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* [PATCH AUTOSEL 5.12 20/80] sched/core: Initialize the idle task with preemption disabled
       [not found] <20210704230616.1489200-1-sashal@kernel.org>
@ 2021-07-04 23:05 ` Sasha Levin
  2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 22/80] crypto: nx - add missing MODULE_DEVICE_TABLE Sasha Levin
  2021-07-04 23:06 ` [PATCH AUTOSEL 5.12 65/80] KVM: PPC: Book3S HV: Fix TLB management on SMT8 POWER9 and POWER10 processors Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2021-07-04 23:05 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Sasha Levin, linux-s390, linux-arch, linux-ia64, linux-parisc,
	linux-sh, Peter Zijlstra, linux-xtensa, linux-mips, linux-csky,
	Ingo Molnar, openrisc, linux-alpha, sparclinux, linux-riscv,
	linux-snps-arc, linuxppc-dev, Valentin Schneider,
	linux-arm-kernel

From: Valentin Schneider <valentin.schneider@arm.com>

[ Upstream commit f1a0a376ca0c4ef1fc3d24e3e502acbb5b795674 ]

As pointed out by commit

  de9b8f5dcbd9 ("sched: Fix crash trying to dequeue/enqueue the idle thread")

init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.

As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().

Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().

Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().

Secondary startups were patched via coccinelle:

  @begone@
  @@

  -preempt_disable();
  ...
  cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/alpha/kernel/smp.c          | 1 -
 arch/arc/kernel/smp.c            | 1 -
 arch/arm/kernel/smp.c            | 1 -
 arch/arm64/include/asm/preempt.h | 2 +-
 arch/arm64/kernel/smp.c          | 1 -
 arch/csky/kernel/smp.c           | 1 -
 arch/ia64/kernel/smpboot.c       | 1 -
 arch/mips/kernel/smp.c           | 1 -
 arch/openrisc/kernel/smp.c       | 2 --
 arch/parisc/kernel/smp.c         | 1 -
 arch/powerpc/kernel/smp.c        | 1 -
 arch/riscv/kernel/smpboot.c      | 1 -
 arch/s390/include/asm/preempt.h  | 4 ++--
 arch/s390/kernel/smp.c           | 1 -
 arch/sh/kernel/smp.c             | 2 --
 arch/sparc/kernel/smp_32.c       | 1 -
 arch/sparc/kernel/smp_64.c       | 3 ---
 arch/x86/include/asm/preempt.h   | 2 +-
 arch/x86/kernel/smpboot.c        | 1 -
 arch/xtensa/kernel/smp.c         | 1 -
 include/asm-generic/preempt.h    | 2 +-
 init/main.c                      | 6 +-----
 kernel/fork.c                    | 2 +-
 kernel/sched/core.c              | 2 +-
 kernel/smpboot.c                 | 1 -
 25 files changed, 8 insertions(+), 34 deletions(-)

diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c
index f4dd9f3f3001..4b2575f936d4 100644
--- a/arch/alpha/kernel/smp.c
+++ b/arch/alpha/kernel/smp.c
@@ -166,7 +166,6 @@ smp_callin(void)
 	DBGS(("smp_callin: commencing CPU %d current %p active_mm %p\n",
 	      cpuid, current, current->active_mm));
 
-	preempt_disable();
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index 52906d314537..db0e104d6835 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -189,7 +189,6 @@ void start_kernel_secondary(void)
 	pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu);
 
 	local_irq_enable();
-	preempt_disable();
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 74679240a9d8..c7bb168b0d97 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -432,7 +432,6 @@ asmlinkage void secondary_start_kernel(void)
 #endif
 	pr_debug("CPU%u: Booted secondary processor\n", cpu);
 
-	preempt_disable();
 	trace_hardirqs_off();
 
 	/*
diff --git a/arch/arm64/include/asm/preempt.h b/arch/arm64/include/asm/preempt.h
index 80e946b2abee..e83f0982b99c 100644
--- a/arch/arm64/include/asm/preempt.h
+++ b/arch/arm64/include/asm/preempt.h
@@ -23,7 +23,7 @@ static inline void preempt_count_set(u64 pc)
 } while (0)
 
 #define init_idle_preempt_count(p, cpu) do { \
-	task_thread_info(p)->preempt_count = PREEMPT_ENABLED; \
+	task_thread_info(p)->preempt_count = PREEMPT_DISABLED; \
 } while (0)
 
 static inline void set_preempt_need_resched(void)
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 357590beaabb..48fd89256739 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -223,7 +223,6 @@ asmlinkage notrace void secondary_start_kernel(void)
 		init_gic_priority_masking();
 
 	rcu_cpu_starting(cpu);
-	preempt_disable();
 	trace_hardirqs_off();
 
