Le 15/12/2020 à 02:42, Michael Ellerman a écrit :
Christophe Leroy <christophe.le...@csgroup.eu> writes:
Le 14/12/2020 à 13:30, Michael Ellerman a écrit :
setup_kup() is used by both 64-bit and 32-bit code. However on 64-bit
it must not be __init, because it's used for CPU hotplug, whereas on
32-bit it should be __init because it calls setup_kuap/kuep() which
are __init.
We worked around that problem in the past by marking it __ref, see
commit 67d53f30e23e ("powerpc/mm: fix section mismatch for
setup_kup()").
Marking it __ref basically just omits it from section mismatch
checking, which can lead to bugs, and in fact it did, see commit
44b4c4450f8d ("powerpc/64s: Mark the kuap/kuep functions non __init")
We can avoid all these problems by just making it static inline.
Because all it does is call other functions, making it inline actually
shrinks the 32-bit vmlinux by ~76 bytes.
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
---
arch/powerpc/include/asm/kup.h | 8 ++++++--
arch/powerpc/mm/init-common.c | 6 ------
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h
index 5a9820c54da9..46b12c6dc728 100644
--- a/arch/powerpc/include/asm/kup.h
+++ b/arch/powerpc/include/asm/kup.h
@@ -49,8 +49,6 @@ extern bool disable_kuap;
#include <linux/pgtable.h>
-void setup_kup(void);
-
#ifdef CONFIG_PPC_KUEP
void setup_kuep(bool disabled);
#else
@@ -85,6 +83,12 @@ static inline void restore_user_access(unsigned long flags)
{ }
#endif /* CONFIG_PPC_BOOK3S_64 */
#endif /* CONFIG_PPC_KUAP */
+static inline void setup_kup(void)
Should it be __always_inline ?
Yes I guess so, will fix. Thanks for reviewing.
While we are talking about __always_inline, do you plan to take the following
patch this cycle ?
https://patchwork.ozlabs.org/project/linuxppc-dev/patch/a1d31f84ddb0926813b17fcd5cc7f3fa7b4deac2.1602759123.git.christophe.le...@csgroup.eu/
Christophe
