From 0e81cb59c7120191c0243c686b591797bc79e5c6 Mon Sep 17 00:00:00 2001 From: Alok Kataria Date: Tue, 10 Feb 2009 16:45:37 -0800 Subject: [PATCH] x86, apic: fix initialization of wakeup_cpu With refactoring of wake_cpu macros the 32bit code in tip doesn't execute generic_apic_probe if CONFIG_X86_32_NON_STANDARD is not set. Even on a x86 STANDARD cpu we need to execute the generic_apic_probe function, as we rely on this function to execute the update_genapic quirk which initilizes apic->wakeup_cpu. Failing to do so results in we making a call to a null function in do_boot_cpu. The stack trace without the patch goes like this. Booting processor 1 APIC 0x1 ip 0x6000 BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<(null)>] (null) *pdpt = 0000000000839001 *pde = 0000000000c97067 *pte = 0000000000000163 Oops: 0000 [#1] SMP last sysfs file: Modules linked in: Pid: 1, comm: swapper Not tainted (2.6.29-rc4-tip #18) VMware Virtual Platform EIP: 0062:[<00000000>] EFLAGS: 00010293 CPU: 0 EIP is at 0x0 EAX: 00000001 EBX: 00006000 ECX: c077ed00 EDX: 00006000 ESI: 00000001 EDI: 00000001 EBP: ef04cf40 ESP: ef04cf1c DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 006a Process swapper (pid: 1, ti=ef04c000 task=ef050000 task.ti=ef04c000) Stack: c0644e52 00000000 ef04cf24 ef04cf24 c064468d c0886dc0 00000000 c0702aea ef055480 00000001 00000101 dead4ead ffffffff ffffffff c08af530 00000000 c0709715 ef04cf60 ef04cf60 00000001 00000000 00000000 dead4ead ffffffff Call Trace: [] ? native_cpu_up+0x2de/0x45b [] ? do_fork_idle+0x0/0x19 [] ? _cpu_up+0x88/0xe8 [] ? cpu_up+0x42/0x4e [] ? kernel_init+0x99/0x14b [] ? kernel_init+0x0/0x14b [] ? kernel_thread_helper+0x7/0x10 Code: Bad EIP value. EIP: [<00000000>] 0x0 SS:ESP 006a:ef04cf1c I think we should call generic_apic_probe unconditionally for 32 bit now. Signed-off-by: Alok N Kataria Acked-by: Yinghai Lu Signed-off-by: Ingo Molnar --- arch/x86/kernel/setup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 8d8fa992c9a..150e6d0a3b4 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -936,7 +936,7 @@ void __init setup_arch(char **cmdline_p) map_vsyscall(); #endif -#if defined(CONFIG_X86_32_NON_STANDARD) || defined(CONFIG_X86_BIGSMP) +#ifdef CONFIG_X86_32 generic_apic_probe(); #endif -- 2.20.1