 	/*
diff --git a/arch/csky/kernel/smp.c b/arch/csky/kernel/smp.c
index 0f9f5eef9338..e2993539af8e 100644
--- a/arch/csky/kernel/smp.c
+++ b/arch/csky/kernel/smp.c
@@ -281,7 +281,6 @@ void csky_start_secondary(void)
 	pr_info("CPU%u Online: %s...\n", cpu, __func__);
 
 	local_irq_enable();
-	preempt_disable();
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
 
diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c
index 49b488580939..d10f780c13b9 100644
--- a/arch/ia64/kernel/smpboot.c
+++ b/arch/ia64/kernel/smpboot.c
@@ -441,7 +441,6 @@ start_secondary (void *unused)
 #endif
 	efi_map_pal_code();
 	cpu_init();
-	preempt_disable();
 	smp_callin();
 
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index ef86fbad8546..d542fb7af3ba 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -348,7 +348,6 @@ asmlinkage void start_secondary(void)
 	 */
 
 	calibrate_delay();
-	preempt_disable();
 	cpu = smp_processor_id();
 	cpu_data[cpu].udelay_val = loops_per_jiffy;
 
diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
index 48e1092a64de..415e209732a3 100644
--- a/arch/openrisc/kernel/smp.c
+++ b/arch/openrisc/kernel/smp.c
@@ -145,8 +145,6 @@ asmlinkage __init void secondary_start_kernel(void)
 	set_cpu_online(cpu, true);
 
 	local_irq_enable();
-
-	preempt_disable();
 	/*
 	 * OK, it's off to the idle thread for us
 	 */
diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
index 10227f667c8a..1405b603b91b 100644
--- a/arch/parisc/kernel/smp.c
+++ b/arch/parisc/kernel/smp.c
@@ -302,7 +302,6 @@ void __init smp_callin(unsigned long pdce_proc)
 #endif
 
 	smp_cpu_init(slave_id);
-	preempt_disable();
 
 	flush_cache_all_local(); /* start with known state */
 	flush_tlb_all_local(NULL);
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index c2473e20f5f5..1d7daef1c3b6 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -1530,7 +1530,6 @@ void start_secondary(void *unused)
 	smp_store_cpu_info(cpu);
 	set_dec(tb_ticks_per_jiffy);
 	rcu_cpu_starting(cpu);
-	preempt_disable();
 	cpu_callin_map[cpu] = 1;
 
 	if (smp_ops->setup_cpu)
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 5e276c25646f..1941a6ce86a1 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -176,7 +176,6 @@ asmlinkage __visible void smp_callin(void)
 	 * Disable preemption before enabling interrupts, so we don't try to
 	 * schedule a CPU that hasn't actually started yet.
 	 */
-	preempt_disable();
 	local_irq_enable();
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
diff --git a/arch/s390/include/asm/preempt.h b/arch/s390/include/asm/preempt.h
index b49e0492842c..23ff51be7e29 100644
--- a/arch/s390/include/asm/preempt.h
+++ b/arch/s390/include/asm/preempt.h
@@ -32,7 +32,7 @@ static inline void preempt_count_set(int pc)
 #define init_task_preempt_count(p)	do { } while (0)
 
 #define init_idle_preempt_count(p, cpu)	do { \
-	S390_lowcore.preempt_count = PREEMPT_ENABLED; \
+	S390_lowcore.preempt_count = PREEMPT_DISABLED; \
 } while (0)
 
 static inline void set_preempt_need_resched(void)
@@ -91,7 +91,7 @@ static inline void preempt_count_set(int pc)
 #define init_task_preempt_count(p)	do { } while (0)
 
 #define init_idle_preempt_count(p, cpu)	do { \
-	S390_lowcore.preempt_count = PREEMPT_ENABLED; \
+	S390_lowcore.preempt_count = PREEMPT_DISABLED; \
 } while (0)
 
 static inline void set_preempt_need_resched(void)
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 58c8afa3da65..d60c7374d807 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -877,7 +877,6 @@ static void smp_init_secondary(void)
 	restore_access_regs(S390_lowcore.access_regs_save_area);
 	cpu_init();
 	rcu_cpu_starting(cpu);
-	preempt_disable();
 	init_cpu_timer();
 	vtime_init();
 	vdso_getcpu_init();
diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c
index 372acdc9033e..65924d9ec245 100644
--- a/arch/sh/kernel/smp.c
+++ b/arch/sh/kernel/smp.c
@@ -186,8 +186,6 @@ asmlinkage void start_secondary(void)
 
 	per_cpu_trap_init();
 
