diff options
| author | Tom Lendacky <thomas.lendacky@amd.com> | 2018-01-08 16:09:21 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-23 19:50:11 +0100 |
| commit | 20c28c04a6bc2ebd60fa20e5c3a6bf3bfa736d81 (patch) | |
| tree | ea5b37c34938a405f6667f0e3dbb23bdf3aa7bc7 /mm/swap_state.c | |
| parent | e6c591e7a430197777a6456a3cd2db38fffd7647 (diff) | |
x86/cpu/AMD: Make LFENCE a serializing instruction
commit e4d0e84e490790798691aaa0f2e598637f1867ec upstream.
To aid in speculation control, make LFENCE a serializing instruction
since it has less overhead than MFENCE. This is done by setting bit 1
of MSR 0xc0011029 (DE_CFG). Some families that support LFENCE do not
have this MSR. For these families, the LFENCE instruction is already
serializing.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/20180108220921.12580.71694.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Razvan Ghitulete <rga@amazon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/swap_state.c')
0 files changed, 0 insertions, 0 deletions