Questions tagged [nmi]

7 questions
11
votes
5 answers

Unknown NMI reason 20 and 30 on a VM

I pulled up the console on a virtual machine I manage today and was greeted with some kernel messages: [5912557.130943] Uhhuh. NMI received for unknown reason 20 on CPU 0. [5912557.131115] Do you have a strange power saving mode…
derobert
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10
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1 answer

Should I disable NMI watchdog permanently or not?

Why we need to keep the nmi_watchdog enabled and what could happen if I disable it permanently ? As some applications recommends to disable NMI watchdog to work properly, what's the advantage of disabling it ? And what does the results of this…
Arnab
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6
votes
1 answer

What does ACPI NMI LINT mean? and Why it changes across kernel version?

I'd like to understand what the following lines mean [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0x01] dfl dfl lint[0x0]) [ 0.000000] ACPI: NMI not connected to LINT 1! [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0x02] dfl dfl lint[0x0]) [ 0.000000]…
mattia.b89
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1
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0 answers

What happend if preempt_enable() inside an nmi?

https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-8/-/blob/ccf40dfacd314ab0fea16cfc6f4eded1a08e2710/arch/x86/kernel/cpu/mce/core.c#L1331 preempt_enable() before nmi_exit(), is this a OK code? if ((m.cs & 3) == 3) { /* If…
Mark K
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1
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0 answers

Custom interrupt handler for the NMI hardware button

I'm trying to create a custom interrupt handler for the NMI hardware button which exists on my motherboard. To test this functionality I've created this simple module: #include #include #include…
kostr22
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1
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1 answer

Can't disable NMI watchdog on Debian Buster in vmware context - couldn't write to kernel, unknown error 524

Following instructions, I want to disable the NMI watchdog on boot. sudo sh -c "echo '0' > /proc/sys/kernel/nmi_watchdog" However: Couldn't write '0' to 'kernel/nmi_watchdog': Unknown error 524 How to proceed?
J. Doe
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How to have the kernel print a stacktrace when sending a Hardware NMI

I have Qemu VMs running FreeBSD, Windows and Linux, and I can send them a hardware NMI via the Qemu monitor. qm monitor 100 Entering Qemu Monitor for VM 100 - type 'help' for help qm> help nmi nmi -- inject an NMI When inkecting the NMI to a…
Manu
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