-	preempt_disable();
-
 	notify_cpu_starting(cpu);
 
 	local_irq_enable();
diff --git a/arch/sparc/kernel/smp_32.c b/arch/sparc/kernel/smp_32.c
index 50c127ab46d5..22b148e5a5f8 100644
--- a/arch/sparc/kernel/smp_32.c
+++ b/arch/sparc/kernel/smp_32.c
@@ -348,7 +348,6 @@ static void sparc_start_secondary(void *arg)
 	 */
 	arch_cpu_pre_starting(arg);
 
-	preempt_disable();
 	cpu = smp_processor_id();
 
 	notify_cpu_starting(cpu);
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
index e38d8bf454e8..ae5faa1d989d 100644
--- a/arch/sparc/kernel/smp_64.c
+++ b/arch/sparc/kernel/smp_64.c
@@ -138,9 +138,6 @@ void smp_callin(void)
 
 	set_cpu_online(cpuid, true);
 
-	/* idle thread is expected to have preempt disabled */
-	preempt_disable();
-
 	local_irq_enable();
 
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index f8cb8af4de5c..fe5efbcba824 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -44,7 +44,7 @@ static __always_inline void preempt_count_set(int pc)
 #define init_task_preempt_count(p) do { } while (0)
 
 #define init_idle_preempt_count(p, cpu) do { \
-	per_cpu(__preempt_count, (cpu)) = PREEMPT_ENABLED; \
+	per_cpu(__preempt_count, (cpu)) = PREEMPT_DISABLED; \
 } while (0)
 
 /*
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 363b36bbd791..ebc4b13b74a4 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -236,7 +236,6 @@ static void notrace start_secondary(void *unused)
 	cpu_init();
 	rcu_cpu_starting(raw_smp_processor_id());
 	x86_cpuinit.early_percpu_clock_init();
-	preempt_disable();
 	smp_callin();
 
 	enable_start_cpu0 = 0;
diff --git a/arch/xtensa/kernel/smp.c b/arch/xtensa/kernel/smp.c
index cd85a7a2722b..1254da07ead1 100644
--- a/arch/xtensa/kernel/smp.c
+++ b/arch/xtensa/kernel/smp.c
@@ -145,7 +145,6 @@ void secondary_start_kernel(void)
 	cpumask_set_cpu(cpu, mm_cpumask(mm));
 	enter_lazy_tlb(mm, current);
 
-	preempt_disable();
 	trace_hardirqs_off();
 
 	calibrate_delay();
diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h
index d683f5e6d791..b4d43a4af5f7 100644
--- a/include/asm-generic/preempt.h
+++ b/include/asm-generic/preempt.h
@@ -29,7 +29,7 @@ static __always_inline void preempt_count_set(int pc)
 } while (0)
 
 #define init_idle_preempt_count(p, cpu) do { \
-	task_thread_info(p)->preempt_count = PREEMPT_ENABLED; \
+	task_thread_info(p)->preempt_count = PREEMPT_DISABLED; \
 } while (0)
 
 static __always_inline void set_preempt_need_resched(void)
diff --git a/init/main.c b/init/main.c
index 5bd1a25f1d6f..c97d3c0247a1 100644
--- a/init/main.c
+++ b/init/main.c
@@ -918,11 +918,7 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 	 * time - but meanwhile we still have a functioning scheduler.
 	 */
 	sched_init();
-	/*
-	 * Disable preemption - early bootup scheduling is extremely
-	 * fragile until we cpu_idle() for the first time.
-	 */
-	preempt_disable();
+
 	if (WARN(!irqs_disabled(),
 		 "Interrupts were enabled *very* early, fixing it\n"))
 		local_irq_disable();
diff --git a/kernel/fork.c b/kernel/fork.c
index 321a5e31d817..2654a5a9e5df 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2405,7 +2405,7 @@ static inline void init_idle_pids(struct task_struct *idle)
 	}
 }
 
