Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964990AbVJUPqn (ORCPT ); Fri, 21 Oct 2005 11:46:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964992AbVJUPqn (ORCPT ); Fri, 21 Oct 2005 11:46:43 -0400 Received: from ms-smtp-02.nyroc.rr.com ([24.24.2.56]:34293 "EHLO ms-smtp-02.nyroc.rr.com") by vger.kernel.org with ESMTP id S964990AbVJUPqm (ORCPT ); Fri, 21 Oct 2005 11:46:42 -0400 Date: Fri, 21 Oct 2005 11:46:32 -0400 (EDT) From: Steven Rostedt X-X-Sender: rostedt@localhost.localdomain To: Thomas Gleixner cc: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: False positive (well not really) on RT backward clock check In-Reply-To: <1129902741.15748.4.camel@tglx.tec.linutronix.de> Message-ID: References: <1129902741.15748.4.camel@tglx.tec.linutronix.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10126 Lines: 213 On Fri, 21 Oct 2005, Thomas Gleixner wrote: > On Fri, 2005-10-21 at 09:45 -0400, Steven Rostedt wrote: > > Ingo, > > > > Just want to let you know that I got the warning of the clock going > > backwards on boot up. But it happened right after I got this message. > > > > Ktimers: Switched to high resolution mode CPU 0 > > > > So I'm assuming that the clock can go backwards by the switch to high res > > timers. > > Can you provide the boot messages up to the switch please ? It's more > likely that this is the switch of the clocksource from jiffies to TSC. > The ktimers high res switch is done in this context. > I think you're right about that. Here it is. Sorry for the late reply. The original was from my custom kernel and I wanted to get an output from Ingo's. This is rc5-rt1. -- Steve Linux version 2.6.14-rc5-rt1 (root@rtsmp) (gcc version 3.3.5 (Debian 1:3.3.5-13)) #1 SMP PREEMPT Fri Oct 21 14:36:19 CEST 2005 BIOS-provided physical RAM map: BIOS-e820: 0000000000000000 - 0000000000099c00 (usable) BIOS-e820: 0000000000099c00 - 00000000000a0000 (reserved) BIOS-e820: 00000000000ca000 - 00000000000d0000 (reserved) BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 000000001fef0000 (usable) BIOS-e820: 000000001fef0000 - 000000001feff000 (ACPI data) BIOS-e820: 000000001feff000 - 000000001ff00000 (ACPI NVS) BIOS-e820: 000000001ff00000 - 0000000020000000 (usable) BIOS-e820: 00000000fec00000 - 00000000fed00000 (reserved) BIOS-e820: 00000000fee00000 - 00000000fef00000 (reserved) BIOS-e820: 00000000ffc00000 - 0000000100000000 (reserved) 512MB LOWMEM available. found SMP MP-table at 000f6a90 On node 0 totalpages: 131072 DMA zone: 4096 pages, LIFO batch:1 Normal zone: 126976 pages, LIFO batch:31 HighMem zone: 0 pages, LIFO batch:1 early console enabled DMI present. ACPI: RSDP (v000 PTLTD ) @ 0x000f6a20 ACPI: RSDT (v001 PTLTD RSDT 0x06040001 LTP 0x00000000) @ 0x1fefbd7d ACPI: FADT (v001 FSC D1309 0x06040001 0x000f4240) @ 0x1fefbdb1 ACPI: SPCR (v001 PTLTD $UCRTBL$ 0x06040001 PTL 0x00000001) @ 0x1fefeef8 ACPI: MADT (v001 PTLTD APIC 0x06040001 LTP 0x00000000) @ 0x1fefef48 ACPI: BOOT (v001 PTLTD $SBFTBL$ 0x06040001 LTP 0x00000001) @ 0x1fefefd8 ACPI: DSDT (v001 FSC D1204 0x06040001 MSFT 0x0100000e) @ 0x00000000 ACPI: Local APIC address 0xfee00000 ACPI: LAPIC (acpi_id[0x00] lapic_id[0x06] enabled) Processor #6 15:2 APIC version 20 ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled) Processor #0 15:2 APIC version 20 ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled) Processor #1 15:2 APIC version 20 WARNING: maxcpus limit of 2 reached. Processor ignored. ACPI: LAPIC (acpi_id[0x03] lapic_id[0x07] enabled) Processor #7 15:2 APIC version 20 WARNING: maxcpus limit of 2 reached. Processor ignored. ACPI: LAPIC_NMI (acpi_id[0x00] high edge lint[0x1]) ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1]) ACPI: LAPIC_NMI (acpi_id[0x02] high edge lint[0x1]) ACPI: LAPIC_NMI (acpi_id[0x03] high edge lint[0x1]) ACPI: IOAPIC (id[0x02] address[0xfec00000] gsi_base[0]) mapped IOAPIC to ffffc000 (fec00000) IOAPIC[0]: apic_id 2, version 17, address 0xfec00000, GSI 0-15 ACPI: IOAPIC (id[0x03] address[0xfec10000] gsi_base[16]) mapped IOAPIC to ffffb000 (fec10000) IOAPIC[1]: apic_id 3, version 17, address 0xfec10000, GSI 16-31 ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 high edge) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) ACPI: IRQ0 used by override. ACPI: IRQ2 used by override. ACPI: IRQ9 used by override. Enabling APIC mode: Flat. Using 2 I/O APICs Using ACPI (MADT) for SMP configuration information Allocating PCI resources starting at 30000000 (gap: 20000000:dec00000) Detected 2395.544 MHz processor. Real-Time Preemption Support (C) 2004-2005 Ingo Molnar Built 1 zonelists Kernel command line: root=/dev/sda1 ro console=ttyS0,115200 console=tty0 nmi_watchdog=2 earlyprintk=ttyS0,115200 maxcpus=2 panic=30 mapped APIC to ffffd000 (fee00000) Initializing CPU#0 WARNING: experimental RCU implementation. PID hash table entries: 4096 (order: 12, 65536 bytes) Event source pit installed with caps set: 01 disabling early console Console: colour VGA+ 80x25 Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) Memory: 508724k/524288k available (2136k kernel code, 15088k reserved, 712k data, 212k init, 0k highmem) Checking if this processor honours the WP bit even in supervisor mode... Ok. Calibrating delay using timer specific routine.. 4793.28 BogoMIPS (lpj=2396641) Security Framework v1.0.0 initialized SELinux: Disabled at boot. Mount-cache hash table entries: 512 CPU: After generic identify, caps: bfebfbff 00000000 00000000 00000000 00004400 00000000 00000000 CPU: After vendor identify, caps: bfebfbff 00000000 00000000 00000000 00004400 00000000 00000000 CPU: Trace cache: 12K uops, L1 D cache: 8K CPU: L2 cache: 512K CPU: Physical Processor ID: 3 CPU: After all inits, caps: bfebfbff 00000000 00000000 00000080 00004400 00000000 00000000 Intel machine check architecture supported. Intel machine check reporting enabled on CPU#0. CPU0: Intel P4/Xeon Extended MCE MSRs (12) available CPU0: Thermal monitoring handled by SMI mtrr: v2.0 (20020519) Enabling fast FPU save and restore... done. Enabling unmasked SIMD FPU exception support... done. Checking 'hlt' instruction... OK. CPU0: Intel(R) Xeon(TM) CPU 2.40GHz stepping 07 Booting processor 1/0 eip 2000 Initializing CPU#1 Calibrating delay using timer specific routine.. 