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author | Ingo Molnar <mingo@elte.hu> | 2008-05-12 15:44:38 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2008-06-04 13:11:46 +0200 |
commit | deef325086c3897393b8f7d6bccd03405244fe18 (patch) | |
tree | cca203a04bcb1d0f0786fe393f67cc38f042126c | |
parent | fb3bbd6a663fe972611676381adc4c60ddfe61ac (diff) | |
download | blackbird-op-linux-deef325086c3897393b8f7d6bccd03405244fe18.tar.gz blackbird-op-linux-deef325086c3897393b8f7d6bccd03405244fe18.zip |
x86: disable preemption in native_smp_prepare_cpus
Priit Laes reported the following warning:
Call Trace:
[<ffffffff8022f1e1>] warn_on_slowpath+0x51/0x63
[<ffffffff80282e48>] sys_ioctl+0x2d/0x5d
[<ffffffff805185ff>] _spin_lock+0xe/0x24
[<ffffffff80227459>] task_rq_lock+0x3d/0x73
[<ffffffff805133c3>] set_cpu_sibling_map+0x336/0x350
[<ffffffff8021c1b8>] read_apic_id+0x30/0x62
[<ffffffff806d921d>] verify_local_APIC+0x90/0x138
[<ffffffff806d84b5>] native_smp_prepare_cpus+0x1f9/0x305
[<ffffffff806ce7b1>] kernel_init+0x59/0x2d9
[<ffffffff80518a26>] _spin_unlock_irq+0x11/0x2b
[<ffffffff8020bf48>] child_rip+0xa/0x12
[<ffffffff806ce758>] kernel_init+0x0/0x2d9
[<ffffffff8020bf3e>] child_rip+0x0/0x12
fix this by generally disabling preemption in native_smp_prepare_cpus().
Reported-and-bisected-by: Priit Laes <plaes@plaes.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r-- | arch/x86/kernel/smpboot.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 38988491c622..56078d61c793 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1190,6 +1190,7 @@ static void __init smp_cpu_index_default(void) */ void __init native_smp_prepare_cpus(unsigned int max_cpus) { + preempt_disable(); nmi_watchdog_default(); smp_cpu_index_default(); current_cpu_data = boot_cpu_data; @@ -1206,7 +1207,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) if (smp_sanity_check(max_cpus) < 0) { printk(KERN_INFO "SMP disabled\n"); disable_smp(); - return; + goto out; } preempt_disable(); @@ -1246,6 +1247,8 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) printk(KERN_INFO "CPU%d: ", 0); print_cpu_info(&cpu_data(0)); setup_boot_clock(); +out: + preempt_enable(); } /* * Early setup to make printk work. |