The fixup_group_size() function assumes that all .fixup rela groups end
with a jmpq instruction. That assumption turns out to be false when you
take into account the ____kvm_handle_fault_on_reboot() macro which is
used by kvm.
This is a new, more reliable method. It turns out that each .fixup
group is referenced by the __ex_table section. The new algorithm goes
through the __ex_table relas to figure out the size of each .fixup
group.
Also the .fixup section is now processed before __ex_table, because it
needs to access the original __ex_table relas before the unused ones
have been stripped.
Fixes the following error:
ERROR: vmx.o: fixup_group_size: 1554: can't find jump instruction in .fixup section
For ftrace to be able to trace a patched function, it requires that the
__mcount_loc section contains a pointer to the function, and that the
first instruction of the function is "callq __fentry__".
Normally that work is done by the recordmcount script, but it ignores
functions that aren't in a few standard sections (.text and a few
others).
The kpatch_regenerate_* functions use a local list_head to construct the
new list. While the local list_head is copied to the sec->relas after
it is built, the neighboring nodes in the list are not updated, leading
to list corruption.
This commit uses list_replace() which updates the neighbor nodes properly.
Regression introduced by PR #1175d36dd1.
Fixes#185.
Signed-off-by: Seth Jennings <sjenning@redhat.com>
Weinan Liu
Josh Poimboeuf
Seth Jennings