> -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Andrew Morton > Sent: Friday, August 21, 2020 8:55 AM > To: Naresh Kamboju <[email protected]> > Cc: Linux-Next Mailing List <[email protected]>; open list > <[email protected]>; linux-mm <[email protected]>; > [email protected]; Linuxarm <[email protected]>; Song Bao Hua > (Barry Song) <[email protected]>; John Hubbard > <[email protected]>; Jan Kara <[email protected]>; Jérôme Glisse > <[email protected]>; Matthew Wilcox (Oracle) <[email protected]>; Al > Viro <[email protected]>; Christoph Hellwig <[email protected]>; Dan > Williams <[email protected]>; Dave Chinner <[email protected]>; > Jason Gunthorpe <[email protected]>; Jonathan Corbet <[email protected]>; Michal > Hocko <[email protected]>; Mike Kravetz <[email protected]>; > Shuah Khan <[email protected]>; Vlastimil Babka <[email protected]> > Subject: Re: mm/gup.c:1922:7: error: implicit declaration of function > ‘is_valid_gup_flags’ > > On Thu, 20 Aug 2020 14:59:52 +0530 Naresh Kamboju > <[email protected]> wrote: > > > arm and riscv architecture build failed on linux next 20200820 tag. > > > > make -sk KBUILD_BUILD_USER=TuxBuild -C/linux -j16 ARCH=arm > > CROSS_COMPILE=arm-linux-gnueabihf- HOSTCC=gcc CC="sccache > > arm-linux-gnueabihf-gcc" O=build zImage > > > > 348# > > 349../mm/gup.c: In function ‘get_user_pages’: > > 350../mm/gup.c:1922:7: error: implicit declaration of function > > ‘is_valid_gup_flags’ [-Werror=implicit-function-declaration] > > 351 1922 | if (!is_valid_gup_flags(gup_flags)) > > 352 | ^~~~~~~~~~~~~~~~~~ > > 353cc1: some warnings being treated as errors > > > > Yes, thanks. > > From: Andrew Morton <[email protected]> > Subject: > mm-gup-dont-permit-users-to-call-get_user_pages-with-foll_longterm-fix > > fix CONFIG_MMU=n build > > Link: > https://lkml.kernel.org/r/CA+G9fYuNS3k0DVT62twfV746pfNhCSrk5sVMcOcQ1 > [email protected] > Reported-by: Naresh Kamboju <[email protected]> > Cc: Barry Song <[email protected]> > Cc: Stephen Rothwell <[email protected]> > Signed-off-by: Andrew Morton <[email protected]>
Andrew, Thanks for taking care of this build issue. Acked-by: Barry Song <[email protected]> > --- > > mm/gup.c | 38 +++++++++++++++++++------------------- > 1 file changed, 19 insertions(+), 19 deletions(-) > > --- > a/mm/gup.c~mm-gup-dont-permit-users-to-call-get_user_pages-with-foll_long > term-fix > +++ a/mm/gup.c > @@ -1759,6 +1759,25 @@ static __always_inline long __gup_longte } > #endif /* CONFIG_FS_DAX || CONFIG_CMA */ > > +static bool is_valid_gup_flags(unsigned int gup_flags) { > + /* > + * FOLL_PIN must only be set internally by the pin_user_pages*() APIs, > + * never directly by the caller, so enforce that with an assertion: > + */ > + if (WARN_ON_ONCE(gup_flags & FOLL_PIN)) > + return false; > + /* > + * FOLL_PIN is a prerequisite to FOLL_LONGTERM. Another way of saying > + * that is, FOLL_LONGTERM is a specific case, more restrictive case of > + * FOLL_PIN. > + */ > + if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM)) > + return false; > + > + return true; > +} > + > #ifdef CONFIG_MMU > static long __get_user_pages_remote(struct mm_struct *mm, > unsigned long start, unsigned long > nr_pages, @@ > -1789,25 +1808,6 @@ static long __get_user_pages_remote(stru > gup_flags | FOLL_TOUCH | FOLL_REMOTE); } > > -static bool is_valid_gup_flags(unsigned int gup_flags) -{ > - /* > - * FOLL_PIN must only be set internally by the pin_user_pages*() APIs, > - * never directly by the caller, so enforce that with an assertion: > - */ > - if (WARN_ON_ONCE(gup_flags & FOLL_PIN)) > - return false; > - /* > - * FOLL_PIN is a prerequisite to FOLL_LONGTERM. Another way of saying > - * that is, FOLL_LONGTERM is a specific case, more restrictive case of > - * FOLL_PIN. > - */ > - if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM)) > - return false; > - > - return true; > -} > - > /** > * get_user_pages_remote() - pin user pages in memory > * @mm: mm_struct of target mm > _ > Best Regards Barry
