All of lore.kernel.org
 help / color / mirror / Atom feed
From: tip-bot for Masami Hiramatsu <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
	ak@linux.intel.com, ananth@linux.vnet.ibm.com,
	tglx@linutronix.de, gregkh@linux-foundation.org,
	mingo@kernel.org, hpa@zytor.com, dwmw@amazon.co.uk,
	mhiramat@kernel.org, arjan@linux.intel.com
Subject: [tip:x86/pti] retpoline: Introduce start/end markers of indirect thunk
Date: Fri, 19 Jan 2018 07:47:22 -0800	[thread overview]
Message-ID: <tip-736e80a4213e9bbce40a7c050337047128b472ac@git.kernel.org> (raw)
In-Reply-To: <151629206178.10241.6828804696410044771.stgit@devbox>

Commit-ID:  736e80a4213e9bbce40a7c050337047128b472ac
Gitweb:     https://git.kernel.org/tip/736e80a4213e9bbce40a7c050337047128b472ac
Author:     Masami Hiramatsu <mhiramat@kernel.org>
AuthorDate: Fri, 19 Jan 2018 01:14:21 +0900
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 19 Jan 2018 16:31:28 +0100

retpoline: Introduce start/end markers of indirect thunk

Introduce start/end markers of __x86_indirect_thunk_* functions.
To make it easy, consolidate .text.__x86.indirect_thunk.* sections
to one .text.__x86.indirect_thunk section and put it in the
end of kernel text section and adds __indirect_thunk_start/end
so that other subsystem (e.g. kprobes) can identify it.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox

---
 arch/x86/include/asm/nospec-branch.h | 3 +++
 arch/x86/kernel/vmlinux.lds.S        | 6 ++++++
 arch/x86/lib/retpoline.S             | 2 +-
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 7b45d84..19ba5ad 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -194,6 +194,9 @@ enum spectre_v2_mitigation {
 	SPECTRE_V2_IBRS,
 };
 
+extern char __indirect_thunk_start[];
+extern char __indirect_thunk_end[];
+
 /*
  * On VMEXIT we must ensure that no RSB predictions learned in the guest
  * can be followed in the host, by overwriting the RSB completely. Both
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 1e413a93..9b138a0 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -124,6 +124,12 @@ SECTIONS
 		ASSERT(. - _entry_trampoline == PAGE_SIZE, "entry trampoline is too big");
 #endif
 
+#ifdef CONFIG_RETPOLINE
+		__indirect_thunk_start = .;
+		*(.text.__x86.indirect_thunk)
+		__indirect_thunk_end = .;
+#endif
+
 		/* End of text section */
 		_etext = .;
 	} :text = 0x9090
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index cb45c6c..d3415dc 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -9,7 +9,7 @@
 #include <asm/nospec-branch.h>
 
 .macro THUNK reg
-	.section .text.__x86.indirect_thunk.\reg
+	.section .text.__x86.indirect_thunk
 
 ENTRY(__x86_indirect_thunk_\reg)
 	CFI_STARTPROC

  reply	other threads:[~2018-01-19 15:47 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-18 16:13 [PATCH v2 tip/master 0/3] kprobes/x86: retpoline: Fix kprobes for retpoline Masami Hiramatsu
2018-01-18 16:14 ` [PATCH v2 tip/master 1/3] retpoline: Introduce start/end markers of indirect thunk Masami Hiramatsu
2018-01-19 15:47   ` tip-bot for Masami Hiramatsu [this message]
2018-01-18 16:14 ` [PATCH v2 tip/master 2/3] kprobes/x86: Blacklist indirect thunk functions for kprobes Masami Hiramatsu
2018-01-19 15:47   ` [tip:x86/pti] " tip-bot for Masami Hiramatsu
2018-01-18 16:15 ` [PATCH v2 tip/master 3/3] kprobes/x86: Disable optimizing on the function jumps to indirect thunk Masami Hiramatsu
2018-01-19 15:48   ` [tip:x86/pti] " tip-bot for Masami Hiramatsu
2018-01-19  9:03 ` [PATCH v2 tip/master 0/3] kprobes/x86: retpoline: Fix kprobes for retpoline David Woodhouse
2018-01-19  9:03   ` David Woodhouse

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=tip-736e80a4213e9bbce40a7c050337047128b472ac@git.kernel.org \
    --to=tipbot@zytor.com \
    --cc=ak@linux.intel.com \
    --cc=ananth@linux.vnet.ibm.com \
    --cc=arjan@linux.intel.com \
    --cc=dwmw@amazon.co.uk \
    --cc=gregkh@linux-foundation.org \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tip-commits@vger.kernel.org \
    --cc=mhiramat@kernel.org \
    --cc=mingo@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.