4790.12 BogoMIPS (lpj=2395061) CPU: After generic identify, caps: bfebfbff 00000000 00000000 00000000 00004400 00000000 00000000 CPU: After vendor identify, caps: bfebfbff 00000000 00000000 00000000 00004400 00000000 00000000 CPU: Trace cache: 12K uops, L1 D cache: 8K CPU: L2 cache: 512K CPU: Physical Processor ID: 0 CPU: After all inits, caps: bfebfbff 00000000 00000000 00000080 00004400 00000000 00000000 Intel machine check architecture supported. Intel machine check reporting enabled on CPU#1. CPU1: Intel P4/Xeon Extended MCE MSRs (12) available CPU1: Thermal monitoring enabled CPU1: Intel(R) Xeon(TM) CPU 2.40GHz stepping 07 Total of 2 processors activated (9583.40 BogoMIPS). ENABLING IO-APIC IRQs ..TIMER: vector=0x31 pin1=2 pin2=-1 Event source lapic installed with caps set: 06 checking TSC synchronization across 2 CPUs: passed. softlockup thread 0 started up. Event source lapic installed with caps set: 06 Brought up 2 CPUs softlockup thread 1 started up. NET: Registered protocol family 16 ACPI: bus type pci registered PCI: PCI BIOS revision 2.10 entry at 0xfda31, last bus=2 PCI: Using configuration type 1 ACPI: Subsystem revision 20050902 ACPI: Interpreter enabled ACPI: Using IOAPIC for interrupt routing ACPI: PCI Root Bridge [PCI0] (0000:00) PCI: Probing PCI hardware (bus 00) Boot video device is 0000:00:04.0 PCI: Ignoring BAR0-3 of IDE controller 0000:00:0f.1 ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKC] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKE] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKF] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKG] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKH] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKI] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKJ] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKK] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKL] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: PCI Interrupt Link [LNKM] (IRQs 3 4 5 6 7 *9 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKN] (IRQs 3 4 *5 6 7 9 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKO] (IRQs 3 4 5 6 7 9 10 *11 12 14 15) ACPI: PCI Interrupt Link [LNKP] (IRQs 3 4 5 6 7 9 10 11 12 14 15) *0, disabled. ACPI: Device [ECP] status [00000008]: functional but not present; setting present ACPI: PCI Root Bridge [PCIA] (0000:01) PCI: Probing PCI hardware (bus 01) ACPI: PCI Interrupt Routing Table [\_SB_.PCIA._PRT] ACPI: PCI Root Bridge [PCIB] (0000:02) PCI: Probing PCI hardware (bus 02) ACPI: PCI Interrupt Routing Table [\_SB_.PCIB._PRT] Linux Plug and Play Support v0.97 (c) Adam Belay pnp: PnP ACPI init pnp: PnP ACPI: found 12 devices PnPBIOS: Disabled by ACPI PNP SCSI subsystem initialized PCI: Using ACPI for IRQ routing PCI: If a device doesn't work, try "pci=routeirq". If it helps, post a report Simple Boot Flag at 0x69 set to 0x1 VFS: Disk quotas dquot_6.5.1 Dquot-cache hash table entries: 1024 (order 0, 4096 bytes) Initializing Cryptographic API isapnp: Scanning for PnP cards... Time: tsc clocksource has been installed. WARNING: non-monotonic time! Ktimers: Switched to high resolution mode CPU 0 softirq-timer/1/14[CPU#1]: BUG in ktime_get at kernel/ktimers.c:101 [] dump_stack+0x23/0x30 (20) [] __WARN_ON+0x67/0x80 (44) [] ktime_get+0xd2/0x100 (48) [] ktimer_run_queues+0x56/0x130 (60) [] run_timer_softirq+0x12e/0x450 (56) [] ksoftirqd+0x120/0x1a0 (40) [] kthread+0xbb/0xc0 (48) [] kernel_thread_helper+0x5/0x10 (538427420) --------------------------- | preempt count: 00000001 ] | 1-level deep critical section nesting: ---------------------------------------- .. [] .... add_preempt_count+0x1c/0x20 .....[] .. ( <= __WARN_ON+0x1b/0x80) Ktimers: Switched to high resolution mode CPU 1 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/