From e1c105a9d75a1e9a44eb2f0b10204a6492057e4d Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Wed, 3 Aug 2016 13:22:28 -0400 Subject: [PATCH] hotplug: Prevent alloc/free of irq descriptors during cpu up/down (again) Now that Xen no longer allocates irqs in _cpu_up() we can restore commit a89941816726 ("hotplug: Prevent alloc/free of irq descriptors during cpu up/down") Signed-off-by: Boris Ostrovsky Acked-by: Thomas Gleixner CC: x86@kernel.org CC: Thomas Gleixner Signed-off-by: David Vrabel --- arch/x86/kernel/smpboot.c | 11 ----------- kernel/cpu.c | 8 ++++++++ 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 4296beb..26b473d 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1115,17 +1115,8 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle) common_cpu_up(cpu, tidle); - /* - * We have to walk the irq descriptors to setup the vector - * space for the cpu which comes online. Prevent irq - * alloc/free across the bringup. - */ - irq_lock_sparse(); - err = do_boot_cpu(apicid, cpu, tidle); - if (err) { - irq_unlock_sparse(); pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu); return -EIO; } @@ -1143,8 +1134,6 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle) touch_nmi_watchdog(); } - irq_unlock_sparse(); - return 0; } diff --git a/kernel/cpu.c b/kernel/cpu.c index 341bf80..ec12b72 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -349,8 +349,16 @@ static int bringup_cpu(unsigned int cpu) struct task_struct *idle = idle_thread_get(cpu); int ret; + /* + * Some architectures have to walk the irq descriptors to + * setup the vector space for the cpu which comes online. + * Prevent irq alloc/free across the bringup. + */ + irq_lock_sparse(); + /* Arch-specific enabling code. */ ret = __cpu_up(cpu, idle); + irq_unlock_sparse(); if (ret) { cpu_notify(CPU_UP_CANCELED, cpu); return ret; -- 2.7.4