| Message ID | 1397488277-14865-2-git-send-email-imammedo@redhat.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Mon, 2014-04-14 at 17:11 +0200, Igor Mammedov wrote: > currently if AP wake up is failed, master CPU marks AP as not present > in do_boot_cpu() by calling set_cpu_present(cpu, false). > That leads to following list corruption on the next physical CPU > hotplug: > > [ 418.107336] WARNING: CPU: 1 PID: 45 at lib/list_debug.c:33 __list_add+0xbe/0xd0() > [ 418.115268] list_add corruption. prev->next should be next (ffff88003dc57600), but was ffff88003e20c3a0. (prev=ffff88003e20c3a0). > [ 418.123693] Modules linked in: nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT ipt_REJECT cfg80211 xt_conntrack rfkill ee > [ 418.138979] CPU: 1 PID: 45 Comm: kworker/u10:1 Not tainted 3.14.0-rc6+ #387 > [ 418.149989] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007 > [ 418.165750] Workqueue: kacpi_hotplug acpi_hotplug_work_fn > [ 418.166433] 0000000000000021 ffff880038ca7988 ffffffff8159b22d 0000000000000021 > [ 418.176460] ffff880038ca79d8 ffff880038ca79c8 ffffffff8106942c ffff880038ca79e8 > [ 418.177453] ffff88003e20c3a0 ffff88003dc57600 ffff88003e20c3a0 00000000ffffffea > [ 418.178445] Call Trace: > [ 418.185811] [<ffffffff8159b22d>] dump_stack+0x49/0x5c > [ 418.186440] [<ffffffff8106942c>] warn_slowpath_common+0x8c/0xc0 > [ 418.187192] [<ffffffff81069516>] warn_slowpath_fmt+0x46/0x50 > [ 418.191231] [<ffffffff8136ef51>] ? acpi_ns_get_node+0xb7/0xc7 > [ 418.193889] [<ffffffff812f796e>] __list_add+0xbe/0xd0 > [ 418.196649] [<ffffffff812e2aa9>] kobject_add_internal+0x79/0x200 > [ 418.208610] [<ffffffff812e2e18>] kobject_add_varg+0x38/0x60 > [ 418.213831] [<ffffffff812e2ef4>] kobject_add+0x44/0x70 > [ 418.229961] [<ffffffff813e2c60>] device_add+0xd0/0x550 > [ 418.234991] [<ffffffff813f0e95>] ? pm_runtime_init+0xe5/0xf0 > [ 418.250226] [<ffffffff813e32be>] device_register+0x1e/0x30 > [ 418.255296] [<ffffffff813e82a3>] register_cpu+0xe3/0x130 > [ 418.266539] [<ffffffff81592be5>] arch_register_cpu+0x65/0x150 > [ 418.285845] [<ffffffff81355c0d>] acpi_processor_hotadd_init+0x5a/0x9b > ... > Which is caused by the fact that generic_processor_info() allocates > logical CPU id by calling: > > cpu = cpumask_next_zero(-1, cpu_present_mask); > > which returns id of previously failed to wake up CPU, since its bit > is cleared by do_boot_cpu() and as result register_cpu() tries to > register another CPU with the same id as already present but failed > to be onlined CPU. > > Taking in account that AP will not do anything if master CPU failed to > wake it up, there is no reason to mark that AP as not present and > break next cpu hotplug attempts. As a side effect of not marking AP > as not present, user would be allowed to online it again later. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> Hi Igor, Sorry for long delay... Can you please combine patch 1/5 and 2/5? When a CPU is marked as present, its APIC ID must be valid. So, it does not make sense to separate patch 1/5 and 2/5. With that change: Acked-by: Toshi Kani <toshi.kani@hp.com> Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 3482693..6124f15 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -860,7 +860,6 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle) /* was set by cpu_init() */ cpumask_clear_cpu(cpu, cpu_initialized_mask); - set_cpu_present(cpu, false); per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID; }
currently if AP wake up is failed, master CPU marks AP as not present in do_boot_cpu() by calling set_cpu_present(cpu, false). That leads to following list corruption on the next physical CPU hotplug: [ 418.107336] WARNING: CPU: 1 PID: 45 at lib/list_debug.c:33 __list_add+0xbe/0xd0() [ 418.115268] list_add corruption. prev->next should be next (ffff88003dc57600), but was ffff88003e20c3a0. (prev=ffff88003e20c3a0). [ 418.123693] Modules linked in: nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT ipt_REJECT cfg80211 xt_conntrack rfkill ee [ 418.138979] CPU: 1 PID: 45 Comm: kworker/u10:1 Not tainted 3.14.0-rc6+ #387 [ 418.149989] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007 [ 418.165750] Workqueue: kacpi_hotplug acpi_hotplug_work_fn [ 418.166433] 0000000000000021 ffff880038ca7988 ffffffff8159b22d 0000000000000021 [ 418.176460] ffff880038ca79d8 ffff880038ca79c8 ffffffff8106942c ffff880038ca79e8 [ 418.177453] ffff88003e20c3a0 ffff88003dc57600 ffff88003e20c3a0 00000000ffffffea [ 418.178445] Call Trace: [ 418.185811] [<ffffffff8159b22d>] dump_stack+0x49/0x5c [ 418.186440] [<ffffffff8106942c>] warn_slowpath_common+0x8c/0xc0 [ 418.187192] [<ffffffff81069516>] warn_slowpath_fmt+0x46/0x50 [ 418.191231] [<ffffffff8136ef51>] ? acpi_ns_get_node+0xb7/0xc7 [ 418.193889] [<ffffffff812f796e>] __list_add+0xbe/0xd0 [ 418.196649] [<ffffffff812e2aa9>] kobject_add_internal+0x79/0x200 [ 418.208610] [<ffffffff812e2e18>] kobject_add_varg+0x38/0x60 [ 418.213831] [<ffffffff812e2ef4>] kobject_add+0x44/0x70 [ 418.229961] [<ffffffff813e2c60>] device_add+0xd0/0x550 [ 418.234991] [<ffffffff813f0e95>] ? pm_runtime_init+0xe5/0xf0 [ 418.250226] [<ffffffff813e32be>] device_register+0x1e/0x30 [ 418.255296] [<ffffffff813e82a3>] register_cpu+0xe3/0x130 [ 418.266539] [<ffffffff81592be5>] arch_register_cpu+0x65/0x150 [ 418.285845] [<ffffffff81355c0d>] acpi_processor_hotadd_init+0x5a/0x9b ... Which is caused by the fact that generic_processor_info() allocates logical CPU id by calling: cpu = cpumask_next_zero(-1, cpu_present_mask); which returns id of previously failed to wake up CPU, since its bit is cleared by do_boot_cpu() and as result register_cpu() tries to register another CPU with the same id as already present but failed to be onlined CPU. Taking in account that AP will not do anything if master CPU failed to wake it up, there is no reason to mark that AP as not present and break next cpu hotplug attempts. As a side effect of not marking AP as not present, user would be allowed to online it again later. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- arch/x86/kernel/smpboot.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-)