On Tue, Jan 11, 2022 at 11:33 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Tue, Jan 11, 2022 at 9:35 AM Christoph Hellwig <hch@xxxxxx> wrote: > > > > The fcntl F_GETLK64/F_SETLK64/F_SETLKW64 are only implemented for the > > 32-bit syscall APIs, but we also need them for compat handling on 64-bit > > builds. Redefining them is error prone (as shown by the example that > > parisc gets it wrong currently), so we should use the same defines for > > both case. In theory we could try to hide them from userspace, but > > given that only MIPS actually gets that right, while the asm-generic > > version used by most architectures relies on a Kconfig symbol that can't > > be relied on to be set properly by userspace is a clear indicator to not > > bother. > > > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > > --- > > > diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h > > index 98f4ff165b776..43d7c44031be0 100644 > > --- a/include/uapi/asm-generic/fcntl.h > > +++ b/include/uapi/asm-generic/fcntl.h > > @@ -116,13 +116,11 @@ > > #define F_GETSIG 11 /* for sockets. */ > > #endif > > > > -#ifndef CONFIG_64BIT > > #ifndef F_GETLK64 > > #define F_GETLK64 12 /* using 'struct flock64' */ > > #define F_SETLK64 13 > > #define F_SETLKW64 14 > > #endif > > -#endif > > > > #ifndef F_SETOWN_EX > > #define F_SETOWN_EX 15 > > This is a very subtle change to the exported UAPI header contents: > On 64-bit architectures, the three unusable numbers are now always > shown, rather than depending on a user-controlled symbol. > > This is probably what we want here for compatibility reasons, but I think > it should be explained in the changelog text, and I'd like Jeff or Bruce > to comment on it as well: the alternative here would be to make the > uapi definition depend on __BITS_PER_LONG==32, which is __BITS_PER_LONG==32 || __KERNEL__ just for kernel use in compat. > technically the right thing to do but more a of a change. > > Arnd -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/
