| Message ID | 20190806232917.881-1-cai@lca.pw (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] asm-generic: fix variable 'p4d' set but not used | expand |
On Wed, Aug 7, 2019 at 1:29 AM Qian Cai <cai@lca.pw> wrote: > > A compiler throws a warning on an arm64 system since the > commit 9849a5697d3d ("arch, mm: convert all architectures to use > 5level-fixup.h"), > > mm/kasan/init.c: In function 'kasan_free_p4d': > mm/kasan/init.c:344:9: warning: variable 'p4d' set but not used > [-Wunused-but-set-variable] > p4d_t *p4d; > ^~~ > > because p4d_none() in "5level-fixup.h" is compiled away while it is a > static inline function in "pgtable-nopud.h". However, if converted > p4d_none() to a static inline there, powerpc would be unhappy as it > reads those in assembler language in > "arch/powerpc/include/asm/book3s/64/pgtable.h", so it needs to skip > assembly include for the static inline C function. While at it, > converted a few similar functions to be consistent with the ones in > "pgtable-nopud.h". > > Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Arnd Bergmann <arnd@arndb.de>
On Tue, Aug 06, 2019 at 07:29:17PM -0400, Qian Cai wrote: > A compiler throws a warning on an arm64 system since the > commit 9849a5697d3d ("arch, mm: convert all architectures to use > 5level-fixup.h"), > > mm/kasan/init.c: In function 'kasan_free_p4d': > mm/kasan/init.c:344:9: warning: variable 'p4d' set but not used > [-Wunused-but-set-variable] > p4d_t *p4d; > ^~~ > > because p4d_none() in "5level-fixup.h" is compiled away while it is a > static inline function in "pgtable-nopud.h". However, if converted > p4d_none() to a static inline there, powerpc would be unhappy as it > reads those in assembler language in > "arch/powerpc/include/asm/book3s/64/pgtable.h", so it needs to skip > assembly include for the static inline C function. While at it, > converted a few similar functions to be consistent with the ones in > "pgtable-nopud.h". > > Signed-off-by: Qian Cai <cai@lca.pw> > Acked-by: Arnd Bergmann <arnd@arndb.de> All parisc builds fail with this patch applied. include/asm-generic/5level-fixup.h:14:18: error: unknown type name 'pgd_t'; did you mean 'pid_t'? Bisect results below. Guenter --- # bad: [329120423947e8b36fd2f8b5cf69944405d0aece] Merge tag 'auxdisplay-for-linus-v5.3-rc5' of git://github.com/ojeda/linux # good: [ee1c7bd33e66376067fd6306b730789ee2ae53e4] Merge tag 'tpmdd-next-20190813' of git://git.infradead.org/users/jjs/linux-tpmdd git bisect start 'HEAD' 'ee1c7bd33e66' # bad: [e83b009c5c366b678c7986fa6c1d38fed06c954c] Merge tag 'dma-mapping-5.3-4' of git://git.infradead.org/users/hch/dma-mapping git bisect bad e83b009c5c366b678c7986fa6c1d38fed06c954c # bad: [92717d429b38e4f9f934eed7e605cc42858f1839] Revert "Revert "mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask"" git bisect bad 92717d429b38e4f9f934eed7e605cc42858f1839 # good: [b997052bc3ac444a0bceab1093aff7ae71ed419e] mm/z3fold.c: fix z3fold_destroy_pool() race condition git bisect good b997052bc3ac444a0bceab1093aff7ae71ed419e # good: [951531691c4bcaa59f56a316e018bc2ff1ddf855] mm/usercopy: use memory range to be accessed for wraparound check git bisect good 951531691c4bcaa59f56a316e018bc2ff1ddf855 # good: [6a2aeab59e97101b4001bac84388fc49a992f87e] seq_file: fix problem when seeking mid-record git bisect good 6a2aeab59e97101b4001bac84388fc49a992f87e # bad: [0cfaee2af3a04c0be5f056cebe5f804dedc59a43] include/asm-generic/5level-fixup.h: fix variable 'p4d' set but not used git bisect bad 0cfaee2af3a04c0be5f056cebe5f804dedc59a43 # first bad commit: [0cfaee2af3a04c0be5f056cebe5f804dedc59a43] include/asm-generic/5level-fixup.h: fix variable 'p4d' set but not used
diff --git a/include/asm-generic/5level-fixup.h b/include/asm-generic/5level-fixup.h index bb6cb347018c..f6947da70d71 100644 --- a/include/asm-generic/5level-fixup.h +++ b/include/asm-generic/5level-fixup.h @@ -19,9 +19,24 @@ #define p4d_alloc(mm, pgd, address) (pgd) #define p4d_offset(pgd, start) (pgd) -#define p4d_none(p4d) 0 -#define p4d_bad(p4d) 0 -#define p4d_present(p4d) 1 + +#ifndef __ASSEMBLY__ +static inline int p4d_none(p4d_t p4d) +{ + return 0; +} + +static inline int p4d_bad(p4d_t p4d) +{ + return 0; +} + +static inline int p4d_present(p4d_t p4d) +{ + return 1; +} +#endif + #define p4d_ERROR(p4d) do { } while (0) #define p4d_clear(p4d) pgd_clear(p4d) #define p4d_val(p4d) pgd_val(p4d)
A compiler throws a warning on an arm64 system since the commit 9849a5697d3d ("arch, mm: convert all architectures to use 5level-fixup.h"), mm/kasan/init.c: In function 'kasan_free_p4d': mm/kasan/init.c:344:9: warning: variable 'p4d' set but not used [-Wunused-but-set-variable] p4d_t *p4d; ^~~ because p4d_none() in "5level-fixup.h" is compiled away while it is a static inline function in "pgtable-nopud.h". However, if converted p4d_none() to a static inline there, powerpc would be unhappy as it reads those in assembler language in "arch/powerpc/include/asm/book3s/64/pgtable.h", so it needs to skip assembly include for the static inline C function. While at it, converted a few similar functions to be consistent with the ones in "pgtable-nopud.h". Signed-off-by: Qian Cai <cai@lca.pw> --- v2: Convert them to static inline functions. include/asm-generic/5level-fixup.h | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-)