Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file - Yu-cheng Yu

From: Yu-cheng Yu <yu-cheng.yu@intel.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	 linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	linux-mm@kvack.org,  linux-arch@vger.kernel.org,
	linux-api@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Andy Lutomirski <luto@amacapital.net>,
	Balbir Singh <bsingharora@gmail.com>,
	Borislav Petkov <bp@alien8.de>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Eugene Syromiatnikov <esyr@redhat.com>,
	Florian Weimer <fweimer@redhat.com>,
	"H.J. Lu" <hjl.tools@gmail.com>, Jann Horn <jannh@google.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Kees Cook <keescook@chromium.org>,
	 Mike Kravetz <mike.kravetz@oracle.com>,
	Nadav Amit <nadav.amit@gmail.com>,
	Oleg Nesterov <oleg@redhat.com>,  Pavel Machek <pavel@ucw.cz>,
	Randy Dunlap <rdunlap@infradead.org>,
	"Ravi V. Shankar" <ravi.v.shankar@intel.com>,
	Vedvyas Shanbhogue <vedvyas.shanbhogue@intel.com>,
	 Dave Martin <Dave.Martin@arm.com>
Subject: Re: [PATCH v7 22/27] binfmt_elf: Extract .note.gnu.property from an ELF file
Date: Fri, 07 Jun 2019 09:17:06 -0700	[thread overview]
Message-ID: <1b5778f8f1336ad7a63f4621f189b7f04a56a9ed.camel@intel.com> (raw)
In-Reply-To: <20190607075822.GR3419@hirez.programming.kicks-ass.net>

On Fri, 2019-06-07 at 09:58 +0200, Peter Zijlstra wrote:
> On Thu, Jun 06, 2019 at 01:06:41PM -0700, Yu-cheng Yu wrote:
> > An ELF file's .note.gnu.property indicates features the executable file
> > can support.  For example, the property GNU_PROPERTY_X86_FEATURE_1_AND
> > indicates the file supports GNU_PROPERTY_X86_FEATURE_1_IBT and/or
> > GNU_PROPERTY_X86_FEATURE_1_SHSTK.
> > 
> > With this patch, if an arch needs to setup features from ELF properties,
> > it needs CONFIG_ARCH_USE_GNU_PROPERTY to be set, and a specific
> > arch_setup_property().
> > 
> > For example, for X86_64:
> > 
> > int arch_setup_property(void *ehdr, void *phdr, struct file *f, bool inter)
> > {
> > 	int r;
> > 	uint32_t property;
> > 
> > 	r = get_gnu_property(ehdr, phdr, f, GNU_PROPERTY_X86_FEATURE_1_AND,
> > 			     &property);
> > 	...
> > }
> > 
> > Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> > Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
> 
> Did HJ write this patch as suggested by that SoB chain? If so, you lost
> a From: line on top, if not, the SoB thing is invalid.

I will fix that.

Yu-cheng