-struct task_struct *fork_idle(int cpu)
+struct task_struct * __init fork_idle(int cpu)
 {
 	struct task_struct *task;
 	struct kernel_clone_args args = {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 814200541f8f..e25b2d8ec18d 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7428,7 +7428,7 @@ void show_state_filter(unsigned long state_filter)
  * NOTE: this function does not set the idle thread's NEED_RESCHED
  * flag, to make booting more robust.
  */
-void init_idle(struct task_struct *idle, int cpu)
+void __init init_idle(struct task_struct *idle, int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index f25208e8df83..e4163042c4d6 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -33,7 +33,6 @@ struct task_struct *idle_thread_get(unsigned int cpu)
 
 	if (!tsk)
 		return ERR_PTR(-ENOMEM);
-	init_idle(tsk, cpu);
 	return tsk;
 }
 
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH AUTOSEL 5.12 22/80] crypto: nx - add missing MODULE_DEVICE_TABLE
       [not found] <20210704230616.1489200-1-sashal@kernel.org>
  2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 20/80] sched/core: Initialize the idle task with preemption disabled Sasha Levin
@ 2021-07-04 23:05 ` Sasha Levin
  2021-07-04 23:06 ` [PATCH AUTOSEL 5.12 65/80] KVM: PPC: Book3S HV: Fix TLB management on SMT8 POWER9 and POWER10 processors Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2021-07-04 23:05 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Sasha Levin, Herbert Xu, Hulk Robot, Bixuan Cui, linux-crypto,
	linuxppc-dev

From: Bixuan Cui <cuibixuan@huawei.com>

[ Upstream commit 06676aa1f455c74e3ad1624cea3acb9ed2ef71ae ]

This patch adds missing MODULE_DEVICE_TABLE definition which generates
correct modalias for automatic loading of this driver when it is built
as an external module.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/crypto/nx/nx-842-pseries.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/crypto/nx/nx-842-pseries.c b/drivers/crypto/nx/nx-842-pseries.c
index cc8dd3072b8b..8ee547ee378e 100644
--- a/drivers/crypto/nx/nx-842-pseries.c
+++ b/drivers/crypto/nx/nx-842-pseries.c
@@ -1069,6 +1069,7 @@ static const struct vio_device_id nx842_vio_driver_ids[] = {
 	{"ibm,compression-v1", "ibm,compression"},
 	{"", ""},
 };
+MODULE_DEVICE_TABLE(vio, nx842_vio_driver_ids);
 
 static struct vio_driver nx842_vio_driver = {
 	.name = KBUILD_MODNAME,
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH AUTOSEL 5.12 65/80] KVM: PPC: Book3S HV: Fix TLB management on SMT8 POWER9 and POWER10 processors
       [not found] <20210704230616.1489200-1-sashal@kernel.org>
  2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 20/80] sched/core: Initialize the idle task with preemption disabled Sasha Levin
  2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 22/80] crypto: nx - add missing MODULE_DEVICE_TABLE Sasha Levin
@ 2021-07-04 23:06 ` Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2021-07-04 23:06 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Sasha Levin, Fabiano Rosas, Nicholas Piggin, kvm-ppc,
	Suraj Jitindar Singh, linuxppc-dev

From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

[ Upstream commit 77bbbc0cf84834ed130838f7ac1988567f4d0288 ]

The POWER9 vCPU TLB management code assumes all threads in a core share
a TLB, and that TLBIEL execued by one thread will invalidate TLBs for
all threads. This is not the case for SMT8 capable POWER9 and POWER10
(big core) processors, where the TLB is split between groups of threads.
This results in TLB multi-hits, random data corruption, etc.

Fix this by introducing cpu_first_tlb_thread_sibling etc., to determine
which siblings share TLBs, and use that in the guest TLB flushing code.

[npiggin@gmail.com: add changelog and comment]

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210602040441.3984352-1-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/include/asm/cputhreads.h | 30 +++++++++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv.c          | 13 ++++++------
 arch/powerpc/kvm/book3s_hv_builtin.c  |  2 +-
 arch/powerpc/kvm/book3s_hv_rm_mmu.c   |  2 +-
 4 files changed, 39 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/include/asm/cputhreads.h b/arch/powerpc/include/asm/cputhreads.h
index 98c8bd155bf9..b167186aaee4 100644
--- a/arch/powerpc/include/asm/cputhreads.h
+++ b/arch/powerpc/include/asm/cputhreads.h
@@ -98,6 +98,36 @@ static inline int cpu_last_thread_sibling(int cpu)
 	return cpu | (threads_per_core - 1);
 }
 
