diff options
-rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index b92e040466c1..3f07c370f761 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -242,6 +242,12 @@ SECTIONS __x86_cpu_dev_end = .; } + /* + * start address and size of operations which during runtime + * can be patched with virtualization friendly instructions or + * baremetal native ones. Think page table operations. + * Details in paravirt_types.h + */ . = ALIGN(8); .parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) { __parainstructions = .; @@ -249,6 +255,11 @@ SECTIONS __parainstructions_end = .; } + /* + * struct alt_inst entries. From the header (alternative.h): + * "Alternative instructions for different CPU types or capabilities" + * Think locking instructions on spinlocks. + */ . = ALIGN(8); .altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) { __alt_instructions = .; @@ -256,10 +267,21 @@ SECTIONS __alt_instructions_end = .; } + /* + * And here are the replacement instructions. The linker sticks + * them as binary blobs. The .altinstructions has enough data to + * get the address and the length of them to patch the kernel safely. + */ .altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) { *(.altinstr_replacement) } + /* + * struct iommu_table_entry entries are injected in this section. + * It is an array of IOMMUs which during run time gets sorted depending + * on its dependency order. After rootfs_initcall is complete + * this section can be safely removed. + */ .iommu_table : AT(ADDR(.iommu_table) - LOAD_OFFSET) { __iommu_table = .; *(.iommu_table) |