"APIC error on CPUx" - what does this mean?
Quoted 8 lines · Chris Wedgwood
On Mon, Jan 07, 2002 at 01:29:42PM +0100, Petr Vandrovec wrote:
They are spurious IRQ 7, just message is printed only once during kernel lifetime... I have about three spurious IRQ 7 per each 1000 interrupts delivered to CPU. It is on A7V (Via KT133).
Any idea _why_ these occur though? It seems some mainboards produce a plethora of these whilst others never produce these...
Nope. Probably when CPU is in local APIC mode, it acknowledges interrupts to chipset with different timming, and from time to time CPU still sees IRQ pending, so it asks for vector, but as chipset has no interrupt pending, it answers with IRQ7. I did no analysis to find whether IRQ7 happens directly when we send confirmation to 8259, or whether it happens due to some noise on IRQ line.
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
Best regards,
Petr Vandrovec [email protected]
Quoted 5 lines
whether IRQ7 happens directly when we send confirmation to 8259, or whether it happens due to some noise on IRQ line.
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
Are you using an AMD northbridge and VIA southbridge together ?
On Mon, Jan 07, 2002 at 02:16:28PM +0100, Petr Vandrovec wrote:
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
I have a dual P3 (VIA based) that does emits the Spurious Int7 message shortly after boot (I've never checked /proc/interrupts though) whereas my ServerWorks chipset never does this.
--cw
----- Original Message -----
From: "Petr Vandrovec" <[email protected]>
To: "Chris Wedgwood" <[email protected]>
Cc: <[email protected]>; "Linux Kernel Mailing List" <[email protected]>; <[email protected]>
Sent: Monday, January 07, 2002 2:16 PM
Subject: Re: "APIC error on CPUx" - what does this mean?
Quoted 17 lines · Chris Wedgwood
Quoted 8 lines · Petr Vandrovec
They are spurious IRQ 7, just message is printed only once during kernel lifetime... I have about three spurious IRQ 7 per each 1000 interrupts delivered to CPU. It is on A7V (Via KT133).
Any idea _why_ these occur though? It seems some mainboards produce a plethora of these whilst others never produce these...
Nope. Probably when CPU is in local APIC mode, it acknowledges interrupts to chipset with different timming, and from time to time CPU still sees IRQ pending, so it asks for vector, but as chipset has no interrupt pending, it answers with IRQ7. I did no analysis to find whether IRQ7 happens directly when we send confirmation to 8259, or whether it happens due to some noise on IRQ line.
Quoted 2 lines
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
This (APIC errors) happened very often with my BP6 board too, but with recent kernels I don't get many of these messages.
As for spurious interrupts, I had these coming every five minutes on my Cyrix 6x86/SiS 5597 box. But this "settled" when I moved the box to another corner in the room, and also did some interior adjustments of cables and such (it is a server running in a very crammed slimline desktop box, with a HUB taped to the floppy mount =)
_____________________________________________________
| Martin Eriksson <[email protected]> | MSc CSE student, department of Computing Science | Umeå University, Sweden
Quoted 9 lines · Petr Vandrovec
Nope. Probably when CPU is in local APIC mode, it acknowledges interrupts to chipset with different timming, and from time to time CPU still sees IRQ pending, so it asks for vector, but as chipset has no interrupt pending, it answers with IRQ7. I did no analysis to find whether IRQ7 happens directly when we send confirmation to 8259, or whether it happens due to some noise on IRQ line.
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
My system is based on AMD's own 750 Irongate chipset, and it produces both the initial spurious IRQ7 message and plentiful "ERR" interrupts:
srwalter@hapablap:~$ uptime 11:31am up 42 days, 18:19, 1 user, load average: 1.04, 1.02, 1.00 srwalter@hapablap:~$ cat /proc/interrupts | grep ERR ERR: 67169
Signature · 6 lines
-Steven In a time of universal deceit, telling the truth is a revolutionary act. -- George Orwell He's alive. He's alive! Oh, that fellow at RadioShack said I was mad! Well, who's mad now? -- Montgomery C. Burns
From: Steven Walter <[email protected]>
Subject: Re: "APIC error on CPUx" - what does this mean?
Date: Mon, 7 Jan 2002 11:32:27 -0600
Quoted 8 lines · Petr Vandrovec
Quoted 7 lines
Nope. Probably when CPU is in local APIC mode, it acknowledges interrupts to chipset with different timming, and from time to time CPU still sees IRQ pending, so it asks for vector, but as chipset has no interrupt pending, it answers with IRQ7. I did no analysis to find whether IRQ7 happens directly when we send confirmation to 8259, or whether it happens due to some noise on IRQ line.
Quoted 5 lines
Quoted 2 lines
AFAIK it happens only on VIA based boards, and only if (AMD) CPU is using APIC.
My system is based on AMD's own 750 Irongate chipset, and it produces both the initial spurious IRQ7 message and plentiful "ERR" interrupts:
All my machines (from SiS 735, over Intel-BX to older Aladin-5 (super7) boxes) producing such "spurious IRQ7" with the actual 2.4.16 or 2.4.17 kernels ...
Quoted 17 lines
srwalter@hapablap:~$ uptime 11:31am up 42 days, 18:19, 1 user, load average: 1.04, 1.02, 1.00 srwalter@hapablap:~$ cat /proc/interrupts | grep ERR ERR: 67169Signature · 11 lines
-Steven In a time of universal deceit, telling the truth is a revolutionary act. -- George Orwell He's alive. He's alive! Oh, that fellow at RadioShack said I was mad! Well, who's mad now? -- Montgomery C. Burns - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/