On Fri, Apr 16, 2021 at 01:28:21PM +0530, Aneesh Kumar K.V wrote: > On 4/15/21 7:16 PM, Andy Shevchenko wrote: > > Parse to and export from UUID own type, before dereferencing. > > This also fixes wrong comment (Little Endian UUID is something else) > > and should fix Sparse warnings about assigning strict types to POD. > > > > Fixes: 43001c52b603 ("powerpc/papr_scm: Use ibm,unit-guid as the iset > > cookie") > > Fixes: 259a948c4ba1 ("powerpc/pseries/scm: Use a specific endian format for > > storing uuid from the device tree") > > Cc: Oliver O'Halloran <ooh...@gmail.com> > > Cc: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com> > > Signed-off-by: Andy Shevchenko <andriy.shevche...@linux.intel.com> > > --- > > Not tested > > arch/powerpc/platforms/pseries/papr_scm.c | 13 ++++++++----- > > 1 file changed, 8 insertions(+), 5 deletions(-) > > > > diff --git a/arch/powerpc/platforms/pseries/papr_scm.c > > b/arch/powerpc/platforms/pseries/papr_scm.c > > index ae6f5d80d5ce..4366e1902890 100644 > > --- a/arch/powerpc/platforms/pseries/papr_scm.c > > +++ b/arch/powerpc/platforms/pseries/papr_scm.c > > @@ -1085,8 +1085,9 @@ static int papr_scm_probe(struct platform_device > > *pdev) > > u32 drc_index, metadata_size; > > u64 blocks, block_size; > > struct papr_scm_priv *p; > > + u8 uuid_raw[UUID_SIZE]; > > const char *uuid_str; > > - u64 uuid[2]; > > + uuid_t uuid; > > int rc; > > /* check we have all the required DT properties */ > > @@ -1129,16 +1130,18 @@ static int papr_scm_probe(struct platform_device > > *pdev) > > p->hcall_flush_required = of_property_read_bool(dn, > > "ibm,hcall-flush-required"); > > /* We just need to ensure that set cookies are unique across */ > > - uuid_parse(uuid_str, (uuid_t *) uuid); > > + uuid_parse(uuid_str, &uuid); > > + > > /* > > * cookie1 and cookie2 are not really little endian > > - * we store a little endian representation of the > > + * we store a raw buffer representation of the > > * uuid str so that we can compare this with the label > > * area cookie irrespective of the endian config with which > > * the kernel is built. > > */ > > - p->nd_set.cookie1 = cpu_to_le64(uuid[0]); > > - p->nd_set.cookie2 = cpu_to_le64(uuid[1]); > > + export_uuid(uuid_raw, &uuid); > > + p->nd_set.cookie1 = get_unaligned_le64(&uuid_raw[0]); > > + p->nd_set.cookie2 = get_unaligned_le64(&uuid_raw[8]); > > ok that does the equivalent of cpu_to_le64 there. So we are good. But the > comment update is missing the details why we did that get_unaligned_le64. > Maybe raw buffer representation is the correct term? > Should we add an example in the comment. ie,
> /* > * Historically we stored the cookie in the below format. > for a uuid str 72511b67-0b3b-42fd-8d1d-5be3cae8bcaa > cookie1 was 0xfd423b0b671b5172 cookie2 was 0xaabce8cae35b1d8d > */ I'm fine with the comment. At least it will shed a light on the byte ordering we are expecting. > > /* might be zero */ > > p->metadata_size = metadata_size; -- With Best Regards, Andy Shevchenko