Firmware bug error message on Arch on Apple
On Arch Linux on a MacBook Air 5.1 i get the error message
DMAR-IR: [Firmware Bug]: ioapic 2 has no mapping iommu,
interrupt remapping will be disabled
when booting. I can't notice any problem, but what is this?
Does it need to be fixed and if so how?
arch-linux macintosh firmware
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
add a comment |
On Arch Linux on a MacBook Air 5.1 i get the error message
DMAR-IR: [Firmware Bug]: ioapic 2 has no mapping iommu,
interrupt remapping will be disabled
when booting. I can't notice any problem, but what is this?
Does it need to be fixed and if so how?
arch-linux macintosh firmware
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
This seems to be agrubissue. Which version ofgrubdo you have?
– C.W.
Oct 18 '16 at 9:35
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51
add a comment |
On Arch Linux on a MacBook Air 5.1 i get the error message
DMAR-IR: [Firmware Bug]: ioapic 2 has no mapping iommu,
interrupt remapping will be disabled
when booting. I can't notice any problem, but what is this?
Does it need to be fixed and if so how?
arch-linux macintosh firmware
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
On Arch Linux on a MacBook Air 5.1 i get the error message
DMAR-IR: [Firmware Bug]: ioapic 2 has no mapping iommu,
interrupt remapping will be disabled
when booting. I can't notice any problem, but what is this?
Does it need to be fixed and if so how?
arch-linux macintosh firmware
arch-linux macintosh firmware
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
asked Oct 18 '16 at 8:48
ToothrotToothrot
843621
843621
This seems to be agrubissue. Which version ofgrubdo you have?
– C.W.
Oct 18 '16 at 9:35
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51
add a comment |
This seems to be agrubissue. Which version ofgrubdo you have?
– C.W.
Oct 18 '16 at 9:35
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51
This seems to be a
grub issue. Which version of grub do you have?– C.W.
Oct 18 '16 at 9:35
This seems to be a
grub issue. Which version of grub do you have?– C.W.
Oct 18 '16 at 9:35
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51
add a comment |
2 Answers
2
active
oldest
votes
In general: This feature allows the kernel to replace the remapping tables created by your BIOS.
If it's a system firmware bug, updates to Arch aren't going to fix it. You'd need to update your system firmware (BIOS/UEFI) by flashing. I personally don't recommend that. You should only do this if you really know how to flash your hardware.
The "soft" way is to disable the interrupt remapping in the kernel boot parameters. intremap=off disables the kernel interrupt remapping, which might point to your buggy bios or hardware.
First take a look at your config with cat /proc/cmdline. Copy it to see changes later on. Now back up your /etc/default/grub by copying it to a direction you want. To make the change persistent after a reboot edit /etc/default/grub and append your kernel options to the GRUB_CMDLINE_LINUX_DEFAULT line. In your case it is intremap=off (put it into the " "). You can delete the quiet if it is in there. Save it and exit.
Now re-generate the grub.cfg file (it is generated with the parameters written in /etc/default/grub) with:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot your system and the error should be gone. Take a look at your config with cat /proc/cmdline, your changes should be visable.
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
add a comment |
This is not an error message. Basically, Linux assumes that when there is an IO-APIC and an IOMMU, interrupt remapping must be supported. However, on this hardware it is not supported - the IO-APIC has ID 2 but the IOMMU only matches ID 0. Linux notices this situation, correctly disables interrupt remapping, and prints this notice to dmesg.
answered Apr 27 '17 at 21:46
jbgjbg
1032
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
In general: This feature allows the kernel to replace the remapping tables created by your BIOS.
If it's a system firmware bug, updates to Arch aren't going to fix it. You'd need to update your system firmware (BIOS/UEFI) by flashing. I personally don't recommend that. You should only do this if you really know how to flash your hardware.
The "soft" way is to disable the interrupt remapping in the kernel boot parameters. intremap=off disables the kernel interrupt remapping, which might point to your buggy bios or hardware.
First take a look at your config with cat /proc/cmdline. Copy it to see changes later on. Now back up your /etc/default/grub by copying it to a direction you want. To make the change persistent after a reboot edit /etc/default/grub and append your kernel options to the GRUB_CMDLINE_LINUX_DEFAULT line. In your case it is intremap=off (put it into the " "). You can delete the quiet if it is in there. Save it and exit.
Now re-generate the grub.cfg file (it is generated with the parameters written in /etc/default/grub) with:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot your system and the error should be gone. Take a look at your config with cat /proc/cmdline, your changes should be visable.
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
add a comment |
In general: This feature allows the kernel to replace the remapping tables created by your BIOS.
If it's a system firmware bug, updates to Arch aren't going to fix it. You'd need to update your system firmware (BIOS/UEFI) by flashing. I personally don't recommend that. You should only do this if you really know how to flash your hardware.
The "soft" way is to disable the interrupt remapping in the kernel boot parameters. intremap=off disables the kernel interrupt remapping, which might point to your buggy bios or hardware.
First take a look at your config with cat /proc/cmdline. Copy it to see changes later on. Now back up your /etc/default/grub by copying it to a direction you want. To make the change persistent after a reboot edit /etc/default/grub and append your kernel options to the GRUB_CMDLINE_LINUX_DEFAULT line. In your case it is intremap=off (put it into the " "). You can delete the quiet if it is in there. Save it and exit.
