On Thu, 20 Aug 2020 14:59:52 +0530 Naresh Kamboju <naresh.kamb...@linaro.org> 
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 <a...@linux-foundation.org>
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+g9fyuns3k0dvt62twfv746pfnhcsrk5svmcocq1pggnes...@mail.gmail.com
Reported-by: Naresh Kamboju <naresh.kamb...@linaro.org>
Cc: Barry Song <song.bao....@hisilicon.com>
Cc: Stephen Rothwell <s...@canb.auug.org.au>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
---

 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_longterm-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
_

Reply via email to