled to not hang the CPU */
-	local_irq_enable();
+	raw_local_irq_enable();
 
 	__asm__ __volatile__ (
 		"wr	%%g0, %%asr19\n"
@@ -66,7 +66,7 @@ static void pmc_leon_idle_fixup(void)
 static void pmc_leon_idle(void)
 {
 	/* Interrupts need to be enabled to not hang the CPU */
-	local_irq_enable();
+	raw_local_irq_enable();
 
 	/* For systems without power-down, this will be no-op */
 	__asm__ __volatile__ ("wr	%g0, %asr19\n\t");
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
index adfcaeab3ddc5..a023637359154 100644
--- a/arch/sparc/kernel/process_32.c
+++ b/arch/sparc/kernel/process_32.c
@@ -74,7 +74,7 @@ void arch_cpu_idle(void)
 {
 	if (sparc_idle)
 		(*sparc_idle)();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index a75093b993f9a..6f8c7822fc065 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -62,11 +62,11 @@ void arch_cpu_idle(void)
 {
 	if (tlb_type != hypervisor) {
 		touch_nmi_watchdog();
-		local_irq_enable();
+		raw_local_irq_enable();
 	} else {
 		unsigned long pstate;
 
-		local_irq_enable();
+		raw_local_irq_enable();
 
                 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
                  * the cpu sleep hypervisor call.
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 26b5e243d3fc0..495f101792b3d 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -217,7 +217,7 @@ void arch_cpu_idle(void)
 {
 	cpu_tasks[current_thread_info()->cpu].pid = os_getpid();
 	um_idle_sleep();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 int __cant_sleep(void) {
diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h
index e039a933aca3c..29dd27b5a339d 100644
--- a/arch/x86/include/asm/mwait.h
+++ b/arch/x86/include/asm/mwait.h
@@ -88,8 +88,6 @@ static inline void __mwaitx(unsigned long eax, unsigned long ebx,
 
 static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
 {
-	trace_hardirqs_on();
-
 	mds_idle_clear_cpu_buffers();
 	/* "mwait %eax, %ecx;" */
 	asm volatile("sti; .byte 0x0f, 0x01, 0xc9;"
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ba4593a913fab..145a7ac0c19aa 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -685,7 +685,7 @@ void arch_cpu_idle(void)
  */
 void __cpuidle default_idle(void)
 {
-	safe_halt();
+	raw_safe_halt();
 }
 #if defined(CONFIG_APM_MODULE) || defined(CONFIG_HALTPOLL_CPUIDLE_MODULE)
 EXPORT_SYMBOL(default_idle);
@@ -736,6 +736,8 @@ void stop_this_cpu(void *dummy)
 /*
  * AMD Erratum 400 aware idle routine. We handle it the same way as C3 power
  * states (local apic timer and TSC stop).
+ *
+ * XXX this function is completely buggered vs RCU and tracing.
  */
 static void amd_e400_idle(void)
 {
@@ -757,9 +759,9 @@ static void amd_e400_idle(void)
 	 * The switch back from broadcast mode needs to be called with
 	 * interrupts disabled.
 	 */
-	local_irq_disable();
+	raw_local_irq_disable();
 	tick_broadcast_exit();
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /*
@@ -801,9 +803,9 @@ static __cpuidle void mwait_idle(void)
 		if (!need_resched())
 			__sti_mwait(0, 0);
 		else
-			local_irq_enable();
+			raw_local_irq_enable();
 	} else {
-		local_irq_enable();
+		raw_local_irq_enable();
 	}
 	__current_clr_polling();
 }
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index f324dc36fc43d..dee807ffad11b 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -78,7 +78,7 @@ void __weak arch_cpu_idle_dead(void) { }
 void __weak arch_cpu_idle(void)
 {
 	cpu_idle_force_poll = 1;
-	local_irq_enable();
+	raw_local_irq_enable();
 }
 
 /**
@@ -94,9 +94,35 @@ void __cpuidle default_idle_call(void)
 
 		trace_cpu_idle(1, smp_processor_id());
 		stop_critical_timings();
+
+		/*
+		 * arch_cpu_idle() is supposed to enable IRQs, however
+		 * we can't do that because of RCU and tracing.
+		 *
+		 * Trace IRQs enable here, then switch off RCU, and have
+		 * arch_cpu_idle() use raw_local_irq_enable(). Note that
+		 * rcu_idle_enter() relies on lockdep IRQ state, so switch that
+		 * last -- this is very similar to the entry code.
+		 */
+		trace_hardirqs_on_prepare();
+		lockdep_hardirqs_on_prepare(_THIS_IP_);
 		rcu_idle_enter();
+		lockdep_hardirqs_on(_THIS_IP_);
+
 		arch_cpu_idle();
+
+		/*
+		 * OK, so IRQs are enabled here, but RCU needs them disabled to
+		 * turn itself back on.. funny thing is that disabling IRQs
+		 * will cause tracing, which needs RCU. Jump through hoops to
+		 * make it 'work'.
+		 */
+		raw_local_irq_disable();
+		lockdep_hardirqs_off(_THIS_IP_);
 		rcu_idle_exit();
+		lockdep_hardirqs_on(_THIS_IP_);
+		raw_local_irq_enable();
+
 		start_critical_timings();
 		trace_cpu_idle(PWR_EVENT_EXIT, smp_processor_id());
 	}
-- 
2.27.0

