03.05.2016 20:31, Andy Lutomirski пишет:
Using bit 4 divides the space of available bits strangely. Use bit
31 instead so that we have a better chance of keeping flag and mode
bits separate in the long run.
Cc: Stas Sergeev <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Aleksa Sarai <[email protected]>
Cc: Amanieu d'Antras <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Heinrich Schuchardt <[email protected]>
Cc: Jason Low <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Konstantin Khlebnikov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Paul Moore <[email protected]>
Cc: Pavel Emelyanov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Sasha Levin <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Andy Lutomirski <[email protected]>
---
include/uapi/linux/signal.h | 2 +-
tools/testing/selftests/sigaltstack/sas.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/signal.h b/include/uapi/linux/signal.h
index 738826048af2..cd0804b6bfa2 100644
--- a/include/uapi/linux/signal.h
+++ b/include/uapi/linux/signal.h
@@ -8,7 +8,7 @@
#define SS_DISABLE 2
/* bit-flags */
-#define SS_AUTODISARM (1 << 4) /* disable sas during sighandling */
+#define SS_AUTODISARM (1U << 31) /* disable sas during sighandling */
And what if we are out of 32 bits for storing both mode and flags? :)
Well, yes, very unlikely, but I did it that way exactly so that
we can eventually promote to 64bit variable.
Doesn't matter at all, of course. Let it be any way you like.
