The process of applying hypervisor relocations involves patching
addresses in the hypervisor object. In the existing KVM nVHE relocation
procedure, the relocations are applied early enough for write-permission
not to be a problem when touching e.g. the rodata section. But applying
relocations on hypervisor modules embedded in a kernel module proves
more challenging, as the kernel module loader will actively map text and
rodata sections read-only. In order to allow patching in those sections,
let's introduce a new helper function using the text fixmap to
temporarily map the relevant pages writable.
Bug: 244543039
Bug: 244373730
Change-Id: I9dcdade1927e5bc121db87bc950fb70a374c44cd
Signed-off-by: Quentin Perret <qperret@google.com>
Currently, <asm/insn.h> includes <asm/patching.h>. We intend that
<asm/insn.h> will be usable from userspace, so it doesn't make sense to
include headers for kernel-only features such as the patching routines,
and we'd intended to restrict <asm/insn.h> to instruction encoding
details.
Let's decouple the patching code from <asm/insn.h>, and explicitly
include <asm/patching.h> where it is needed. Since <asm/patching.h>
isn't included from assembly, we can drop the __ASSEMBLY__ guards.
At the same time, sort the kprobes includes so that it's easier to see
what is and isn't incldued.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210609102301.17332-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
