diff options
| author | Jessica Yu <jeyu@redhat.com> | 2016-08-17 20:58:29 -0400 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2016-08-18 23:41:55 +0200 |
| commit | d4c3e6e1b193497da3a2ce495fb1db0243e41e37 (patch) | |
| tree | 8d0307b2403b25fd7aa808a01e59d62d6f9fa202 /arch/x86/kernel/Makefile | |
| parent | 255e732c61dbb6a0bf9e0a3d6bc45f202853c880 (diff) | |
livepatch/x86: apply alternatives and paravirt patches after relocations
Implement arch_klp_init_object_loaded() for x86, which applies
alternatives/paravirt patches. This fixes the order in which relocations
and alternatives/paravirt patches are applied.
Previously, if a patch module had alternatives or paravirt patches,
these were applied first by the module loader before livepatch can apply
per-object relocations. The (buggy) sequence of events was:
(1) Load patch module
(2) Apply alternatives and paravirt patches to patch module
* Note that these are applied to the new functions in the patch module
(3) Apply per-object relocations to patch module when target module loads.
* This clobbers what was written in step 2
This lead to crashes and corruption in general, since livepatch would
overwrite or step on previously applied alternative/paravirt patches.
The correct sequence of events should be:
(1) Load patch module
(2) Apply per-object relocations to patch module
(3) Apply alternatives and paravirt patches to patch module
This is fixed by delaying paravirt/alternatives patching until after
relocations are applied. Any .altinstructions or .parainstructions
sections are prefixed with ".klp.arch.${objname}" and applied in
arch_klp_init_object_loaded().
Signed-off-by: Jessica Yu <jeyu@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'arch/x86/kernel/Makefile')
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 0503f5bfb18d..4f656fe156fd 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -83,6 +83,7 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-y += apic/ obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o +obj-$(CONFIG_LIVEPATCH) += livepatch.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o obj-$(CONFIG_X86_TSC) += trace_clock.o |