On Fri, 2022-10-21 at 16:22 +1100, Benjamin Gray wrote: > Verifies that if the instruction patching did not return an error > then > the value stored at the given address to patch is now equal to the > instruction we patched it to. > > Signed-off-by: Benjamin Gray <bg...@linux.ibm.com> > --- > arch/powerpc/lib/code-patching.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/powerpc/lib/code-patching.c > b/arch/powerpc/lib/code-patching.c > index 34fc7ac34d91..9b9eba574d7e 100644 > --- a/arch/powerpc/lib/code-patching.c > +++ b/arch/powerpc/lib/code-patching.c > @@ -186,6 +186,8 @@ static int do_patch_instruction(u32 *addr, > ppc_inst_t instr) > err = __do_patch_instruction(addr, instr); > local_irq_restore(flags); > > + WARN_ON(!err && !ppc_inst_equal(instr, ppc_inst_read(addr))); > +
As a side note, I had a look at test-code-patching.c and it doesn't look like we don't have a test for ppc_inst_equal() with prefixed instructions. We should fix that. > return err; > } > #else /* !CONFIG_STRICT_KERNEL_RWX */
