Re: [tip:core/signals] signals/sigaltstack: Prepare to add new SS_xxx flags

From: Borislav Petkov
Date: Tue May 03 2016 - 05:59:29 EST


On Tue, May 03, 2016 at 12:50:06AM -0700, tip-bot for Stas Sergeev wrote:
> Commit-ID: 407bc16ad1769f5cb8ad9555611cb198187ef4cd
> Gitweb: http://git.kernel.org/tip/407bc16ad1769f5cb8ad9555611cb198187ef4cd
> Author: Stas Sergeev <stsp@xxxxxxx>
> AuthorDate: Thu, 14 Apr 2016 23:20:03 +0300
> Committer: Ingo Molnar <mingo@xxxxxxxxxx>
> CommitDate: Tue, 3 May 2016 08:37:59 +0200
>
> signals/sigaltstack: Prepare to add new SS_xxx flags
>
> This patch adds SS_FLAG_BITS - the mask that splits sigaltstack
> mode values and bit-flags. Since there is no bit-flags yet, the
> mask is defined to 0. The flags are added by subsequent patches.
> With every new flag, the mask should have the appropriate bit cleared.
>
> This makes sure if some flag is tried on a kernel that doesn't
> support it, the -EINVAL error will be returned, because such a
> flag will be treated as an invalid mode rather than the bit-flag.
>
> That way the existence of the particular features can be probed
> at run-time.
>
> This change was suggested by Andy Lutomirski:
>
> https://lkml.org/lkml/2016/3/6/158

Please use the message ID in the future

Message-ID: <CALCETrW=M1=n6R6dwOj-ks_=+14vf4rz0S3SFty-_GuwFFZU5A@xxxxxxxxxxxxxx>

to refer to public mails because random web services caching lkml tend
to become unreliable or even disappear at some point.

I.e., see Link: format below for an example.

> Signed-off-by: Stas Sergeev <stsp@xxxxxxx>
> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> Cc: Amanieu d'Antras <amanieu@xxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Cc: Brian Gerst <brgerst@xxxxxxxxx>
> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
> Cc: H. Peter Anvin <hpa@xxxxxxxxx>
> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxx>
> Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
> Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Richard Weinberger <richard@xxxxxx>
> Cc: Sasha Levin <sasha.levin@xxxxxxxxxx>
> Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
> Cc: linux-api@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Link: http://lkml.kernel.org/r/1460665206-13646-3-git-send-email-stsp@xxxxxxx
> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
> ---
> include/uapi/linux/signal.h | 3 +++
> kernel/signal.c | 16 ++++++----------
> 2 files changed, 9 insertions(+), 10 deletions(-)

Thanks.

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.