From abf11fd235c4a7279b0cba4353da29751ddbe7ad Mon Sep 17 00:00:00 2001 From: Jordi Deu-Pons Date: Fri, 9 Oct 2026 12:48:45 +0200 Subject: [PATCH] build_library/oem/ami: Drop bare earlycon on arm64 Bare earlycon picks the UART address from the ACPI SPCR table, which on Graviton reports 0x80000000 instead of the real UART. When an NVMe BAR is mapped at that address (e.g. t4g with an additional EBS volume), the early 8250 console spins forever and boot hangs. The serial console is still set up by console=ttyS0, so only early boot output is lost. Signed-off-by: Jordi Deu-Pons --- build_library/oem/ami/grub.cfg | 2 +- changelog/bugfixes/2026-10-09-ec2-arm64-earlycon.md | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) create mode 100644 changelog/bugfixes/2026-10-09-ec2-arm64-earlycon.md diff --git a/build_library/oem/ami/grub.cfg b/build_library/oem/ami/grub.cfg index 7b18156766d..1c56306b54e 100644 --- a/build_library/oem/ami/grub.cfg +++ b/build_library/oem/ami/grub.cfg @@ -13,5 +13,5 @@ if [ "$grub_platform" = pc ]; then terminal_output serial_com0 fi if [ "$grub_cpu" = arm64 ]; then - set linux_console="console=tty1 console=ttyS0,115200n8 earlycon" + set linux_console="console=tty1 console=ttyS0,115200n8" fi diff --git a/changelog/bugfixes/2026-10-09-ec2-arm64-earlycon.md b/changelog/bugfixes/2026-10-09-ec2-arm64-earlycon.md new file mode 100644 index 00000000000..af48f919102 --- /dev/null +++ b/changelog/bugfixes/2026-10-09-ec2-arm64-earlycon.md @@ -0,0 +1 @@ +- AWS arm64: Removed bare `earlycon` from the kernel command line. It took the UART address from the ACPI SPCR table, which is wrong on Graviton, and could hang boot when an NVMe device was mapped at that address, e.g. on t4g instances with an additional EBS volume. ([Flatcar#2446](https://github.com/flatcar/Flatcar/issues/2446))