[MODERATED] [PATCH 1/5] SSB extra v2 1

From: Dave Hansen <dave.hansen@intel.com>
To: speck@linutronix.de
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Subject: [MODERATED] [PATCH 1/5] SSB extra v2 1
Date: Mon,  7 May 2018 16:18:42 -0700	[thread overview]
Message-ID: <=?utf-8?q?=3C8de240e7d1e070bf12e1614443782815d514a6c5=2E152573?= =?utf-8?q?4796=2Egit=2Edave=2Ehansen=40intel=2Ecom=3E?=> (raw)
In-Reply-To: <cover.1525734796.git.dave.hansen@intel.com>
In-Reply-To: <cover.1525734796.git.dave.hansen@intel.com>

From: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 include/linux/nospec.h | 4 ++++
 kernel/bpf/core.c      | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/include/linux/nospec.h b/include/linux/nospec.h
index a908c95..d04ca98 100644
--- a/include/linux/nospec.h
+++ b/include/linux/nospec.h
@@ -63,4 +63,8 @@ int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which);
 int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
 			     unsigned long ctrl);
 
+/* Speculation control for BPF enforced mitigation */
+void arch_bpf_spec_ctrl_disable(void);
+void arch_bpf_spec_ctrl_enable(void);
+
 #endif /* _LINUX_NOSPEC_H */
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index ba03ec3..dd7caa1 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -31,6 +31,7 @@
 #include <linux/rbtree_latch.h>
 #include <linux/kallsyms.h>
 #include <linux/rcupdate.h>
+#include <linux/nospec.h>
 
 #include <asm/unaligned.h>
 
@@ -1805,6 +1806,10 @@ const struct bpf_func_proto bpf_tail_call_proto = {
 	.arg3_type	= ARG_ANYTHING,
 };
 
+/* Stubs for architectures which do not implement BPF speculation control */
+void __weak arch_bpf_spec_ctrl_disable(void) { }
+void __weak arch_bpf_spec_ctrl_enable(void) { }
+
 /* Stub for JITs that only support cBPF. eBPF programs are interpreted.
  * It is encouraged to implement bpf_int_jit_compile() instead, so that
  * eBPF and implicitly also cBPF can get JITed!
-- 
2.9.5
