On Fri, 2024-03-15 at 06:39 +0000, Christophe Leroy wrote: > > > Le 15/03/2024 à 03:57, Benjamin Gray a écrit : > > As we are patching instructions, we can assume the length is a > > multiple > > of 4 and the destination address is aligned. > > > > Atomicity of patching a prefixed instruction is not a concern, as > > the > > original implementation doesn't provide it anyway. > > This patch looks unnecessary. > > copy_to_kernel_nofault() is what you want to use instead.
Yeah, I would drop this patch when using copy_to_kernel_nofault() > > > > > Signed-off-by: Benjamin Gray <bg...@linux.ibm.com> > > --- > > arch/powerpc/lib/code-patching.c | 8 ++++---- > > 1 file changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/arch/powerpc/lib/code-patching.c > > b/arch/powerpc/lib/code-patching.c > > index c6633759b509..ed450a32918c 100644 > > --- a/arch/powerpc/lib/code-patching.c > > +++ b/arch/powerpc/lib/code-patching.c > > @@ -394,10 +394,10 @@ static int patch_memset32(u32 *addr, u32 val, > > size_t count) > > return -EPERM; > > } > > > > -static int patch_memcpy(void *dst, void *src, size_t len) > > +static int patch_memcpy32(u32 *dst, u32 *src, size_t count) > > { > > - for (void *end = src + len; src < end; dst++, src++) > > - __put_kernel_nofault(dst, src, u8, failed); > > + for (u32 *end = src + count; src < end; dst++, src++) > > + __put_kernel_nofault(dst, src, u32, failed); > > > > return 0; > > > > @@ -424,7 +424,7 @@ static int __patch_instructions(u32 > > *patch_addr, u32 *code, size_t len, bool rep > > err = patch_memset32(patch_addr, val, len > > / 4); > > } > > } else { > > - err = patch_memcpy(patch_addr, code, len); > > + err = patch_memcpy32(patch_addr, code, len / 4); > > } > > > > smp_wmb(); /* smp write barrier */