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After some years of trouble free UEFI use on a PC with a Kaveri APU, I've |
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suddenly come across a problem of incorrectly mounted efivarfs. I realised |
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something was amiss when I tried to set up a new kernel I had just copied into |
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/boot/EFI/BOOT/ |
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|
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# tree /boot |
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/boot |
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├── 42GHz2400MHz.CMO |
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└── EFI |
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└── BOOT |
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├── A88XM-PLUS-ASUS-3004.CAP |
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├── System.map-4.12.5-gentoo |
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├── System.map-4.9.34-gentoo |
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├── bootx64-4.12.5-gentoo.efi |
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├── bootx64-4.9.34-gentoo.efi <==This one |
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├── config-4.12.5-gentoo |
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└── config-4.9.34-gentoo |
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|
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2 directories, 8 files |
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|
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The error is generated whenever I try to create a new boot entry: |
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|
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# efibootmgr --create --disk /dev/sda --part 1 --label "gentoo-4.12.5-15_Aug" |
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--loader "\EFI\BOOT\bootx64-4.12.5-gentoo.efi" |
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Could not prepare Boot variable: Read-only file system |
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|
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Hmm ... looking more closely it seems /sys/firmware/efi/efivars was mounted as |
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'ro': |
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|
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# mount | grep efi |
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efivarfs on /sys/firmware/efi/efivars type efivarfs (ro,relatime) |
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|
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|
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I can't recall if I did this myself in a moment of security induced |
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inspiration. I doubt I did. So how did this happen? What is responsible for |
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mounting this fs? |
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|
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Should I remount it as 'rw' so I can set up the new kernel in the EFI stub, or |
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does this problem need further investigation? |
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|
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-- |
| 42 |
Regards, |
| 43 |
Mick |
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