summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/sync_core.h
diff options
context:
space:
mode:
authorJens Axboe <axboe@kernel.dk>2018-02-07 15:54:20 -0700
committerJens Axboe <axboe@kernel.dk>2018-02-07 15:54:20 -0700
commit61a695184fcc8f225327206b88320279dd8684af (patch)
tree6cbda2b0e7de94ebad95072d17cc0aa82c9d8ab3 /arch/x86/include/asm/sync_core.h
parent9e05c864993c5442227f83ae1694a737d7a102ed (diff)
parent581e400ff935d34d95811258586128bf11baef15 (diff)
Merge branch 'master' into test
* master: (1190 commits) ASoC: stm32: add of dependency for stm32 drivers ASoC: mt8173-rt5650: fix child-node lookup ASoC: dapm: fix debugfs read using path->connected platform/x86: samsung-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro platform/x86: ideapad-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro platform/x86: dell-laptop: Re-use DEFINE_SHOW_ATTRIBUTE() macro seq_file: Introduce DEFINE_SHOW_ATTRIBUTE() helper macro Documentation/sysctl/user.txt: fix typo MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns MAINTAINERS: update various PALM patterns MAINTAINERS: update "ARM/OXNAS platform support" patterns MAINTAINERS: update Cortina/Gemini patterns MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern MAINTAINERS: remove ANDROID ION pattern mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors mm: docs: fix parameter names mismatch mm: docs: fixup punctuation pipe: read buffer limits atomically pipe: simplify round_pipe_size() pipe: reject F_SETPIPE_SZ with size over UINT_MAX ...
Diffstat (limited to 'arch/x86/include/asm/sync_core.h')
-rw-r--r--arch/x86/include/asm/sync_core.h28
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86/include/asm/sync_core.h b/arch/x86/include/asm/sync_core.h
new file mode 100644
index 000000000000..c67caafd3381
--- /dev/null
+++ b/arch/x86/include/asm/sync_core.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_SYNC_CORE_H
+#define _ASM_X86_SYNC_CORE_H
+
+#include <linux/preempt.h>
+#include <asm/processor.h>
+#include <asm/cpufeature.h>
+
+/*
+ * Ensure that a core serializing instruction is issued before returning
+ * to user-mode. x86 implements return to user-space through sysexit,
+ * sysrel, and sysretq, which are not core serializing.
+ */
+static inline void sync_core_before_usermode(void)
+{
+ /* With PTI, we unconditionally serialize before running user code. */
+ if (static_cpu_has(X86_FEATURE_PTI))
+ return;
+ /*
+ * Return from interrupt and NMI is done through iret, which is core
+ * serializing.
+ */
+ if (in_irq() || in_nmi())
+ return;
+ sync_core();
+}
+
+#endif /* _ASM_X86_SYNC_CORE_H */