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Date:   Wed, 24 Jun 2020 07:41:16 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Alexander Popov <alex.popov@linux.com>
Cc:     Luis Chamberlain <mcgrof@kernel.org>, Jann Horn <jannh@google.com>,
        Emese Revfy <re.emese@gmail.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Michal Marek <michal.lkml@markovi.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Thiago Jung Bauermann <bauerman@linux.ibm.com>,
        Jessica Yu <jeyu@kernel.org>,
        Sven Schnelle <svens@stackframe.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
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Subject: Re: [PATCH v2 5/5] gcc-plugins/stackleak: Add 'verbose' plugin
 parameter
Message-ID: <202006240740.5AF6369E53@keescook>
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 <20200624123330.83226-6-alex.popov@linux.com>
 <20200624125305.GG4332@42.do-not-panic.com>
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On Wed, Jun 24, 2020 at 04:09:20PM +0300, Alexander Popov wrote:
> On 24.06.2020 15:53, Luis Chamberlain wrote:
> > On Wed, Jun 24, 2020 at 03:33:30PM +0300, Alexander Popov wrote:
> >> Add 'verbose' plugin parameter for stackleak gcc plugin.
> >> It can be used for printing additional info about the kernel code
> >> instrumentation.
> >>
> >> For using it add the following to scripts/Makefile.gcc-plugins:
> >>   gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STACKLEAK) \
> >>     += -fplugin-arg-stackleak_plugin-verbose
> > 
> > Would be nice if we instead could pass an argument to make which lets
> > us enable this.
> 
> This feature is useful only for debugging stackleak gcc plugin.
> 
> The cflag that enables it is similar to -fplugin-arg-structleak_plugin-verbose,
> which is used for debugging the structleak plugin.
> 
> This debugging feature clutters the kernel build output, I don't think that many
> people will use it. So IMO creating a separate argument for make is not really
> needed.

Yup, agreed. The precedent for plugin verbosity is via CONFIGs. They're
not really general purpose enough to justify a "make" argument.

-- 
Kees Cook