mirror of
https://git.proxmox.com/git/mirror_ubuntu-kernels.git
synced 2025-12-14 21:33:17 +00:00
The decompressor has a hard limit on the number of page tables it can
allocate. This limit is defined at compile-time and will cause boot
failure if it is reached.
The kernel is very strict and calculates the limit precisely for the
worst-case scenario based on the current configuration. However, it is
easy to forget to adjust the limit when a new use-case arises. The
worst-case scenario is rarely encountered during sanity checks.
In the case of enabling 5-level paging, a use-case was overlooked. The
limit needs to be increased by one to accommodate the additional level.
This oversight went unnoticed until Aaron attempted to run the kernel
via kexec with 5-level paging and unaccepted memory enabled.
Update wost-case calculations to include 5-level paging.
To address this issue, let's allocate some extra space for page tables.
128K should be sufficient for any use-case. The logic can be simplified
by using a single value for all kernel configurations.
[ Also add a warning, should this memory run low - by Dave Hansen. ]
Fixes:
|
||
|---|---|---|
| .. | ||
| compressed | ||
| tools | ||
| .gitignore | ||
| a20.c | ||
| apm.c | ||
| bioscall.S | ||
| bitops.h | ||
| boot.h | ||
| cmdline.c | ||
| copy.S | ||
| cpu.c | ||
| cpucheck.c | ||
| cpuflags.c | ||
| cpuflags.h | ||
| ctype.h | ||
| early_serial_console.c | ||
| edd.c | ||
| genimage.sh | ||
| header.S | ||
| install.sh | ||
| io.h | ||
| main.c | ||
| Makefile | ||
| memory.c | ||
| mkcpustr.c | ||
| msr.h | ||
| mtools.conf.in | ||
| pm.c | ||
| pmjump.S | ||
| printf.c | ||
| regs.c | ||
| setup.ld | ||
| string.c | ||
| string.h | ||
| tty.c | ||
| version.c | ||
| vesa.h | ||
| video-bios.c | ||
| video-mode.c | ||
| video-vesa.c | ||
| video-vga.c | ||
| video.c | ||
| video.h | ||