Now re-generate the grub.cfg file (it is generated with the parameters written in /etc/default/grub) with:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot your system and the error should be gone. Take a look at your config with cat /proc/cmdline, your changes should be visable.
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
add a comment |
In general: This feature allows the kernel to replace the remapping tables created by your BIOS.
If it's a system firmware bug, updates to Arch aren't going to fix it. You'd need to update your system firmware (BIOS/UEFI) by flashing. I personally don't recommend that. You should only do this if you really know how to flash your hardware.
The "soft" way is to disable the interrupt remapping in the kernel boot parameters. intremap=off disables the kernel interrupt remapping, which might point to your buggy bios or hardware.
First take a look at your config with cat /proc/cmdline. Copy it to see changes later on. Now back up your /etc/default/grub by copying it to a direction you want. To make the change persistent after a reboot edit /etc/default/grub and append your kernel options to the GRUB_CMDLINE_LINUX_DEFAULT line. In your case it is intremap=off (put it into the " "). You can delete the quiet if it is in there. Save it and exit.
Now re-generate the grub.cfg file (it is generated with the parameters written in /etc/default/grub) with:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot your system and the error should be gone. Take a look at your config with cat /proc/cmdline, your changes should be visable.
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
In general: This feature allows the kernel to replace the remapping tables created by your BIOS.
If it's a system firmware bug, updates to Arch aren't going to fix it. You'd need to update your system firmware (BIOS/UEFI) by flashing. I personally don't recommend that. You should only do this if you really know how to flash your hardware.
The "soft" way is to disable the interrupt remapping in the kernel boot parameters. intremap=off disables the kernel interrupt remapping, which might point to your buggy bios or hardware.
First take a look at your config with cat /proc/cmdline. Copy it to see changes later on. Now back up your /etc/default/grub by copying it to a direction you want. To make the change persistent after a reboot edit /etc/default/grub and append your kernel options to the GRUB_CMDLINE_LINUX_DEFAULT line. In your case it is intremap=off (put it into the " "). You can delete the quiet if it is in there. Save it and exit.
Now re-generate the grub.cfg file (it is generated with the parameters written in /etc/default/grub) with:
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot your system and the error should be gone. Take a look at your config with cat /proc/cmdline, your changes should be visable.
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
edited 8 mins ago
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
answered Oct 18 '16 at 17:08
C.W.C.W.
32719
32719
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
add a comment |
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
It seems that the interrupt is disabled anyway. Is there a reason to do this beyond getting rid of the error message?
– Toothrot
Oct 18 '16 at 20:06
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
To edit grub is a temporary workaround. The error is caused by a malfunctional firmware which flags to the operating system that it supports interrupt remapping despite the fact that is unable to handle it. So you have to update your motherboards chip-firmware to really get rid of it. BUT you don't need to, especially when your system is stable now.
– C.W.
Oct 19 '16 at 5:57
add a comment |
This is not an error message. Basically, Linux assumes that when there is an IO-APIC and an IOMMU, interrupt remapping must be supported. However, on this hardware it is not supported - the IO-APIC has ID 2 but the IOMMU only matches ID 0. Linux notices this situation, correctly disables interrupt remapping, and prints this notice to dmesg.
answered Apr 27 '17 at 21:46
jbgjbg
1032
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
add a comment |
This is not an error message. Basically, Linux assumes that when there is an IO-APIC and an IOMMU, interrupt remapping must be supported. However, on this hardware it is not supported - the IO-APIC has ID 2 but the IOMMU only matches ID 0. Linux notices this situation, correctly disables interrupt remapping, and prints this notice to dmesg.
answered Apr 27 '17 at 21:46
jbgjbg
1032
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
add a comment |
This is not an error message. Basically, Linux assumes that when there is an IO-APIC and an IOMMU, interrupt remapping must be supported. However, on this hardware it is not supported - the IO-APIC has ID 2 but the IOMMU only matches ID 0. Linux notices this situation, correctly disables interrupt remapping, and prints this notice to dmesg.
answered Apr 27 '17 at 21:46
jbgjbg
1032
This is not an error message. Basically, Linux assumes that when there is an IO-APIC and an IOMMU, interrupt remapping must be supported. However, on this hardware it is not supported - the IO-APIC has ID 2 but the IOMMU only matches ID 0. Linux notices this situation, correctly disables interrupt remapping, and prints this notice to dmesg.
answered Apr 27 '17 at 21:46
jbgjbg
1032
answered Apr 27 '17 at 21:46
jbgjbg
1032
answered Apr 27 '17 at 21:46
jbgjbg
1032
answered Apr 27 '17 at 21:46
jbgjbg
1032
1032
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
add a comment |
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
All right. Doesn't that make `Firmware bug' a bit inappropriate?
– Toothrot
Apr 28 '17 at 13:28
add a comment |
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This seems to be a
grubissue. Which version ofgrubdo you have?– C.W.
Oct 18 '16 at 9:35
@C.W., the last line of my grub-install man file says 2.02~beta3.
– Toothrot
Oct 18 '16 at 10:07
ok, i will write an answer as soon as i am at home
– C.W.
Oct 18 '16 at 11:51