+/*
+ * tlb_thread_siblings are siblings which share a TLB. This is not
+ * architected, is not something a hypervisor could emulate and a future
+ * CPU may change behaviour even in compat mode, so this should only be
+ * used on PowerNV, and only with care.
+ */
+static inline int cpu_first_tlb_thread_sibling(int cpu)
+{
+	if (cpu_has_feature(CPU_FTR_ARCH_300) && (threads_per_core == 8))
+		return cpu & ~0x6;	/* Big Core */
+	else
+		return cpu_first_thread_sibling(cpu);
+}
+
+static inline int cpu_last_tlb_thread_sibling(int cpu)
+{
+	if (cpu_has_feature(CPU_FTR_ARCH_300) && (threads_per_core == 8))
+		return cpu | 0x6;	/* Big Core */
+	else
+		return cpu_last_thread_sibling(cpu);
+}
+
+static inline int cpu_tlb_thread_sibling_step(void)
+{
+	if (cpu_has_feature(CPU_FTR_ARCH_300) && (threads_per_core == 8))
+		return 2;		/* Big Core */
+	else
+		return 1;
+}
+
 static inline u32 get_tensr(void)
 {
 #ifdef	CONFIG_BOOKE
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 60c5bc0c130c..1c6e0a52fb53 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2619,7 +2619,7 @@ static void radix_flush_cpu(struct kvm *kvm, int cpu, struct kvm_vcpu *vcpu)
 	cpumask_t *cpu_in_guest;
 	int i;
 
-	cpu = cpu_first_thread_sibling(cpu);
+	cpu = cpu_first_tlb_thread_sibling(cpu);
 	if (nested) {
 		cpumask_set_cpu(cpu, &nested->need_tlb_flush);
 		cpu_in_guest = &nested->cpu_in_guest;
@@ -2633,9 +2633,10 @@ static void radix_flush_cpu(struct kvm *kvm, int cpu, struct kvm_vcpu *vcpu)
 	 * the other side is the first smp_mb() in kvmppc_run_core().
 	 */
 	smp_mb();
-	for (i = 0; i < threads_per_core; ++i)
-		if (cpumask_test_cpu(cpu + i, cpu_in_guest))
-			smp_call_function_single(cpu + i, do_nothing, NULL, 1);
+	for (i = cpu; i <= cpu_last_tlb_thread_sibling(cpu);
+					i += cpu_tlb_thread_sibling_step())
+		if (cpumask_test_cpu(i, cpu_in_guest))
+			smp_call_function_single(i, do_nothing, NULL, 1);
 }
 
 static void kvmppc_prepare_radix_vcpu(struct kvm_vcpu *vcpu, int pcpu)
@@ -2666,8 +2667,8 @@ static void kvmppc_prepare_radix_vcpu(struct kvm_vcpu *vcpu, int pcpu)
 	 */
 	if (prev_cpu != pcpu) {
 		if (prev_cpu >= 0 &&
-		    cpu_first_thread_sibling(prev_cpu) !=
-		    cpu_first_thread_sibling(pcpu))
+		    cpu_first_tlb_thread_sibling(prev_cpu) !=
+		    cpu_first_tlb_thread_sibling(pcpu))
 			radix_flush_cpu(kvm, prev_cpu, vcpu);
 		if (nested)
 			nested->prev_cpu[vcpu->arch.nested_vcpu_id] = pcpu;
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 158d309b42a3..b5e5d07cb40f 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -797,7 +797,7 @@ void kvmppc_check_need_tlb_flush(struct kvm *kvm, int pcpu,
 	 * Thus we make all 4 threads use the same bit.
 	 */
 	if (cpu_has_feature(CPU_FTR_ARCH_300))
-		pcpu = cpu_first_thread_sibling(pcpu);
+		pcpu = cpu_first_tlb_thread_sibling(pcpu);
 
 	if (nested)
 		need_tlb_flush = &nested->need_tlb_flush;
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 88da2764c1bb..3ddc83d2e849 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -67,7 +67,7 @@ static int global_invalidates(struct kvm *kvm)
 		 * so use the bit for the first thread to represent the core.
 		 */
 		if (cpu_has_feature(CPU_FTR_ARCH_300))
-			cpu = cpu_first_thread_sibling(cpu);
+			cpu = cpu_first_tlb_thread_sibling(cpu);
 		cpumask_clear_cpu(cpu, &kvm->arch.need_tlb_flush);
 	}
 
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-07-04 23:08 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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     [not found] <20210704230616.1489200-1-sashal@kernel.org>
2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 20/80] sched/core: Initialize the idle task with preemption disabled Sasha Levin
2021-07-04 23:05 ` [PATCH AUTOSEL 5.12 22/80] crypto: nx - add missing MODULE_DEVICE_TABLE Sasha Levin
2021-07-04 23:06 ` [PATCH AUTOSEL 5.12 65/80] KVM: PPC: Book3S HV: Fix TLB management on SMT8 POWER9 and POWER10 processors Sasha Levin

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