On Tue, Mar 26, 2019 at 3:26 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > On Mon, Mar 25, 2019 at 01:14:25PM -0500, helgaas@xxxxxxxxxx wrote: > > From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > > > "__u32" and similar types are intended for things exported to user-space, > > including structs used in ioctls; see include/uapi/asm-generic/int-l64.h. > > > > They are not needed for the CPER struct definitions, which not exported to > > user-space and not used in ioctls. Replace them with the typical "u32" and > > similar types. No functional change intended. > > > > The reason for changing this is to remove the question of "why do we use > > __u32 here instead of u32?" We should use __u32 when there's a reason for > > it; otherwise, we should prefer u32 for consistency. > > > > Reference: Documentation/process/coding-style.rst > > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > CC: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > CC: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > I cc'd you folks because you were part of this conversation: > > https://lore.kernel.org/lkml/1526350925-14922-3-git-send-email-yamada.masahiro@xxxxxxxxxxxxx/T/#u > > I *think* the conclusion there was that this sort of change makes > sense, but I want to make sure. If it does make sense, I'm surprised > at how much stuff in include/linux/ still uses __u32 when it doesn't > appear to need it. This patch looks good to me. I still fail to understand Greg's comment in the referred URL, though. "__u32" and similar types are intended for things exported to user-space. This is clearly documented. Documentation/process/coding-style.rst: (e) Types safe for use in userspace. In certain structures which are visible to userspace, we cannot require C99 types and cannot use the ``u32`` form above. Thus, we use __u32 and similar types in all structures which are shared with userspace. I'd be eager to see a document that suggests __u32 and similar types in ioctl structures. -- Best Regards Masahiro Yamada
