| Message ID | 912b349e2bcaa88939904815ca0af945740c6bd4.1618478922.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: ptdump: Fix build failure | expand |
On 15/04/2021 10:31, Christophe Leroy wrote: > CC mm/ptdump.o > In file included from <command-line>: > mm/ptdump.c: In function 'ptdump_pte_entry': > ././include/linux/compiler_types.h:320:38: error: call to '__compiletime_assert_207' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE(). > 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) > | ^ > ././include/linux/compiler_types.h:301:4: note: in definition of macro '__compiletime_assert' > 301 | prefix ## suffix(); \ > | ^~~~~~ > ././include/linux/compiler_types.h:320:2: note: in expansion of macro '_compiletime_assert' > 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) > | ^~~~~~~~~~~~~~~~~~~ > ./include/asm-generic/rwonce.h:36:2: note: in expansion of macro 'compiletime_assert' > 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ > | ^~~~~~~~~~~~~~~~~~ > ./include/asm-generic/rwonce.h:49:2: note: in expansion of macro 'compiletime_assert_rwonce_type' > 49 | compiletime_assert_rwonce_type(x); \ > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > mm/ptdump.c:114:14: note: in expansion of macro 'READ_ONCE' > 114 | pte_t val = READ_ONCE(*pte); > | ^~~~~~~~~ > make[2]: *** [mm/ptdump.o] Error 1 > > READ_ONCE() cannot be used for reading PTEs. Use ptep_get() > instead. See commit 481e980a7c19 ("mm: Allow arches to provide ptep_get()") > and commit c0e1c8c22beb ("powerpc/8xx: Provide ptep_get() with 16k pages") > for details. It was cargo-culted from the arm64/x86 implementations (where this happens to be safe). > Fixes: 30d621f6723b ("mm: add generic ptdump") > Cc: Steven Price <steven.price@arm.com> > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Steven Price <steven.price@arm.com> Thanks, Steve > --- > mm/ptdump.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/ptdump.c b/mm/ptdump.c > index 4354c1422d57..da751448d0e4 100644 > --- a/mm/ptdump.c > +++ b/mm/ptdump.c > @@ -111,7 +111,7 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, > unsigned long next, struct mm_walk *walk) > { > struct ptdump_state *st = walk->private; > - pte_t val = READ_ONCE(*pte); > + pte_t val = ptep_get(pte); > > if (st->effective_prot) > st->effective_prot(st, 4, pte_val(val)); >
diff --git a/mm/ptdump.c b/mm/ptdump.c index 4354c1422d57..da751448d0e4 100644 --- a/mm/ptdump.c +++ b/mm/ptdump.c @@ -111,7 +111,7 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - pte_t val = READ_ONCE(*pte); + pte_t val = ptep_get(pte); if (st->effective_prot) st->effective_prot(st, 4, pte_val(val));
CC mm/ptdump.o In file included from <command-line>: mm/ptdump.c: In function 'ptdump_pte_entry': ././include/linux/compiler_types.h:320:38: error: call to '__compiletime_assert_207' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE(). 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^ ././include/linux/compiler_types.h:301:4: note: in definition of macro '__compiletime_assert' 301 | prefix ## suffix(); \ | ^~~~~~ ././include/linux/compiler_types.h:320:2: note: in expansion of macro '_compiletime_assert' 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ ./include/asm-generic/rwonce.h:36:2: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ ./include/asm-generic/rwonce.h:49:2: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/ptdump.c:114:14: note: in expansion of macro 'READ_ONCE' 114 | pte_t val = READ_ONCE(*pte); | ^~~~~~~~~ make[2]: *** [mm/ptdump.o] Error 1 READ_ONCE() cannot be used for reading PTEs. Use ptep_get() instead. See commit 481e980a7c19 ("mm: Allow arches to provide ptep_get()") and commit c0e1c8c22beb ("powerpc/8xx: Provide ptep_get() with 16k pages") for details. Fixes: 30d621f6723b ("mm: add generic ptdump") Cc: Steven Price <steven.price@arm.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- mm/ptdump.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)