Re: [PATCH AUTOSEL 5.9 27/39] sched/idle: Fix arch_cpu_idle() vs tracing

[Heiko Carstens]

On Thu, Dec 03, 2020 at 08:28:21AM -0500, Sasha Levin wrote:
> From: Peter Zijlstra <peterz@infradead.org>
> 
> [ Upstream commit 58c644ba512cfbc2e39b758dd979edd1d6d00e27 ]
> 
> We call arch_cpu_idle() with RCU disabled, but then use
> local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
> 
> Switch all arch_cpu_idle() implementations to use
> raw_local_irq_{en,dis}able() and carefully manage the
> lockdep,rcu,tracing state like we do in entry.
> 
> (XXX: we really should change arch_cpu_idle() to not return with
> interrupts enabled)
> 
> Reported-by: Sven Schnelle <svens@linux.ibm.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Reviewed-by: Mark Rutland <mark.rutland@arm.com>
> Tested-by: Mark Rutland <mark.rutland@arm.com>
> Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
> Signed-off-by: Sasha Levin <sashal@kernel.org>

This patch broke s390 irq state tracing. A patch to fix this is
scheduled to be merged upstream today (hopefully).
Therefore I think this patch should not yet go into 5.9 stable.

Re: [PATCH AUTOSEL 5.9 27/39] sched/idle: Fix arch_cpu_idle() vs tracing

[Peter Zijlstra]

On Thu, Dec 03, 2020 at 03:54:42PM +0100, Heiko Carstens wrote:
> On Thu, Dec 03, 2020 at 08:28:21AM -0500, Sasha Levin wrote:
> > From: Peter Zijlstra <peterz@infradead.org>
> > 
> > [ Upstream commit 58c644ba512cfbc2e39b758dd979edd1d6d00e27 ]
> > 
> > We call arch_cpu_idle() with RCU disabled, but then use
> > local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
> > 
> > Switch all arch_cpu_idle() implementations to use
> > raw_local_irq_{en,dis}able() and carefully manage the
> > lockdep,rcu,tracing state like we do in entry.
> > 
> > (XXX: we really should change arch_cpu_idle() to not return with
> > interrupts enabled)
> > 
> > Reported-by: Sven Schnelle <svens@linux.ibm.com>
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > Reviewed-by: Mark Rutland <mark.rutland@arm.com>
> > Tested-by: Mark Rutland <mark.rutland@arm.com>
> > Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
> > Signed-off-by: Sasha Levin <sashal@kernel.org>
> 
> This patch broke s390 irq state tracing. A patch to fix this is
> scheduled to be merged upstream today (hopefully).
> Therefore I think this patch should not yet go into 5.9 stable.

Agreed.

Re: [PATCH AUTOSEL 5.9 27/39] sched/idle: Fix arch_cpu_idle() vs tracing

[Sasha Levin]

On Thu, Dec 03, 2020 at 06:10:15PM +0100, Peter Zijlstra wrote:
>On Thu, Dec 03, 2020 at 03:54:42PM +0100, Heiko Carstens wrote:
>> On Thu, Dec 03, 2020 at 08:28:21AM -0500, Sasha Levin wrote:
>> > From: Peter Zijlstra <peterz@infradead.org>
>> >
>> > [ Upstream commit 58c644ba512cfbc2e39b758dd979edd1d6d00e27 ]
>> >
>> > We call arch_cpu_idle() with RCU disabled, but then use
>> > local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
>> >
>> > Switch all arch_cpu_idle() implementations to use
>> > raw_local_irq_{en,dis}able() and carefully manage the
>> > lockdep,rcu,tracing state like we do in entry.
>> >
>> > (XXX: we really should change arch_cpu_idle() to not return with
>> > interrupts enabled)
>> >
>> > Reported-by: Sven Schnelle <svens@linux.ibm.com>
>> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
>> > Reviewed-by: Mark Rutland <mark.rutland@arm.com>
>> > Tested-by: Mark Rutland <mark.rutland@arm.com>
>> > Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
>> > Signed-off-by: Sasha Levin <sashal@kernel.org>
>>
>> This patch broke s390 irq state tracing. A patch to fix this is
>> scheduled to be merged upstream today (hopefully).
>> Therefore I think this patch should not yet go into 5.9 stable.
>
>Agreed.

I'll also grab b1cae1f84a0f ("s390: fix irq state tracing"). Thanks!

-- 
Thanks,
Sasha