The text_poke API is used to implement functions like memcpy() and
memset() for instruction memory (RO+X). The implementation is similar to
the x86 version.
This will be used by the BPF JIT to write and modify BPF programs. There
could be more users of this in the future.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20240228141824.119877-2-puranjay12@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In subsequent patches we'll need to atomically write to a
naturally-aligned 64-bit literal embedded within the kernel text.
Add a helper for this. For consistency with other text patching code we
use copy_to_kernel_nofault(), which is atomic for naturally-aligned
accesses up to 64-bits.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230123134603.1064407-7-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.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>
Files insn.[c|h] containt some functions used for instruction patching.
In order to reuse the instruction encoder/decoder, move the patching
utilities to their own file.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Link: https://lore.kernel.org/r/20210303170536.1838032-2-jthierry@redhat.com
[will: Include patching.h in insn.h to fix header mess; add __ASSEMBLY__ guards]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Puranjay Mohan