From: Petr Mladek <pmladek@suse.com>
To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Dmitry Vyukov <dvyukov@google.com>,
syzkaller <syzkaller@googlegroups.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Andrew Morton <akpm@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Ondrej Mosnacek <omosnace@redhat.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>
Subject: Re: twist: allow disabling reboot request
Date: Wed, 3 Jun 2020 14:44:05 +0200 [thread overview]
Message-ID: <20200603124405.GA22497@linux-b0ei> (raw)
In-Reply-To: <51eaa6cd-33ce-f9d8-942c-c797c0ec6733@i-love.sakura.ne.jp>
On Wed 2020-06-03 20:03:28, Tetsuo Handa wrote:
> On 2020/05/29 22:26, Tetsuo Handa wrote:
> > By the way, I do worry that people forget to perform these steps when they do
> > their tests without asking syzbot...
>
> Here is a draft of boot-time switching. Since kconfig can handle string variable up to
> 2048 characters, we could hold the content of the "your-config" file inside .config file
> in order to avoid relying on external file in "syzkaller tree". But since only one kconfig
> option is used, basically the way to temporarily include/exclude specific options (under
> automated testing by syzbot) seems to remain directly patching apply_twist_flags(), for
> https://github.com/google/syzkaller/blob/master/dashboard/config/util.sh will automatically
> overwrite CONFIG_DEFAULT_TWIST_FLAGS settings. If each twist flag were using independent
> kconfig option, the way to temporarily include/exclude specific options will become directly
> patching Kconfig file.
>
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 82d91547d122..78fdbb4f17b1 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -1038,4 +1038,12 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
> /* OTHER_WRITABLE? Generally considered a bad idea. */ \
> BUILD_BUG_ON_ZERO((perms) & 2) + \
> (perms))
> +
> +/* Flags for twisting kernel behavior. */
> +struct twist_flags {
> + bool disable_kbd_k_spec_handler;
> + bool disable_reboot_request;
> +};
> +extern struct twist_flags twist_flags;
Why all these options have to be in a single structure?
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 498d344ea53a..41cfabc74ad7 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2338,4 +2338,9 @@ config HYPERV_TESTING
>
> endmenu # "Kernel Testing and Coverage"
>
> +menuconfig DEFAULT_TWIST_FLAGS
> + string "Default twist options (DANGEROUS)"
> + help
> + Don't specify anything unless you know what you are doing.
> +
> endmenu # Kernel hacking
Why such a crazy build configure option?
I think that the only way to get this upstream is to:
+ Add separate boot options that might theoretically be used also
by other people.
+ Use boot parameters and not build configuration.
+ Avoid the meaningless word "twist" !!!
Best Regards,
Petr
next prev parent reply other threads:[~2020-06-03 12:44 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-24 14:50 [PATCH] twist: allow converting pr_devel()/pr_debug() into printk(KERN_DEBUG) Tetsuo Handa
2020-05-24 17:38 ` Joe Perches
2020-05-24 19:18 ` Ondrej Mosnacek
2020-05-25 5:03 ` Tetsuo Handa
2020-05-25 6:07 ` Joe Perches
2020-05-25 7:38 ` Dmitry Vyukov
2020-05-25 8:42 ` Petr Mladek
2020-05-25 9:11 ` Sergey Senozhatsky
2020-05-25 10:43 ` Tetsuo Handa
2020-05-27 8:37 ` Petr Mladek
2020-05-27 10:13 ` Tetsuo Handa
2020-05-27 15:55 ` Petr Mladek
2020-05-27 23:33 ` Tetsuo Handa
2020-05-28 6:56 ` [PATCH v2] twist: allow converting pr_devel()/pr_debug() into snprintf() Tetsuo Handa
2020-05-28 11:06 ` Petr Mladek
2020-05-28 15:16 ` Tetsuo Handa
2020-05-28 19:10 ` Andrew Morton
2020-05-28 19:50 ` Linus Torvalds
2020-05-28 20:01 ` Linus Torvalds
2020-05-29 0:07 ` Tetsuo Handa
2020-05-29 0:28 ` Linus Torvalds
2020-05-29 2:13 ` Tetsuo Handa
2020-05-29 2:24 ` Linus Torvalds
2020-05-29 4:47 ` Tetsuo Handa
2020-05-29 13:26 ` Tetsuo Handa
2020-06-03 11:03 ` twist: allow disabling reboot request Tetsuo Handa
2020-06-03 12:44 ` Petr Mladek [this message]
2020-06-03 13:35 ` Tetsuo Handa
2020-06-04 10:21 ` Petr Mladek
2020-06-08 7:48 ` [PATCH v2] twist: allow converting pr_devel()/pr_debug() into snprintf() Dmitry Vyukov
2020-06-08 10:30 ` Tetsuo Handa
2020-06-08 11:31 ` Andrey Konovalov
2020-05-29 8:17 ` Petr Mladek
2020-06-08 16:39 ` Geert Uytterhoeven
2020-05-28 10:59 ` [PATCH] twist: allow converting pr_devel()/pr_debug() into printk(KERN_DEBUG) Petr Mladek
2020-05-28 11:33 ` Tetsuo Handa
2020-05-28 12:14 ` Petr Mladek
2020-05-28 14:13 ` Tetsuo Handa
2020-05-28 17:08 ` Joe Perches
2020-05-29 2:04 ` Sergey Senozhatsky
2020-05-29 5:06 ` Tetsuo Handa
2020-05-27 9:59 ` kbuild test robot
2020-05-27 13:41 ` Tetsuo Handa
2020-05-27 12:37 ` kbuild test robot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200603124405.GA22497@linux-b0ei \
--to=pmladek@suse.com \
--cc=akpm@linux-foundation.org \
--cc=dvyukov@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=omosnace@redhat.com \
--cc=penguin-kernel@i-love.sakura.ne.jp \
--cc=rostedt@goodmis.org \
--cc=sergey.senozhatsky@gmail.com \
--cc=syzkaller@googlegroups.com \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).